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Page 1: Razavi Micro
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RF MICROELECTRONICSSecond Edition

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Prentice Hall PTR’s Communications Engineering and Emerging

Technologies Series provides leading-edge learning and

information about wireless, digital, and other innovative technologies that

are revolutionizing communications around the world. This series reveals

to readers the minds of leading experts in these fields, often as the

technologies are being developed and implemented.

Visit informit.com/communicationengineering for a complete list of available publications.

The Prentice Hall Communications Engineering and

Emerging Technologies Series

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RF MICROELECTRONICSSecond Edition

Behzad Razavi

Upper Saddle River, NJ • Boston • Indianapolis • San FranciscoNew York • Toronto • Montreal • London • Munich • Paris • MadridCapetown • Sydney • Tokyo • Singapore • Mexico City

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Many of the designations used by manufacturers and sellers to distinguish their products areclaimed as trademarks. Where those designations appear in this book, and the publisher wasaware of a trademark claim, the designations have been printed with initial capital letters or inall capitals.

The author and publisher have taken care in the preparation of this book, but make noexpressed or implied warranty of any kind and assume no responsibility for errors oromissions. No liability is assumed for incidental or consequential damages in connection withor arising out of the use of the information or programs contained herein.

The publisher offers excellent discounts on this book when ordered in quantity for bulkpurchases or special sales, which may include electronic versions and/or custom covers andcontent particular to your business, training goals, marketing focus, and branding interests.For more information, please contact:

U.S. Corporate and Government Sales(800) [email protected]

For sales outside the United States, please contact:

International [email protected]

Visit us on the Web: informit.com/ph

Library of Congress Cataloging-in-Publication Data

Razavi, Behzad.RF microelectronics / Behzad Razavi.—2nd ed.

p. cm.Includes bibliographical references and index.ISBN 978-0-13-713473-1 (hardcover : alk. paper) 1. Radio frequency integrated

circuits—Design and construction. I. Title.TK6560.R39 2011621.384’12—dc23

2011026820

Copyright c© 2012 Pearson Education, Inc.

All rights reserved. Printed in the United States of America. This publication is protected bycopyright, and permission must be obtained from the publisher prior to any prohibitedreproduction, storage in a retrieval system, or transmission in any form or by any means,electronic, mechanical, photocopying, recording, or likewise. To obtain permission to usematerial from this work, please submit a written request to Pearson Education, Inc.,Permissions Department, One Lake Street, Upper Saddle River, New Jersey 07458, or youmay fax your request to (201) 236-3290.

ISBN-13: 978-0-13-713473-1ISBN-10: 0-13-713473-8

Text printed in the United States at Hamilton Printing Company in Castleton, New York.First printing, September 2011

PublisherPaul Boger

Acquisitions EditorBernard Goodwin

Managing EditorJohn Fuller

Full-Service ProductionManagerJulie B. Nahil

Copy EditorGeneil Breeze

IndexerTed Laux

ProofreaderLinda Seifert

Publishing CoordinatorMichelle Housley

Cover DesignerGary Adair

CompositorLaurelTech

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To the memory of my parents

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CONTENTS

PREFACE TO THE SECOND EDITION xvPREFACE TO THE FIRST EDITION xixACKNOWLEDGMENTS xxiABOUT THE AUTHOR xxiii

CHAPTER 1 INTRODUCTION TO RF AND WIRELESSTECHNOLOGY 1

1.1 A Wireless World 11.2 RF Design Is Challenging 31.3 The Big Picture 4References 5

CHAPTER 2 BASIC CONCEPTS IN RF DESIGN 72.1 General Considerations 7

2.1.1 Units in RF Design 72.1.2 Time Variance 92.1.3 Nonlinearity 12

2.2 Effects of Nonlinearity 142.2.1 Harmonic Distortion 142.2.2 Gain Compression 162.2.3 Cross Modulation 202.2.4 Intermodulation 212.2.5 Cascaded Nonlinear Stages 292.2.6 AM/PM Conversion 33

2.3 Noise 352.3.1 Noise as a Random Process 362.3.2 Noise Spectrum 37

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2.3.3 Effect of Transfer Function on Noise 392.3.4 Device Noise 402.3.5 Representation of Noise in Circuits 46

2.4 Sensitivity and Dynamic Range 582.4.1 Sensitivity 592.4.2 Dynamic Range 60

2.5 Passive Impedance Transformation 622.5.1 Quality Factor 632.5.2 Series-to-Parallel Conversion 632.5.3 Basic Matching Networks 652.5.4 Loss in Matching Networks 69

2.6 Scattering Parameters 712.7 Analysis of Nonlinear Dynamic Systems 75

2.7.1 Basic Considerations 752.8 Volterra Series 77

2.8.1 Method of Nonlinear Currents 81References 86Problems 86

CHAPTER 3 COMMUNICATION CONCEPTS 913.1 General Considerations 913.2 Analog Modulation 93

3.2.1 Amplitude Modulation 933.2.2 Phase and Frequency Modulation 95

3.3 Digital Modulation 993.3.1 Intersymbol Interference 1013.3.2 Signal Constellations 1053.3.3 Quadrature Modulation 1073.3.4 GMSK and GFSK Modulation 1123.3.5 Quadrature Amplitude Modulation 1143.3.6 Orthogonal Frequency Division Multiplexing 115

3.4 Spectral Regrowth 1183.5 Mobile RF Communications 1193.6 Multiple Access Techniques 123

3.6.1 Time and Frequency Division Duplexing 1233.6.2 Frequency-Division Multiple Access 1253.6.3 Time-Division Multiple Access 1253.6.4 Code-Division Multiple Access 126

3.7 Wireless Standards 1303.7.1 GSM 1323.7.2 IS-95 CDMA 1373.7.3 Wideband CDMA 1393.7.4 Bluetooth 1433.7.5 IEEE802.11a/b/g 147

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3.8 Appendix I: Differential Phase Shift Keying 151References 152Problems 152

CHAPTER 4 TRANSCEIVER ARCHITECTURES 1554.1 General Considerations 1554.2 Receiver Architectures 160

4.2.1 Basic Heterodyne Receivers 1604.2.2 Modern Heterodyne Receivers 1714.2.3 Direct-Conversion Receivers 1794.2.4 Image-Reject Receivers 2004.2.5 Low-IF Receivers 214

4.3 Transmitter Architectures 2264.3.1 General Considerations 2264.3.2 Direct-Conversion Transmitters 2274.3.3 Modern Direct-Conversion Transmitters 2384.3.4 Heterodyne Transmitters 2444.3.5 Other TX Architectures 248

4.4 OOK Transceivers 248References 249Problems 250

CHAPTER 5 LOW-NOISE AMPLIFIERS 2555.1 General Considerations 2555.2 Problem of Input Matching 2635.3 LNA Topologies 266

5.3.1 Common-Source Stage with Inductive Load 2665.3.2 Common-Source Stage with Resistive Feedback 2695.3.3 Common-Gate Stage 2725.3.4 Cascode CS Stage with Inductive Degeneration 2845.3.5 Variants of Common-Gate LNA 2965.3.6 Noise-Cancelling LNAs 3005.3.7 Reactance-Cancelling LNAs 303

5.4 Gain Switching 3055.5 Band Switching 3125.6 High-IP2 LNAs 313

5.6.1 Differential LNAs 3145.6.2 Other Methods of IP2 Improvement 323

5.7 Nonlinearity Calculations 3255.7.1 Degenerated CS Stage 3255.7.2 Undegenerated CS Stage 3295.7.3 Differential and Quasi-Differential Pairs 3315.7.4 Degenerated Differential Pair 332

References 333Problems 333

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CHAPTER 6 MIXERS 3376.1 General Considerations 337

6.1.1 Performance Parameters 3386.1.2 Mixer Noise Figures 3436.1.3 Single-Balanced and Double-Balanced Mixers 348

6.2 Passive Downconversion Mixers 3506.2.1 Gain 3506.2.2 LO Self-Mixing 3576.2.3 Noise 3576.2.4 Input Impedance 3646.2.5 Current-Driven Passive Mixers 366

6.3 Active Downconversion Mixers 3686.3.1 Conversion Gain 3706.3.2 Noise in Active Mixers 3776.3.3 Linearity 387

6.4 Improved Mixer Topologies 3936.4.1 Active Mixers with Current-Source Helpers 3936.4.2 Active Mixers with Enhanced Transconductance 3946.4.3 Active Mixers with High IP2 3976.4.4 Active Mixers with Low Flicker Noise 405

6.5 Upconversion Mixers 4086.5.1 Performance Requirements 4086.5.2 Upconversion Mixer Topologies 409

References 424Problems 425

CHAPTER 7 PASSIVE DEVICES 4297.1 General Considerations 4297.2 Inductors 431

7.2.1 Basic Structure 4317.2.2 Inductor Geometries 4357.2.3 Inductance Equations 4367.2.4 Parasitic Capacitances 4397.2.5 Loss Mechanisms 4447.2.6 Inductor Modeling 4557.2.7 Alternative Inductor Structures 460

7.3 Transformers 4707.3.1 Transformer Structures 4707.3.2 Effect of Coupling Capacitance 4757.3.3 Transformer Modeling 475

7.4 Transmission Lines 4767.4.1 T-Line Structures 478

7.5 Varactors 4837.6 Constant Capacitors 490

7.6.1 MOS Capacitors 4917.6.2 Metal-Plate Capacitors 493

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References 495Problems 496

CHAPTER 8 OSCILLATORS 4978.1 Performance Parameters 4978.2 Basic Principles 501

8.2.1 Feedback View of Oscillators 5028.2.2 One-Port View of Oscillators 508

8.3 Cross-Coupled Oscillator 5118.4 Three-Point Oscillators 5178.5 Voltage-Controlled Oscillators 518

8.5.1 Tuning Range Limitations 5218.5.2 Effect of Varactor Q 522

8.6 LC VCOs with Wide Tuning Range 5248.6.1 VCOs with Continuous Tuning 5248.6.2 Amplitude Variation with Frequency Tuning 5328.6.3 Discrete Tuning 532

8.7 Phase Noise 5368.7.1 Basic Concepts 5368.7.2 Effect of Phase Noise 5398.7.3 Analysis of Phase Noise: Approach I 5448.7.4 Analysis of Phase Noise: Approach II 5578.7.5 Noise of Bias Current Source 5658.7.6 Figures of Merit of VCOs 570

8.8 Design Procedure 5718.8.1 Low-Noise VCOs 573

8.9 LO Interface 5758.10 Mathematical Model of VCOs 5778.11 Quadrature Oscillators 581

8.11.1 Basic Concepts 5818.11.2 Properties of Coupled Oscillators 5848.11.3 Improved Quadrature Oscillators 589

8.12 Appendix I: Simulation of Quadrature Oscillators 592References 593Problems 594

CHAPTER 9 PHASE-LOCKED LOOPS 5979.1 Basic Concepts 597

9.1.1 Phase Detector 5979.2 Type-I PLLs 600

9.2.1 Alignment of a VCO’s Phase 6009.2.2 Simple PLL 6019.2.3 Analysis of Simple PLL 6039.2.4 Loop Dynamics 6069.2.5 Frequency Multiplication 6099.2.6 Drawbacks of Simple PLL 611

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9.3 Type-II PLLs 6119.3.1 Phase/Frequency Detectors 6129.3.2 Charge Pumps 6149.3.3 Charge-Pump PLLs 6159.3.4 Transient Response 6209.3.5 Limitations of Continuous-Time Approximation 6229.3.6 Frequency-Multiplying CPPLL 6239.3.7 Higher-Order Loops 625

9.4 PFD/CP Nonidealities 6279.4.1 Up and Down Skew and Width Mismatch 6279.4.2 Voltage Compliance 6309.4.3 Charge Injection and Clock Feedthrough 6309.4.4 Random Mismatch between Up and Down Currents 6329.4.5 Channel-Length Modulation 6339.4.6 Circuit Techniques 634

9.5 Phase Noise in PLLs 6389.5.1 VCO Phase Noise 6389.5.2 Reference Phase Noise 643

9.6 Loop Bandwidth 6459.7 Design Procedure 6469.8 Appendix I: Phase Margin of Type-II PLLs 647References 651Problems 652

CHAPTER 10 INTEGER-N FREQUENCY SYNTHESIZERS 65510.1 General Considerations 65510.2 Basic Integer-N Synthesizer 65910.3 Settling Behavior 66110.4 Spur Reduction Techniques 66410.5 PLL-Based Modulation 667

10.5.1 In-Loop Modulation 66710.5.2 Modulation by Offset PLLs 670

10.6 Divider Design 67310.6.1 Pulse Swallow Divider 67410.6.2 Dual-Modulus Dividers 67710.6.3 Choice of Prescaler Modulus 68210.6.4 Divider Logic Styles 68310.6.5 Miller Divider 69910.6.6 Injection-Locked Dividers 70710.6.7 Divider Delay and Phase Noise 709

References 712Problems 713

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CHAPTER 11 FRACTIONAL-N SYNTHESIZERS 71511.1 Basic Concepts 71511.2 Randomization and Noise Shaping 718

11.2.1 Modulus Randomization 71811.2.2 Basic Noise Shaping 72211.2.3 Higher-Order Noise Shaping 72811.2.4 Problem of Out-of-Band Noise 73211.2.5 Effect of Charge Pump Mismatch 733

11.3 Quantization Noise Reduction Techniques 73811.3.1 DAC Feedforward 73811.3.2 Fractional Divider 74211.3.3 Reference Doubling 74311.3.4 Multiphase Frequency Division 745

11.4 Appendix I: Spectrum of Quantization Noise 748References 749Problems 749

CHAPTER 12 POWER AMPLIFIERS 75112.1 General Considerations 751

12.1.1 Effect of High Currents 75412.1.2 Efficiency 75512.1.3 Linearity 75612.1.4 Single-Ended and Differential PAs 758

12.2 Classification of Power Amplifiers 76012.2.1 Class A Power Amplifiers 76012.2.2 Class B Power Amplifiers 76412.2.3 Class C Power Amplifiers 768

12.3 High-Efficiency Power Amplifiers 77012.3.1 Class A Stage with Harmonic Enhancement 77112.3.2 Class E Stage 77212.3.3 Class F Power Amplifiers 775

12.4 Cascode Output Stages 77612.5 Large-Signal Impedance Matching 78012.6 Basic Linearization Techniques 782

12.6.1 Feedforward 78312.6.2 Cartesian Feedback 78612.6.3 Predistortion 78712.6.4 Envelope Feedback 788

12.7 Polar Modulation 79012.7.1 Basic Idea 79012.7.2 Polar Modulation Issues 79312.7.3 Improved Polar Modulation 796

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12.8 Outphasing 80212.8.1 Basic Idea 80212.8.2 Outphasing Issues 805

12.9 Doherty Power Amplifier 81112.10 Design Examples 814

12.10.1 Cascode PA Examples 81512.10.2 Positive-Feedback PAs 81912.10.3 PAs with Power Combining 82112.10.4 Polar Modulation PAs 82412.10.5 Outphasing PA Example 826

References 830Problems 831

CHAPTER 13 TRANSCEIVER DESIGN EXAMPLE 83313.1 System-Level Considerations 833

13.1.1 Receiver 83413.1.2 Transmitter 83813.1.3 Frequency Synthesizer 84013.1.4 Frequency Planning 844

13.2 Receiver Design 84813.2.1 LNA Design 84913.2.2 Mixer Design 85113.2.3 AGC 856

13.3 TX Design 86113.3.1 PA Design 86113.3.2 Upconverter 867

13.4 Synthesizer Design 86913.4.1 VCO Design 86913.4.2 Divider Design 87813.4.3 Loop Design 882

References 886Problems 886

INDEX 889

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PREFACE TO THE SECOND EDITION

In the 14 years since the first edition of this book, RF IC design has experienced a dramaticmetamorphosis. Innovations in transceiver architectures, circuit topologies, and devicestructures have led to highly-integrated “radios” that span a broad spectrum of applica-tions. Moreover, new analytical and modeling techniques have considerably improvedour understanding of RF circuits and their underlying principles. A new edition wastherefore due.

The second edition differs from the first in several respects:

1. I realized at the outset—three-and-a-half years ago—that simply adding “patches”to the first edition would not reflect today’s RF microelectronics. I thus closed thefirst edition and began with a clean slate. The two editions have about 10% overlap.

2. I wanted the second edition to contain greater pedagogy, helping the reader under-stand both the fundamentals and the subtleties. I have thus incorporated hundredsof examples and problems.

3. I also wanted to teach design in addition to analysis. I have thus included step-by-step design procedures and examples. Furthermore, I have dedicated Chapter 13 tothe step-by-step transistor-level design of a dual-band WiFi transceiver.

4. With the tremendous advances in RF design, some of the chapters have inevitablybecome longer and some have been split into two or more chapters. As a result, thesecond edition is nearly three times as long as the first.

Suggestions for Instructors and Students

The material in this book is much more than can be covered in one quarter or semester.The following is a possible sequence of the chapters that can be taught in one term withreasonable depth. Depending on the students’ background and the instructor’s preference,other combinations of topics can also be covered in one quarter or semester.

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xvi Preface to the Second Edition

Chapter 1: Introduction to RF and Wireless TechnologyThis chapter provides the big picture and should be covered in about half an hour.

Chapter 2: Basic Concepts in RF DesignThe following sections should be covered: General Considerations, Effects of

Nonlinearity (the section on AM/PM Conversion can be skipped), Noise, and Sen-sitivity and Dynamic Range. (The sections on Passive Impedance Transformation,Scattering Parameters, and Analysis of Nonlinear Dynamic Systems can be skipped.)This chapter takes about six hours of lecture.

Chapter 3: Communication ConceptsThis chapter can be covered minimally in a quarter system—for example, Analog

Modulation, Quadrature Modulation, GMSK Modulation, Multiple Access Tech-niques, and the IEEE802.11a/b/g Standard. In a semester system, the concept of signalconstellations can be introduced and a few more modulation schemes and wirelessstandards can be taught. This chapter takes about two hours in a quarter system andthree hours in a semester system.

Chapter 4: Transceiver ArchitecturesThis chapter is relatively long and should be taught selectively. The following

sections should be covered: General Considerations, Basic and Modern Hetero-dyne Receivers, Direct-Conversion Receivers, Image-Reject Receivers, and Direct-Conversion Transmitters. In a semester system, Low-IF Receivers and HeterodyneTransmitters can be covered as well. This chapter takes about eight hours in a quartersystem and ten hours in a semester system.

Chapter 5: Low-Noise AmplifiersThe following sections should be covered: General Considerations, Problem of

Input Matching, and LNA Topologies. A semester system can also include GainSwitching and Band Switching or High-IP2 LNAs. This chapter takes about six hoursin a quarter system and eight hours in a semester system.

Chapter 6: MixersThe following sections should be covered: General Considerations, Passive

Downconversion Mixers (the computation of noise and input impedance of voltage-driven sampling mixers can be skipped), Active Downconversion Mixers, andActive Mixers with High IP2. In a semester system, Active Mixers with EnhancedTransconductance, Active Mixers with Low Flicker Noise, and UpconversionMixers can also be covered. This chapter takes about eight hours in a quarter systemand ten hours in a semester system.

Chapter 7: Passive DevicesThis chapter may not fit in a quarter system. In a semester system, about three

hours can be spent on basic inductor structures and loss mechanisms and MOSvaractors.

Chapter 8: OscillatorsThis is a long chapter and should be taught selectively. The following sections

should be covered: Basic Principles, Cross-Coupled Oscillator, Voltage-Controlled

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Preface to the Second Edition xvii

Oscillators, Low-Noise VCOs. In a quarter system, there is little time to cover phasenoise. In a semester system, both approaches to phase noise analysis can be taught.This chapter takes about six hours in a quarter system and eight hours in a semestersystem.

Chapter 9: Phase-Locked LoopsThis chapter forms the foundation for synthesizers. In fact, if taught carefully, this

chapter naturally teaches integer-N synthesizers, allowing a quarter system to skip thenext chapter. The following sections should be covered: Basic Concepts, Type-I PLLs,Type-II PLLs, and PFD/CP Nonidealities. A semester system can also include PhaseNoise in PLLs and Design Procedure. This chapter takes about four hours in a quartersystem and six hours in a semester system.

Chapter 10: Integer-N SynthesizersThis chapter is likely sacrificed in a quarter system. A semester system can spend

about four hours on Spur Reduction Techniques and Divider Design.

Chapter 11: Fractional-N SynthesizersThis chapter is likely sacrificed in a quarter system. A semester system can spend

about four hours on Randomization and Noise Shaping. The remaining sections maybe skipped.

Chapter 12: Power AmplifiersThis is a long chapter and, unfortunately, is often sacrificed for other chapters.

If coverage is desired, the following sections may be taught: General Considera-tions, Classification of Power Amplifiers, High-Efficiency Power Amplifiers, CascodeOutput Stages, and Basic Linearization Techniques. These topics take about fourhours of lecture. Another four hours can be spent on Doherty Power Amplifier, PolarModulation, and Outphasing.

Chapter 13: Transceiver Design ExampleThis chapter provides a step-by-step design of a dual-band transceiver. It is possi-

ble to skip the state-of-the-art examples in Chapters 5, 6, and 8 to allow some time forthis chapter. The system-level derivations may still need to be skipped. The RX, TX,and synthesizer transistor-level designs can be covered in about four hours.

A solutions manual is available for instructors via the Pearson Higher Education Instruc-tor Resource Center web site: pearsonhighered.com/irc; and a set of Powerpoint slides isavailable for instructors at informit.com/razavi. Additional problems will be posted on thebook’s website (informit.com/razavi).

—Behzad RazaviJuly 2011

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PREFACE TO THE FIRST EDITION

The annual worldwide sales of cellular phones has exceeded $2.5B. With 4.5 million cus-tomers, home satellite networks comprise a $2.5B industry. The global positioning systemis expected to become a $5B market by the year 2000. In Europe, the sales of equip-ment and services for mobile communications will reach $30B by 1998. The statistics areoverwhelming.

The radio frequency (RF) and wireless market has suddenly expanded to unimaginabledimensions. Devices such as pagers, cellular and cordless phones, cable modems, andRF identification tags are rapidly penetrating all aspects of our lives, evolving from luxuryitems to indispensable tools. Semiconductor and system companies, small and large, analogand digital, have seen the statistics and are striving to capture their own market share byintroducing various RF products.

RF design is unique in that it draws upon many disciplines unrelated to integratedcircuits (ICs). The RF knowledge base has grown for almost a century, creating a seeminglyendless body of literature for the novice.

This book deals with the analysis and design of RF integrated circuits and systems.Providing a systematic treatment of RF electronics in a tutorial language, the book beginswith the necessary background knowledge from microwave and communication theoryand leads the reader to the design of RF transceivers and circuits. The text emphasizes botharchitecture and circuit level issues with respect to monolithic implementation in VLSItechnologies. The primary focus is on bipolar and CMOS design, but most of the con-cepts can be applied to other technologies as well. The reader is assumed to have a basicunderstanding of analog IC design and the theory of signals and systems.

The book consists of nine chapters. Chapter 1 gives a general introduction, posing ques-tions and providing motivation for subsequent chapters. Chapter 2 describes basic conceptsin RF and microwave design, emphasizing the effects of nonlinearity and noise.

Chapters 3 and 4 take the reader to the communication system level, giving an overviewof modulation, detection, multiple access techniques, and wireless standards. While ini-tially appearing to be unnecessary, this material is in fact essential to the concurrent designof RF circuits and systems.

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xx Preface to the First Edition

Chapter 5 deals with transceiver architectures, presenting various receiver and trans-mitter topologies along with their merits and drawbacks. This chapter also includes anumber of case studies that exemplify the approaches taken in actual RF products.

Chapters 6 through 9 address the design of RF building blocks: low-noise amplifiersand mixers, oscillators, frequency synthesizers, and power amplifiers, with particular atten-tion to minimizing the number of off-chip components. An important goal of these chaptersis to demonstrate how the system requirements define the parameters of the circuits and howthe performance of each circuit impacts that of the overall transceiver.

I have taught approximately 80% of the material in this book in a 4-unit graduate courseat UCLA. Chapters 3, 4, 8, and 9 had to be shortened in a ten-week quarter, but in a semestersystem they can be covered more thoroughly.

Much of my RF design knowledge comes from interactions with colleagues. HelenKim, Ting-Ping Liu, and Dan Avidor of Bell Laboratories, and David Su and AndrewGzegorek of Hewlett-Packard Laboratories have contributed to the material in this book inmany ways. The text was also reviewed by a number of experts: Stefan Heinen (Siemens),Bart Jansen (Hewlett-Packard), Ting-Ping Liu (Bell Labs), John Long (University ofToronto), Tadao Nakagawa (NTT), Gitty Nasserbakht (Texas Instruments), Ted Rappaport(Virginia Tech), Tirdad Sowlati (Gennum), Trudy Stetzler (Bell Labs), David Su (Hewlett-Packard), and Rick Wesel (UCLA). In addition, a number of UCLA students, includingFarbod Behbahani, Hooman Darabi, John Leete, and Jacob Rael, “test drove” variouschapters and provided useful feedback. I am indebted to all of the above for their kindassistance.

I would also like to thank the staff at Prentice Hall, particularly Russ Hall, MaureenDiana, and Kerry Riordan for their support.

—Behzad RazaviJuly 1997

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ACKNOWLEDGMENTS

I have been fortunate to benefit from the support of numerous people during the writing,review, and production phases of this book. I would like to express my thanks here.

Even after several rounds of self-editing, it is possible that typos or subtle mistakeshave eluded the author. Sometimes, an explanation that is clear to the author may not beso to the reader. And, occasionally, the author may have missed a point or a recent devel-opment. A detailed review of the book by others thus becomes necessary. The followingindividuals meticulously reviewed various chapters, discovered my mistakes, and madevaluable suggestions:

Ali Afsahi (Broadcom)Pietro Andreani (Lund University)Ashkan Borna (UC Berkeley)Jonathan Borremans (IMEC)Debopriyo Chowdhury (UC Berkeley)Matteo Conta (Consultant)Ali Homayoun (UCLA)Velntina del Lattorre (Consultant)Jane Gu (University of Florida)Peng Han (Beken)Pavan Hanumolu (Oregon State University)Daquan Huang (Texas Instruments)Sy-Chyuan Hwu (UCLA)Amin Jahanian (UCI)Jithin Janardhan (UCLA)Shinwon Kang (UC Berkeley)Iman Khajenasiri

(Sharif University of Technology)Yanghyo Kim (UCLA)

Abbas Komijani (Atheros)Tai-Cheng Lee (National Taiwan University)Antonio Liscidini (University of Pavia)Shen-Iuan Liu (National Taiwan University)Xiaodong Liu (Lund University)Jian Hua Lu (UCLA)Howard Luong (Hong Kong University ofScience and Technology)Elvis Mak (University of Macau)Rabih Makarem (Atheros)Rui Martins (University of Macau)Andrea Mazzanti (University of Pavia)Karthik Natarajan

(University of Washington)Nitin Nidhi (UCLA)Joung Park (UCLA)Paul Park (Atheros)Stefano Pellerano (Intel)Jafar Savoj (Xilinx)

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xxii Acknowledgments

Parmoon Seddighrad(University of Washington)

Alireza Shirvani (Ralink)Tirdad Sowlati (Qualcomm)Francesco Svelto (University of Pavia)Enrico Temporiti (ST Microelectronics)Federico Vecchi (University of Pavia)Vijay Viswam (Lund University)

Vidojkovic Vojkan (IMEC)Ning Wang (UCLA)Weifeng Wang (Beken)Zhi Gong Wang (Southeast University)Marco Zanuso (UCLA)Yunfeng Zhao (Beken)Alireza Zolfaghari (Broadcom)

I am thankful for their enthusiastic, organized, and to-the-point reviews.The book’s production was proficiently managed by the staff at Prentice Hall, including

Bernard Goodwin and Julie Nahil. I would like to thank both.As with my other books, my wife, Angelina, typed the entire second edition in Latex

and selflessly helped me in this three-and-a-half-year endeavor. I am grateful to her.

—Behzad Razavi

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ABOUT THE AUTHOR

Behzad Razavi received the BSEE degree from Sharif University of Technology in 1985and MSEE and PhDEE degrees from Stanford University in 1988 and 1992, respectively.He was with AT&T Bell Laboratories and Hewlett-Packard Laboratories until 1996. Since1996, he has been associate professor and, subsequently, professor of electrical engi-neering at University of California, Los Angeles. His current research includes wirelesstransceivers, frequency synthesizers, phase-locking and clock recovery for high-speed datacommunications, and data converters.

Professor Razavi was an adjunct professor at Princeton University from 1992 to 1994,and at Stanford University in 1995. He served on the Technical Program Committees of theInternational Solid-State Circuits Conference (ISSCC) from 1993 to 2002 and VLSI Cir-cuits Symposium from 1998 to 2002. He has also served as guest editor and associate editorof the IEEE Journal of Solid-State Circuits, IEEE Transactions on Circuits and Systems,and International Journal of High Speed Electronics.

Professor Razavi received the Beatrice Winner Award for Editorial Excellence at the1994 ISSCC; the best paper award at the 1994 European Solid-State Circuits Conference;the best panel award at the 1995 and 1997 ISSCC; the TRW Innovative Teaching Award in1997; the best paper award at the IEEE Custom Integrated Circuits Conference (CICC) in1998; and McGraw-Hill First Edition of the Year Award in 2001. He was the co-recipientof both the Jack Kilby Outstanding Student Paper Award and the Beatrice Winner Awardfor Editorial Excellence at the 2001 ISSCC. He received the Lockheed Martin Excellencein Teaching Award in 2006; the UCLA Faculty Senate Teaching Award in 2007; and theCICC Best Invited Paper Award in 2009. He was also recognized as one of the top tenauthors in the fifty-year history of ISSCC. He received the IEEE Donald Pederson Awardin Solid-State Circuits in 2012.

Professor Razavi is an IEEE Distinguished Lecturer, a Fellow of IEEE, and theauthor of Principles of Data Conversion System Design, RF Microelectronics, First Edi-tion (translated to Chinese, Japanese, and Korean), Design of Analog CMOS IntegratedCircuits (translated to Chinese, Japanese, and Korean), Design of Integrated Circuits for

xxiii

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xxiv About the Author

Optical Communications, and Fundamentals of Microelectronics (translated to Korean andPortuguese), and the editor of Monolithic Phase-Locked Loops and Clock Recovery Circuitsand Phase-Locking in High-Performance Systems.

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CHAPTER

1INTRODUCTION TO RF AND

WIRELESS TECHNOLOGY

Compare two RF transceivers designed for cell phones:

“A 2.7-V GSM RF Transceiver IC” [1] (published in 1997)

“A Single-Chip 10-Band WCDMA/HSDPA 4-Band GSM/EDGE SAW-Less CMOS Receiver with DigRF 3G Interface and 190-dBm IIP2” [2](published in 2009)

Why is the latter much more complex than the former? Does the latter have a higher perfor-mance or only greater functionality? Which one costs more? Which one consumes a higherpower? What do all the acronyms GSM, WCDMA, HSDPA, EDGE, SAW, and IIP2 mean?Why do we care?

The field of RF communication has grown rapidly over the past two decades, reachingfar into our lives and livelihood. Our cell phones serve as an encyclopedia, a shoppingterminus, a GPS guide, a weather monitor, and a telephone—all thanks to their wirelesscommunication devices. We can now measure a patient’s brain or heart activity and transmitthe results wirelessly, allowing the patient to move around untethered. We use RF devicesto track merchandise, pets, cattle, children, and convicts.

1.1 A WIRELESS WORLD

Wireless communication has become almost as ubiquitous as electricity; our refrigera-tors and ovens may not have a wireless device at this time, but it is envisioned that ourhomes will eventually incorporate a wireless network that controls every device and appli-ance. High-speed wireless links will allow seamless connections among our laptops, digitalcameras, camcorders, cell phones, printers, TVs, microwave ovens, etc. Today’s WiFi andBluetooth connections are simple examples of such links.

How did wireless communication take over the world? A confluence of factors hascontributed to this explosive growth. The principal reason for the popularity of wireless

1

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2 Chap. 1. Introduction to RF and Wireless Technology

communication is the ever-decreasing cost of electronics. Today’s cell phones cost aboutthe same as those a decade ago but they offer many more functions and features: manyfrequency bands and communication modes, WiFi, Bluetooth, GPS, computing, storage,a digital camera, and a user-friendly interface. This affordability finds its roots in inte-gration, i.e., how much functionality can be placed on a single chip—or, rather, how fewcomponents are left off-chip. The integration, in turn, owes its steady rise to (1) the scalingof VLSI processes, particularly, CMOS technology, and (2) innovations in RF architectures,circuits, and devices.

Along with higher integration levels, the performance of RF circuits has also improved.For example, the power consumption necessary for a given function has decreased and thespeed of RF circuits has increased. Figure 1.1 illustrates some of the trends in RF integratedcircuits (ICs) and technology for the past two decades. The minimum feature size of CMOS

1000

100

10

188 90 92 94 96 98 00 02 04 06 08 10

Year

TO

scill

atio

n F

req

uen

cy a

nd

f

(GH

z)

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um

0.35

um

0.25

um

0.18

um

0.13

um 90 n

m

Osc. Freq.

f T

40 n

m

65 n

m

[3] [4][5]

[6]

[7]

[8] [9][10]

88 90 92 94 96 98 00 02 04 06 08 10Year

10

20

30

40

50

60

70

Nu

mb

er o

f R

F a

nd

Wir

eles

s P

aper

s at

ISS

CC

Figure 1.1 Trends in RF circuits and technology.

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Sec. 1.2. RF Design Is Challenging 3

technology has fallen from 0.5 μm to 40 nm, the transit frequency,1 fT , of NMOS deviceshas risen from about 12 GHz to several hundred gigahertz, and the speed of RF oscillatorshas gone from 1.2 GHz to 300 GHz. Also shown is the number of RF and wireless designpapers presented at the International Solid-State Circuits Conference (ISSCC) each year,revealing the fast-growing activity in this field.

1.2 RF DESIGN IS CHALLENGING

Despite many decades of work on RF and microwave theory and two decades of researchon RF ICs, the design and implementation of RF circuits and transceivers remain chal-lenging. This is for three reasons. First, as shown in Fig. 1.2, RF design draws upon amultitude of disciplines, requiring a good understanding of fields that are seemingly irrel-evant to integrated circuits. Most of these fields have been under study for more than halfa century, presenting a massive body of knowledge to a person entering RF IC design.One objective of this book is to provide the necessary background from these disciplineswithout overwhelming the reader.

Second, RF circuits and transceivers must deal with numerous trade-offs, summarizedin the “RF design hexagon” of Fig. 1.3. For example, to lower the noise of a front-endamplifier, we must consume a greater power or sacrifice linearity. We will encounter thesetrade-offs throughout this book.

Third, the demand for higher performance, lower cost, and greater functionality con-tinues to present new challenges. The early RF IC design work in the 1990s strove tointegrate one transceiver—perhaps along with the digital baseband processor—on a singlechip. Today’s efforts, on the other hand, aim to accommodate multiple transceivers oper-ating in different frequency bands for different wireless standards (e.g., Bluetooth, WiFi,GPS, etc.). The two papers mentioned at the beginning of this chapter exemplify this trend.It is interesting to note that the silicon chip area of early single-transceiver systems was

RF Design

CommunicationTheory

RandomSignals

TransceiverArchitectures

IC Design

WirelessStandards

MultipleAccess

MicrowaveTheory

SignalPropagation

CADTools

Figure 1.2 Various disciplines necessary in RF design.

1. The transit frequency is defined as the frequency at which the small-signal current gain of a device falls tounity.

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4 Chap. 1. Introduction to RF and Wireless Technology

Noise Power

Linearity

GainSupplyVoltage

Frequency

Figure 1.3 RF design hexagon.

dominated by the digital baseband processor, allowing RF and analog designers some lat-itude in the choice of their circuit and device topologies. In today’s designs, however, themultiple transceivers tend to occupy a larger area than the baseband processor, requiringthat RF and analog sections be designed with much care about their area consumption.For example, while on-chip spiral inductors (which have a large footprint) were utilized inabundance in older systems, they are now used only sparingly.

1.3 THE BIG PICTURE

The objective of an RF transceiver is to transmit and receive information. We envisionthat the transmitter (TX) somehow processes the voice or data signal and applies the resultto the antenna [Fig. 1.4(a)]. Similarly, the receiver (RX) senses the signal picked up bythe antenna and processes it so as to reconstruct the original voice or data information.Each black box in Fig. 1.4(a) contains a great many functions, but we can readily maketwo observations: (1) the TX must drive the antenna with a high power level so that thetransmitted signal is strong enough to reach far distances, and (2) the RX may sense asmall signal (e.g., when a cell phone is used in the basement of a building) and must firstamplify the signal with low noise. We now architect our transceiver as shown in Fig. 1.4(b),where the signal to be transmitted is first applied to a “modulator” or “upconverter” so thatits center frequency goes from zero to, say, fc 5 2.4 GHz. The result drives the antennathrough a “power amplifier” (PA). On the receiver side, the signal is sensed by a “low-noise amplifier” (LNA) and subsequently by a “downconverter” or “demodulator” (alsoknown as a “detector”).

The upconversion and downconversion paths in Fig. 1.4(b) are driven by an oscillator,which itself is controlled by a “frequency synthesizer.” Figure 1.4(c) shows the overalltransceiver.2 The system looks deceptively simple, but we will need the next 900 pages tocover its RF sections. And perhaps another 900 pages to cover the analog-to-digital anddigital-to-analog converters.

2. In some cases, the modulator and the upconverter are one and the same. In some other cases, the modula-tion is performed in the digital domain before upconversion. Most receivers demodulate and detect the signaldigitally, requiring only a downconverter in the analog domain.

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References 5

?

Transmitter (TX) Receiver (RX)

?Voice or

DataReconstructedVoice or Data

PowerAmplifier

Upconverter orModulator

Voice orData

0 f

AmplifierLow−Noise

ff c

Downconverter orDemodulator

ReconstructedVoice or Data

ff c 0 f

Downconverter orDemodulator

LNA

PA

Upconverter orModulator

FrequencySynthesizer

Oscillator

ConverterAnalog−to−Digital

ConverterDigital−to−Analog

Dig

ital

Bas

eban

d P

roce

sso

r

(a)

(b)

(c)

Figure 1.4 (a) Simple view of RF communication, (b) more complete view, (c) generic RFtransceiver.

REFERENCES

[1] T. Yamawaki et al., “A 2.7-V GSM RF Transceiver IC,” IEEE J. Solid-State Circuits, vol. 32,pp. 2089–2096, Dec. 1997.

[2] D. Kaczman et al., “A Single-Chip 10-Band WCDMA/HSDPA 4-Band GSM/EDGE SAW-less CMOS Receiver with DigRF 3G Interface and 190-dBm IIP2,” IEEE J. Solid-StateCircuits, vol. 44, pp. 718–739, March 2009.

[3] M. Banu, “MOS Oscillators with Multi-Decade Tuning Range and Gigahertz MaximumSpeed,” IEEE J. Solid-State Circuits, vol. 23, pp. 474–479, April 1988.

[4] B. Razavi et al., “A 3-GHz 25-mW CMOS Phase-Locked Loop,” Dig. of Symposium on VLSICircuits, pp. 131–132, June 1994.

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6 Chap. 1. Introduction to RF and Wireless Technology

[5] M. Soyuer et al., “A 3-V 4-GHz nMOS Voltage-Controlled Oscillator with IntegratedResonator,” IEEE J. Solid-State Circuits, vol. 31, pp. 2042–2045, Dec. 1996.

[6] B. Kleveland et al., “Monolithic CMOS Distributed Amplifier and Oscillator,” ISSCC Dig.Tech. Papers, pp. 70–71, Feb. 1999.

[7] H. Wang, “A 50-GHz VCO in 0.25-μm CMOS,” ISSCC Dig. Tech. Papers, pp. 372–373,Feb. 2001.

[8] L. Franca-Neto, R. Bishop, and B. Bloechel, “64 GHz and 100 GHz VCOs in 90 nm CMOSUsing Optimum Pumping Method,” ISSCC Dig. Tech. Papers, pp. 444–445, Feb. 2004.

[9] E. Seok et al., “A 410GHz CMOS Push-Push Oscillator with an On-Chip Patch Antenna”ISSCC Dig. Tech. Papers, pp. 472–473, Feb. 2008.

[10] B. Razavi, “A 300-GHz Fundamental Oscillator in 65-nm CMOS Technology,” Symposiumon VLSI Circuits Dig. Of Tech. Papers, pp. 113–114, June 2010.

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INDEX

AAC coupling

constant capacitors, 490direct-conversion receivers, 183–184, 187mixers, 412–413, 867predrivers, 865, 867transformers, 470VCOs, 526, 573

Acceptable quality, 59Accumulation-mode MOS varactors, 486Accuracy

DAC, 739I/Q calibration, 232inductor equations, 438–439input matching, 72integer-N frequency synthesizers, 656output matching, 73

ACPR in power amplifiers, 756–758Acquisition range of PLLs, 611, 614Active mixers

with current-source helpers, 393–394downconversion, 368–369

conversion gain, 370–377double-balanced, 369–370linearity, 387–392noise, 377–387

with enhanced transconductance, 394–397with high IP2, 397–405with low flicker noise, 405–408upconversion, 416–420

design procedure, 421–424mixer carrier feedthrough, 420–421

ADCs (analog-to-digital converters) in receiversAGC range, 836

baseband, 858–859direct-conversion, 186resolution, 837

Additive noiseAM, 94conversion to phase noise, 550–552, 554I/Q mismatches, 198

Adjacent-channel interferenceGSM, 135IEEE802.11, 149low-IF receivers, 214wideband CDMA, 140, 142–143

ADS simulator, 439AGC in receivers

design, 856–861range, 836–837

Aliasingpassive downconversion mixers, 360–361power amplifiers, 798

Aligned resultants in AM signals, 97Alignment of VCO phase, 600–601AM (amplitude modulation), 93–94

direct-conversion receivers, 189–190heterodyne receivers, 172–173tail noise, 567, 569–570

AM/AM conversion, 757–758AM/PM conversion (APC)

concepts, 33–35polar modulation, 794–795, 799–801power amplifiers, 757–758

Ampere’s law, 452Amplitude

direct-conversion receivers, 196in modulation, 92

889

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890 Index

Amplitude (Contd.)oscillators, 505–507power amplifiers, 757–758VCO variation, 532

Amplitude modulation (AM), 93–94direct-conversion receivers, 189–190heterodyne receivers, 172–173tail noise, 567, 569–570

Amplitude shift keying (ASK), 100, 105Analog modulation, 93

amplitude, 93–94phase and frequency, 95–99

Analog-to-digital converters (ADCs) in receiversAGC range, 836baseband, 858–859direct-conversion, 186resolution, 837

Analysis and Simulation of Spiral Inductors andTransformers (ASITIC) simulator, 437–439

Analytic signals, 202AND gates

current-steering circuits, 683dual-modulus dividers, 677, 880phase/frequency detectors, 613–614

Antennascellular systems, 122duplexing method, 130LNA interface, 258–259thermal noise, 42, 49–50

Anti-phase coupling, 582, 584–586, 592APC (AM/PM conversion)

concepts, 33–35polar modulation, 794–795, 799–801power amplifiers, 757–758

ASITIC (Analysis and Simulation of Spiral Inductorsand Transformers) simulator, 437–439

ASK (amplitude shift keying), 100, 105Asymmetries

cascode power amplifiers, 817direct-conversion receivers, 179, 181, 187–189heterodyne receivers, 172–174I/Q mismatches, 194LO self-mixing, 357sequence-asymmetric polyphase filters, 221single-balanced mixers, 398–399transformers, 471, 473–474

Attenuationchannel, 92image, 224–225

Auxiliary amplifiers in PLLs, 634–635Available noise power, 42Available power gain, 54Average power in noise, 36Axis of symmetry, inductors along, 465

BBalance systems, 12Baluns

differential LNAs, 315–324outphasing, 810power amplifiers, 758–760, 764, 767

Band-pass filtersdifferential LNAs, 315FDD, 123–124heterodyne transmitters, 244–245noise spectrum, 37–39, 58Q, 157transceivers, 158–159transmitter overview, 156

Band selection in transceivers, 157–159Band switching LNAs, 262, 312–314Bandwidth

divide-by-2 circuits, 693–696efficiency, 93fractional, 176frequency synthesizers, 663, 842–843, 883LNAs, 261–263, 304offset PLLs, 672outphasing, 805passive upconversion mixers, 410–411PLL-based modulation, 667–668polar modulation, 794, 801–802power amplifiers, 757, 865QPSK, 107VCO phase noise, 645–646

Barkhausen’s criteria, 503–505, 512, 544,583

BasebandADC resolution, 858–859AGC gain, 859DACs, 409description, 91–92mixers, 337, 409, 414offset, 414outphasing, 804polar modulation, 796–797pulses, 103, 227QPSK signals, 108–109

Basic design concepts, 7dynamic range, 60–62noise. See Noise and noise figure (NF)nonlinear dynamic systems, 75–77nonlinearity. See Nonlinearitypassive impedance transformation, 62–63

matching networks, 65–71quality factor, 63series-to-parallel conversions, 63–65

scattering parameters, 71–75sensitivity, 59–60, 131

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Index 891

time variance, 9–12units, 7–9Volterra series, 77–85

Basis functions, 105BER. See Bit error rate (BER)Bias

LNA common-gate stage, 280–281LNA nonlinearity calculations, 325–326phase noise current source, 565–570

Bipolar transistor noise, 46Bit error rate (BER)

GSM, 132I/Q mismatch, 198power amplifiers, 756receiver noise, 834in sensitivity, 59, 346transmitters, 838wireless standards, 131

Blind zones with VCOs, 535–536, 846,869

BlockingBluetooth tests, 145–146GSM requirements, 133–134with interferers, 19wideband CDMA, 140–142

Bluetooth standardfrequency channels, 655GFSK for, 113ISM band, 130LOs, 660overview, 143–147receivers, 22–24

Bode plotscharge pumps, 619–620PLLs, 608–609

Bond wirescascode CS stage, 284–285coupling between, 430–431differential LNAs, 320, 322MOS capacitors, 491outphasing, 810power amplifiers, 755, 758–759, 815

Bootstrapping, cascode power amplifiers with,816–817

Bottom-biased PMOS oscillators, 573Bottom-plate capacitance

inductors, 440parallel-plate capacitors, 494VCOs, 534, 879

Brickwall spectrum, 103Broadband model of inductors, 457Broadband noise, 670–671Buffers

LOs, 380–381, 413, 499, 576–577

PLLs, 602, 607, 668polar modulation, 794, 824

Bypass, LNA, 312

CCalibration of image-reject receivers, 213Capacitance and capacitors

AM/PM conversion, 795, 799constant, 490–495divide-by-2 circuits, 690, 692, 694–696inductors, 437, 439–444, 461–463, 466–469input impedance, 9integer-N synthesizer loop design, 883–885large-signal impedance matching, 780–781LNAs

band switching, 312–313common-gate stage, 280–282common-source stage, 269–271, 286–287,

291–293differential, 321gain switching, 308–309input, 851noise-cancelling, 301, 303

matching networks, 65–69metal-plate, 493–495Miller dividers, 703mixers

downconversion, 352, 376–377, 382–383,500

with enhanced transconductance, 395–397with high IP2, 398, 403–404port-to-port feedthrough, 339–340upconversion, 410, 415–416, 422

MOS, 491–493oscillators, 571

cross-coupled, 514–515drive capability, 498–499

outphasing, 808–810parallel-plate, 493–495phase noise, 555–557PLL higher-order loops, 625–626power amplifiers, 754

cascode, 815–817class B, 765class E, 772–774polar modulation, 792, 795–796positive-feedback, 819–820predrivers, 864

quality factor, 63T-lines, 477transformers, 470–475varactors, 483–490VCOs. See Voltage-controlled oscillators

(VCOs)

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892 Index

Capacitive couplingactive mixers, 397, 403–404divide-by-2 circuits, 692integer-N synthesizers, 692, 700, 704LNA feedback paths, 304LO interface, 576–577power amplifiers, 865substrate loss, 450–452, 457–458, 466transformers, 470–471, 474–475VCOs, 527, 574, 871–872

Capacitively-degenerated differential pairs,591

Carrier amplifiers, 811Carrier feedthrough

active mixers, 420–421passive mixers, 413–416

Carrier frequency, 91Carrier leakage

direct-conversion transmitters, 232–234heterodyne transmitters, 244

Carrier power in phase noise, 539Cartesian feedback, 786–787Cascade image rejection, 225Cascaded loops and modulators, 730–732Cascaded stages

low-IF receivers, 222noise figure, 52–56nonlinear, 29–33transceiver filters, 158

Cascode stagesLNAs, 284–286

common-gate, 277–279design procedure, 291–296differential, 318–321gain switching, 310–311noise factor, 287–291pad capacitance, 286–287

power amplifiers, 776–779, 815–819CCI (co-channel interference), 120CCK (complementary code keying), 150CDMA (code-division multiple access), 126

direct-conversion transmitters, 232–233direct sequence, 126–129IS-95, 137–139wideband, 139–143

Cellular systems, 119–120antenna diversity, 122co-channel interference, 120delay spread, 122–123hand-offs, 120–121interleaving, 123path loss and multipath fading, 121–122transmitters, 91

Center frequency in LC VCOs, 571CG (common-gate) stage in LNAs, 272–277

cascode stage, 277–279design procedure, 279–284gain switching LNAs, 306variants, 296–300

CG differential LNAs, 315–318Chang-Park-Kim dividers, 878, 880Channel charge injection, 631Channel-length modulation

charge pumps, 633–634LNA common-gate stage, 275

Channel selectionvs. image rejection, 166–168transceiver architectures, 157–159

Channelization standards, 130Channels

attenuation, 92integer-N synthesizers, 656, 661, 664mixer bandwidth, 500mobile RF communications, 119overlapping frequencies, 150

Characteristic impedancecoplanar lines, 482microstrips, 479–482striplines, 483

Charge-and-hold output in charge pumps, 616Charge equations for varactors, 487Charge injection, 630–632Charge pumps, 614–615

channel-length modulation, 633–634charge injection and clock feedthrough,

630–632CPPLLs, 615–620, 622–625fractional-N synthesizers, 733–738integer-N synthesizers, 883–884regulated cascodes, 634–635VCOs, 522, 525

Chips, CDMA, 127–128Chireix’s cancellation technique, 808–809Circuit simulators

integer-N synthesizers, 884–886power amplifiers, 757varactors, 487

Circular inductors, 435Clapp oscillators, 517Class A power amplifiers

with harmonic enhancement, 771–772overview, 760–764

Class-AB latches, 691Class AB power amplifiers, 767Class B power amplifiers, 764–767Class C power amplifiers, 768–770

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Index 893

Class E power amplifiers, 772–775Class F power amplifiers, 775–776Clock feedthrough, 630–632Close-in phase noise, 539–540Closed-loop control

IS-95 CDMA, 138polar modulation, 793

Closed-loop transfer functionsinteger-N synthesizers, 666PLLs, 607, 619

CML (current-mode logic), 683–687CMOS technology, 2–3

LNA common-gate stage, 275oscillator frequency range, 498ring oscillators, 507

Co-channel interference (CCI), 120Code-division multiple access (CDMA), 126

direct-conversion transmitters, 232–233direct sequence, 126–129IS-95, 137–139wideband, 139–143

Cognitive radios, 199Coherent detection

IS-95 CDMA, 137QPSK, 110

Collector efficiency in power amplifiers, 755, 761,766

Colpitts oscillators, 517Common-gate (CG) stage in LNAs, 272–277

cascode stage, 277–279design procedure, 279–284gain switching LNAs, 306variants, 296–300

Common-mode current in mixers, 373–374Common-mode input in LOs, 349Common-mode noise

active downconversion mixers, 383active mixers with low flicker noise, 405

Common-mode stability in power amplifiers,866–867

Common-source stagesLNAs

with inductive degeneration, 284–296with inductive load, 266–269with resistive feedback, 269–272

memoryless systems, 12Communication concepts, 91

analog modulation, 93–99considerations, 91–93digital modulation. See Digital modulationDPSK, 151–152mobile RF, 119–123multiple access techniques, 123–130

spectral regrowth, 118–119wireless standards. See Wireless standards

Compact inductor model, 458Comparators in power amplifiers, 824Compensation in fractional-N synthesizers, 718Complementary code keying (CCK), 150Compression

gain, 16–20LNAs, 851–852in mixer linearity, 388–392power amplifiers, 757–758, 863–864receivers, 856upconverters, 868–869wideband CDMA, 140

Concentric cylinders model, 457Conduction angles, 764, 768–769Constant capacitors, 490–495Constant-envelope modulation, 112Constant-envelope waveforms, 802Constellations

dense, 114–115signal, 105–112

Continuous-time (CT) approximationcharge pumps, 616type-II PLLs, 622–623

Continuous tuning, VCOs with, 524–532Conversion gain

Hartley receivers, 253LO, 349, 501Miller dividers, 701–703mismatches, 226mixers

current-source helpers, 393downconversion, 339, 348, 350–356, 368–382linearity, 388–391noise, 357–362, 408, 567power amplifiers, 790upconversion, 409–410, 414, 416, 868

Conversionsadditive noise to phase noise, 550–552, 554AM/AM, 757–758AM/PM

concepts, 33–35polar modulation, 794–795, 799–801power amplifiers, 757–758

current and voltage, 368–369series-to-parallel, 63–65

Convolution in phase noise, 560–561Coplanar lines, 482–483Cosine signals in image-reject receivers, 200Cost trends, 2Counters in pulse swallow dividers, 674–676Coupled oscillators, 583–589

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894 Index

Couplingbetween bond wires, 430capacitance. See Capacitive couplingmagnetic. See Magnetic couplingquadrature oscillators, 581, 590

CPPLLs (charge-pump PLLs), 615–620continuous-time approximation, 622–623frequency-multiplying, 623–625

Cross-coupled oscillators, 511–517open-loop model, 545, 547–548phase noise computation, 555power amplifiers, 820tail noise, 565–566time-varying resistance, 553

Cross-coupled pairsactive mixers with low flicker noise, 406Norton noise equivalent, 548–549VCOs, 530–531

Cross modulationdescription, 20–21wideband CDMA, 140–141

Cross-talk, 229Crystal oscillators

integer-N synthesizer design, 881phase noise, 644

CT (continuous-time) approximationcharge pumps, 616type-II PLLs, 622–623

Current crowding effect, 448–450Current domain in single-balanced mixers, 356Current-driven passive mixers, 366–368Current impulse

oscillators, 509in phase noise, 557–559

Current mirroringactive mixers, 395–396DACs, 741divide-by-2 circuits, 692VCOs, 874–876

Current-mode DAC implementation, 741Current-mode logic (CML), 683–687Current sources

helpers, 393–394offset cancellation by, 186power amplifiers, 752

Current-steeringcross-coupled oscillators, 517divider design, 683–689LO interface, 499, 577mixer linearity, 388prescalers, 682

Current-to-voltage (I/V) characteristic of chargepumps, 883–884

Current-to-voltage (I/V) conversion, 368–369

Currents, nonlinear, 81–85Cyclostationary noise, 552–553, 565

DD flipflops in phase/frequency detectors, 613DACs (digital-to-analog converters)

direct-conversion receivers, 185–187direct-conversion transmitters, 233–234feedforward, 738–742upconversion mixer interfaces, 409

Damping factorclass E power amplifiers, 773–774divide-by-2 circuits, 693integer-N synthesizers, 665–666, 883PLL transfer functions, 608

Dangling bonds, 44Data rates, 130, 136–137dBm, 8–9DC offsets

active mixers with high IP2, 398–400AGC, 859direct-conversion receivers, 181–187port-to-port feedthrough, 340–341

DCOs (digitally-controlled oscillators), 536DCRs. See Direct-conversion receiversDCS1800 standard, 132Decibels (dB), 7–9Degenerated differential pairs, 332–333Degenerated LNA common-source stages

inductive degeneration, 284–296nonlinearity calculations, 325–329

Degeneration capacitors, 403–404, 591Delay spread in cellular systems, 122–123Delayed replicas in IS-95 CDMA, 138Delays

divider design, 681, 709–712fractional-N synthesizers, 723–724integer-N synthesizers, 665–667OFDM, 115–117PFD/CP, 629polar modulation, 793–794, 801

Delta modulators (DMs), 824–825Demodulation, 92

IS-95 CDMA, 137QPSK, 110

Demultiplexers in QPSK, 107Dense constellations, 114–115Desensitization, 19Design

active upconversion mixers, 421–424basic concepts. See Basic design conceptsdividers. See DividersLNA cascode CS stage with inductive

degeneration, 291–296

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Index 895

LNA common-gate stage, 279–284oscillators, 571–575power amplifier. See Power amplifiers (PAs)transceiver example. See Transceiverstype-II PLLs, 646–647

Despreading in CDMA, 128DET (double-edge-triggered) flipflops, 742–743Detectability, 92Detection, 92

IS-95 CDMA, 137PFDs. See Phase/frequency detectors (PFDs)phase detectors, 597–600polar modulation, 794, 799–800, 826power amplifier linearization, 789–790QPSK, 110

Deterministic mismatchesfractional-N synthesizers, 737up and down current, 637

Device noisebipolar transistors, 46MOS transistors, 43–46resistors, 40–43

Differential circuits, symmetric inductors in,460–461, 463–464

Differential LNAs, 314–315baluns, 317, 321–324common-gate, 315–318common-source, 318–321

Differential LO phasesmixers, 348, 372, 374, 386oscillators, 501

Differential mixers, 402Differential noise, 406, 853Differential oscillators, 518, 585, 589Differential pairs

charge pumps, 632current-steering circuits, 683downconversion mixers, 500input/output characteristics, 12–13LNAs, 331–332oscillators, 507–508, 591

Differential power amplifiers, 758–760Differential PSK (DPSK), 151–152Digital modulation

GMSK and GFSK, 112–113intersymbol interference, 101–104OFDM, 115–118overview, 99–100QAM, 114–115quadrature, 107–112signal constellations, 105–107

Digital-to-analog converters (DACs)direct-conversion receivers, 185–187direct-conversion transmitters, 233–234

feedforward, 738–742upconversion mixer interfaces, 409

Digitally-controlled oscillators (DCOs), 536Dimensions of inductors, 433–434Diode-connected devices

active mixers with low flicker noise, 405–406power amplifiers, 816–817VCOs, 525–526

Direct-conversion mixers, 344Direct-conversion receivers, 179

DC offsets, 181–187even-order distortion, 187–191flicker noise, 191–194I/Q mismatch, 194–199LO leakage, 179–184mixing spurs, 199noise figure, 346–348

Direct-conversion transmitters, 227–229carrier leakage, 232–234I/Q mismatch, 229–232mixer linearity, 234–235mixers, 339–342modern, 238–243noise, 238oscillator pulling, 237–238TX linearity, 235–236

Direct sequence CDMA, 126–129Direct sequence SS (DS-SS) communication, 127Discrete-time (DT) systems, 622–623Discrete tuning in VCOs, 532–536Distortion

direct-conversion receivers, 187–191duty-cycle, 398harmonic. See Harmonics and harmonic distortionintersymbol interference, 101–104outphasing, 808power amplifier linearization, 787–788

Distributed capacitancedividers, 694inductors, 440LNA common-source stage, 293varactors, 488–489

Distributed inductor model, 458Distributed resistance in varactors, 487–489Dithering in fractional-N synthesizers, 728Diversity

antenna, 122IS-95 CDMA, 138

Divide-by-1.25 circuits, 746Divide-by-1.5 circuits, 743Divide-by-2 circuits, 878–880

designing, 689–697direct-conversion transmitters, 239–240dual-modulus dividers, 677

Page 39: Razavi Micro

896 Index

Divide-by-2 circuits (Contd.)heterodyne receivers, 175Miller dividers, 706–707pulse swallow dividers, 675–676true single-phase clocking, 697–698

Divide-by-2/3 circuitsdual-modulus dividers, 679pulse swallow dividers, 676–677

Divide-by-3 circuitsdual-modulus dividers, 677–678Miller dividers, 706–707

Divide-by-3/4 circuit, 680, 881–882Divide-by-4 circuits, 177–178Divide-by-8/9 circuit, 680Divide-by-15/16 circuit, 681–682Dividers, 673–674

divide-by-2 circuit, 878–880divider delay and phase noise, 709–712dual-modulus, 677–682, 880–881frequency multiplication, 609–611injection-locked, 707–709LO path, 499logic styles, 683

current-steering circuits, 683–689divide-by-2 circuits, 689–697true single-phase clocking, 697–699

Miller, 699–707PLLs, 611, 672prescaler modulus, 682–683pulse swallow, 673–677

DMs (delta modulators), 824–825Doherty power amplifiers, 811–813, 818–819Double-balanced mixers, 348–350

active downconverters, 369–370active upconverters, 416capacitive degeneration, 403–404input offset, 399–400Miller dividers, 700noise, 362–363, 381passive downconverters, 351–352passive upconverters, 411, 414polar modulation power amplifiers, 826sampling, 356voltage conversion gain, 377

Double-edge-triggered (DET) flipflops, 742–743Double-quadrature downconversion

low-IF receivers, 224–226Weaver architecture, 213

Double-sideband (DSB) mixers, 867Double-sideband (DSB) noise figure, 344, 853Double-transformer topology, 822Down currents and pulses

charge pumps, 614–615, 630–633, 635–637fractional-N synthesizers, 733–734

integer-N synthesizers, 883PLL higher-order loops, 625, 627quantization noise, 739

Down skew in PFD/CP, 627–630Downbonds, 285Downconversion and downconversion mixers, 339

active, 368–369conversion gain, 370–377double-balanced, 369–370linearity, 387–392noise, 377–387

design, 851–856heterodyne receivers, 160–164, 168–170image-reject receivers, 206, 210LO ports, 500low-IF receivers, 219–221, 224–226noise figures, 343passive, 350

current-driven, 366–368gain, 350–357input impedance, 364–367LO self-mixing, 357noise, 357–364

phase noise, 540–541and self-corruption of asymmetric signals,

173–175Weaver architecture, 213

Downlinks, 119DPSK (differential PSK), 151–152DR (dynamic range), 60–62Drain capacitance in large-signal impedance

matching, 780Drain current

LNA common-gate stage, 280power amplifiers, 768, 771, 773, 776

Drain efficiency in power amplifiers, 755Drive capability of oscillators, 498–499DS-CDMA power control, 128–129DSB (double-sideband) mixers, 867DSB (double-sideband) noise figure, 344, 853DT (discrete-time) systems, 622–623Dual downconversion, 168–170Dual-gate mixers, 374Dual-modulus dividers, 677–682, 880Dual-modulus prescalers, 674–675Dummy switches for charge pumps, 631Duplexer filters

FDD systems, 124offset PLLs, 671

Duplexers and duplexing methodsantennas, 130time and frequency division duplexing, 123–124transceivers, 158–159

Duty cycle distortion, 398

Page 40: Razavi Micro

Index 897

Dynamic dividers, 699–702with inductive load, 702–705moduli with, 705–707

Dynamic logic in divide-by-2 circuit, 878Dynamic nonlinearities, 28Dynamic range (DR), 60–62Dynamic systems, 14

EEddy currents in inductors, 448–449, 452–455, 466EDGE (Enhanced Data Rates for GSM Evolution)

systemsdescription, 136–137polar modulation, 801–802

Edge-triggered devicesDET flipflops, 742–743phase/frequency detectors, 612–613

EER (envelope elimination and restoration), 790–793Efficiency

modulation, 93power amplifiers, 755–756

class A, 760–764, 771–772class AB, 767class B, 764–767class C, 768–771class E, 772–775class F, 775–776

8-PSK waveforms, 136–137Electrostatic discharge (ESD) protection devices,

280Embedded spirals

high-IP2 LNAs, 323–324transformers, 471

Encoding operations in DS-CDMA, 127End points in fractional-N synthesizers, 736Enhanced Data Rates for GSM Evolution (EDGE)

description, 136–137polar modulation, 801–802

Enhanced transconductance, active mixers with,394–397

Envelope-controlled loads, 793Envelope detection

polar modulation, 794, 799–800, 826power amplifier linearization, 789–790

Envelope elimination and restoration (EER),790–793

Envelopespolar modulation, 793, 795, 825–826power amplifier linearization, 788–790QPSK, 110

Error cancellation loops, 783Error vector magnitude (EVM)

description, 106–107receivers, 838

ESD (electrostatic discharge) protection devices,280

Even-order harmonics, 15, 187–191EVM (error vector magnitude)

description, 106–107receivers, 838

Excess frequency, 95Excess phase in VCOs, 581Excessive noise coefficient, 43Exclusive-NOR (XNOR) gates, 152Exclusive-OR (XOR) gates

current-steering circuits, 685–686phase detectors, 598–599PLLs, 603reference doubling, 743

Expansive characteristic, 17Extrapolation, intermodulation, 27

FFading, multipath, 121–123Far-out phase noise

description, 539–540offset PLLs, 672

Faraday’s lawinductors, 448magnetic coupling to substrate, 452

Fast Fourier Transform (FFT), 391FDD (frequency-division duplexing), 123–124FDMA (frequency-division multiple access), 125Feedback

direct-conversion transmitters, 232–233dividers. See Dividersfractional-N synthesizers, 716, 718–720, 722–723,

725integer-N synthesizers, 661LNAs

common-gate, 296–297gain switching, 311noise-cancelling, 300–301resistance, 851

offset cancellation by, 185oscillators, 502–508, 513, 582–584polar modulation, 793, 798–800power amplifiers, 759, 783, 786–787VCO phases, 601

Feedforwardcommon-gate LNAs, 298–300gain switching LNAs, 311power amplifier linearization, 783–786quantization noise, 738–742

Feedthrough, mixeractive upconversion, 420–421passive upconversion, 413–416port-to-port, 339–343

Page 41: Razavi Micro

898 Index

FFT (Fast Fourier Transform), 391FH (frequency hopping) in CDMA, 129–130Field simulations for inductors, 439Figure of merit (FOM) of VCOs, 570–571Filters, 101

active mixers with high IP2, 402Bluetooth, 143–144differential LNAs, 315direct-conversion receivers, 179, 184duplexer, 124FDD, 123–124fractional-N synthesizers, 716, 738front-end band-pass, 124Gaussian, 112, 143–144heterodyne transmitters, 244–245image-reject, 166, 206integer-N synthesizers, 665LNAs with high-IP2, 323–324low-IF receivers, 217–224low-pass, 101Miller dividers, 699–701, 705noise, 37–40, 58PLLs, 603, 606, 625–627, 671polar modulation, 824–826power amplifier linearization, 790Q, 157transceivers, 157–159transmitter overview, 156VCOs, 601, 875–876

First-order dependence in AM/PM conversion, 34First-order � modulators, 726Flat fading, 123Flat phase noise profiles, 644Flicker noise, 44–45

active mixerswith current-source helpers, 394downconversion, 385–387low, 405–408

direct-conversion receivers, 191–194low-IF receivers, 215passive downconversion mixers, 366phase, 563–564, 566quadrature oscillators, 591–592receiver design, 853–854VCOs, 642

Floating resonators in VCOs, 531Floating switches in VCOs, 535, 870FM (frequency modulation), 95–96

frequency synthesizer spurs, 843–844heterodyne receivers, 173narrowband approximation, 96–98

FNSs. See Fractional-N synthesizers (FNSs)FOM (figure of merit) in VCOs, 570–571Forward channels, 119

Four-level modulation schemes, 92Fourier coefficients

cascode output stages, 776power amplifiers, 770

Fourier seriesAM/PM conversion, 34, 569flicker noise, 563–564LO waveforms, 368reference doubling, 743–744VCOs, 580

Fourier transformsfractional-N synthesizers, 716–717mixer gain, 352–353mixer impedance, 364power spectral density, 37quantization noise, 748–749VCO sidebands, 628Volterra series, 77–81

Fractional bandwidthIF, 176LNA systems, 262

Fractional dividers, 742–743Fractional-N synthesizers (FNSs), 715

basic concepts, 715–718basic noise shaping, 722–728charge pump mismatch, 733–738higher-order noise shaping, 728–732modulus randomization, 718–721out-of-band noise, 732–733quantization noise, 738–749

Fractional spurs, 716Free-running VCOs, 655Frequencies. See also Bandwidth

cellular system reuse, 119–120divide-by-2 circuits, 693–694injection-locked dividers, 709integer-N synthesizers, 664, 881LNAs, 259

bandwidth, 261–263cascode stage, 294–296common-gate stage, 278–279

Miller dividers, 704mixers. See Mixersoscillators, 497–498, 503–507, 514, 517phase detectors, 597–598, 612phase noise, 537–538, 566PLLs, 605–606polar modulation, 794system-level considerations, 844–848VCOs, 519–520, 526, 532, 571, 600wireless standards, 130

Frequency-dependent phase shift, 504, 507Frequency-dependent values, 73Frequency detectors (FDs) in PLLs, 602

Page 42: Razavi Micro

Index 899

Frequency deviation, 95Frequency diversity

cellular systems, 122IS-95 CDMA, 138

Frequency division, multiphase, 745–748Frequency-division duplexing (FDD), 123–124Frequency-division multiple access (FDMA), 125Frequency hopping (FH), 129–130Frequency-locked loops (FLLs), 602Frequency modulation (FM), 95–96

frequency synthesizer spurs, 843–844heterodyne receivers, 173narrowband approximation, 96–98

Frequency multiplication, 609–611, 623–625Frequency noise, 732Frequency responses

LNA systems, 262oscillators, 512VCO phase noise, 645

Frequency-selective fading, 123Frequency shift keying (FSK), 100

direct-conversion receivers, 184, 197–198noise, 105–106PLLs, 605–606

Frequency synthesizers, 498fractional-N. See Fractional-N synthesizers

(FNSs)integer-N. See Integer-N synthesizerssystem-level considerations, 840–844

Friis’ equationLNAs, 264noise, 54–55, 57–58

Fringe capacitance in inductors, 439–440, 461, 463Fringe capacitors

parallel-plate capacitors, 495VCOs, 529–530

Front-end band-pass filters, 124Front-end band-select filters, 158FSK (frequency shift keying), 100

direct-conversion receivers, 184, 197–198noise, 105–106PLLs, 605–606

Full-duplex LNA systems, 260–261Full scale in dynamic range, 60Fully-integrated power amplifiers, 770Fundamentals in harmonic distortion, 15, 34

GGain

AGCdesign, 856–861range, 836–837

conversion. See Conversion gaincurrent-steering circuits, 686

LNAs, 257–258, 304, 850–852Miller dividers, 703oscillators, 504–507PLLs, 597, 601–602, 604power amplifiers, 790, 863transmitter, 838–839VCOs, 518, 601–602, 604

Gain compression, 16–20, 388–392Gain error in DACs, 741Gain mismatch

direct-conversion receivers, 196direct-conversion transmitters, 231–232, 241image-reject receivers, 209

Gain switchingLNAs, 305–312receivers, 837

Gap capacitance, 466–467Gate capacitance

divide-by-2 circuits, 692power amplifiers, 815

Gate-induced noise current, 43–44Gate-referred noise voltage, 256Gate switching in PLLs, 636Gaussian distribution, 122Gaussian filters

Bluetooth, 143–144impulse response, 112

Gaussian frequency shift keying (GFSK)Bluetooth, 143description, 112–113direct-conversion transmitters, 234–235

Gaussian minimum shift keying (GMSK)Bluetooth, 143description, 112–113direct-conversion transmitters, 234–235

Generic transmitter upconversion requirements, 408Gilbert cell in upconversion mixers, 418Global System for Mobile Communication (GSM)

adjacent-channel interference, 135blocking requirements, 133–134description, 132–133EDGE, 136–137intermodulation requirements, 134–135transmitters, 135–136, 670

Gm oscillators, 516–517GMSK (Gaussian minimum shift keying)

Bluetooth, 143description, 112–113direct-conversion transmitters, 234–235

Ground inductances in LNAs, 260, 281Grounded shield inductors, 435, 466–467GSM. See Global System for Mobile Communication

(GSM)GSM/EDGE mask margins, 801

Page 43: Razavi Micro

900 Index

HHand-offs

cellular systems, 120–121IS-95 CDMA, 139

Handheld units, 119Hard transistors, 776Harmonics and harmonic distortion, 14–16

AM/PM conversion, 34class A power amplifiers, 771–772class E power amplifiers, 775class F power amplifiers, 775–776direct-conversion transmitters, 241heterodyne transmitters, 244–246narrowband systems, 25phase noise, 564–565

Hartley architecturecalibration, 213image-reject receivers, 205–210low-IF receivers, 215–216

Heterodyne receivers, 160–161dual downconversion, 168–170high-side and low-side injection, 164–166image problem, 161–164image rejection, 166–168mixers, 342sliding-IF, 174–178zero second IFs, 171–174

Heterodyne transmitters, 244carrier leakage, 244mixing spurs, 245–248

HFSS simulator for inductors, 439High currents in power amplifiers, 754–755High-efficiency power amplifiers, 770

class A, 771–772class E, 772–775class F, 775–776

High IP2, mixers with, 397–405High-IP2 LNAs, 313–314

differential, 314–315baluns, 317, 321–324common-gate, 315–318common-source, 318–321

improvement methods, 323–324High-pass filters (HPFs)

direct-conversion receivers, 184image-reject receivers, 203, 206LNAs with high-IP2, 323–324mixers with high IP2, 402

High-side injection, 164–166Higher harmonics in phase noise, 564–565Higher-order noise shaping, 728–732Higher-order PLL loops, 625–627Hilbert transform

image-reject receivers, 201, 203–206low-IF receivers, 215–217

Hold-mode noise, 359–362Homodyne architecture, 179HPFs. See High-pass filters (HPFs)HSPICE simulator for varactors, 487

II/Q mismatches

frequency planning, 848receivers, 194–199, 837–838transmitters, 229–232, 241, 244, 839–840

I/V (current-to-voltage) characteristic of chargepumps, 883–884

I/V (current-to-voltage) conversion,368–369

IEEE802.11a/b/g standard, 147–151IF (intermediate frequency)

heterodyne receivers, 160–162, 168–169low-IF receivers, 214–217zero second, 171–178

IF ports, 337IIP3 (input third intercept points), 26ILDs (injection-locked dividers), 707–709IM. See Intermodulation (IM)Image issues

heterodyne receivers, 161–164, 166–168low-IF receivers, 224–225

Image-reject receivers (IRRs), 200, 838908 phase shift, 200–205calibration, 213Hartley architecture, 205–210low-IF, 215–217Weaver receivers, 210–213

Image-to-signal ratio, 208Impedance, 9

charge pumps, 634–635coplanar lines, 482current sources, 634–635divide-by-2 circuits, 692–693downconversion mixers, 500large signals, 780–781LNAs, 258–260, 263

common-gate, 276, 296–298common-source, 267, 284–285gain switching, 307, 309

matching networks, 69microstrips, 479–482mixers, 357, 364–367, 856and noise, 48, 52, 54–56oscillators, 503, 510PLLs, 634, 668power amplifiers, 780–782, 809, 812–813,

821T-lines, 478

Impedance transformationpassive, 62–63

Page 44: Razavi Micro

Index 901

matching networks, 65–71quality factor, 63series-to-parallel conversions, 63–65

power amplifiers, 753Impulse sensitivity function in phase noise, 559,

563IMT-2000 air interface, 139–143In-band blockers in GSM, 133In-band interferers, 158In-band loss, 158In-band noise in fractional-N synthesizers, 728In-channel IP3, 835In-loop PLL modulation, 667–669In-phase coupling, 582, 585, 588, 592Incident waves, 71–73Inductance and inductors

basic structure, 431–434capacitive coupling to substrate, 450–452,

457–458cross-coupled oscillators, 514divide-by-2 circuits, 692–696equations, 436–439geometries, 435with ground shields, 466–467LNAs

common-gate, 281common-source, 266–269, 291, 294differential, 320–322noise-cancelling, 301, 305parasitic, 260

loss mechanisms, 444–455magnetic coupling to substrate, 452–455,

457–458metal resistance, 444–448Miller dividers, 702–705mixers

active upconversion, 416, 422enhanced transconductance, 396–397passive upconversion, 412–413

modeling, 455–460off-chip, 430–431one-port oscillators, 511outphasing, 808–810parasitic capacitances, 439power amplifiers, 752–755, 765–767, 815, 817skin effect, 448–450stacked, 467–470symmetric, 460–466T-lines, 477VCOs, 520–521, 523, 571

Inductive degeneration in LNAs, 284–296, 310Industrial-scientific-medical (ISM) band, 130Infradyne system, 164Injected noise, 562–563Injection-locked dividers (ILDs), 707–709

Injection-locked power amplifiers, 820–821Injection locking in quadrature oscillators,

592–593Injection pulling between oscillators, 237, 589Input capacitance

cross-coupled oscillators, 514LNAs, 301, 303, 851power amplifiers, 754, 819, 864

Input impedance, 9LNAs, 258–260, 263

common-gate, 276, 296–298common-source, 267, 284–285gain switching, 307, 309

mixers, 364–367, 856one-port oscillators, 510PLL-based modulation, 668

Input level range in wireless standards, 131Input matching

LNAs, 263–266common-gate, 299common-stage, 287, 292–294gain switching, 307, 310noise-cancelling, 304

power amplifiers, 814Input/output characteristics of Doherty power

amplifiers, 811Input-referred noise

active downconversion mixers, 381–384, 390LNAs, 256–257modeling, 46–48, 50sampling mixers, 359, 362–363

Input reflection coefficient, 74Input resistance in LNAs, 308, 851Input return loss in LNAs, 258–259Input third intercept points (IIP3), 26Instantaneous frequency, 95Integer-N synthesizers, 655, 869

basic, 659–661considerations, 655–659dividers. See Dividersloop design, 882–886PLL-based modulation, 667–673settling behavior, 661–664spur reduction techniques, 664–667VCO design, 869–877

Integration trends, 2Integrators

DAC, 739–740fractional-N synthesizers, 723–724, 728VCOs, 581

Inter-spiral capacitance in inductors, 468–469Interference

adjacent-channel, 135co-channel, 120intersymbol, 101–104, 115–116

Page 45: Razavi Micro

902 Index

Interfererswith compression, 18–19with cross modulation, 20–21direct-conversion receivers, 187high-IP2 LNAs, 324integer-N frequency synthesizers, 657with intermodulation, 21–23mixers, 341transceivers, 156–158

Interleaving in cellular systems, 123Intermediate frequency (IF)

heterodyne receivers, 160–162, 168–169low-IF receivers, 214–217zero second, 171–178

Intermodulation (IM)in cascades, 30–33GSM requirements, 134–135integer-N frequency synthesizers, 658overview, 21–25power amplifiers, 757between receiver blockers, 835

Intermodulation testsBluetooth, 146wideband CDMA, 142wireless standards, 131–132

Intersymbol interference (ISI), 101–104, 115–116Interwinding capacitance in inductors, 440–442,

461–463Inverse Laplace transform, 621Inverter delay, 614, 629IP2 (second intercept points), 188IP3 (third intercept points), 25–27IRR (image rejection ratio), 208–209, 212IRRs. See Image-reject receivers (IRRs)IS-95 CDMA, 137–139ISI (intersymbol interference), 101–104, 115–116ISM (industrial-scientific-medical) band, 130Isolation

LNAs, 260outphasing, 809reverse, 72

JJitter in divider design, 711

LL-section topologies, 67–68Laplace transform

charge pumps, 615–617PLL transient response, 621

Large-signal impedance matching, 780–782Latches

current-steering circuits, 686–689divide-by-2 circuits, 878–879

Latchup in mixers, 406–407Lateral-field capacitors, 529Lateral substrate currents, 452Layout parasitics in divide-by-2 circuit, 879LC oscillators

cross-coupled, 511–517LO swings, 366open-loop Q, 545–546phase noise, 501tuning ranges, 438, 498VCOs, 519, 571–575

Leakagedirect-conversion receivers, 179–184direct-conversion transmitters, 232–234heterodyne transmitters, 244LNA systems, 261mixers, 341–342, 357polar modulation, 802

Least mean square (LMS) algorithm, 234Leeson’s Equation, 547Lenz’s law, 452L’Hopital’s rule, 769Limit cycles in fractional-N synthesizers, 728Limiting stage in polar modulation, 794–795Line-to-line inductor spacing, 463Linear amplification with nonlinear components

(LINC), 802–803Linear drain capacitance, 780Linear model of oscillators, 548–549Linear power amplifiers, 110Linear systems, 9Linearity and linearization

LNAs, 260–261mixers, 338–339, 387–392nonlinearity. See Nonlinearitypower amplifiers, 756–758, 782–783

Cartesian feedback, 786–787Class A, 761–762envelope detector, 794envelope feedback, 788–790feedforward, 783–786predistortion, 787–788

LMS (least mean square) algorithm, 234LNAs. See Low-noise amplifiers (LNAs)LO. See Local oscillator (LO)Load capacitance

divide-by-2 circuits, 696oscillators, 498, 571

Load design for class E power amplifiers, 772Load inductors in divide-by-2 circuits, 696Load-pull tests, 781–782Load switching in LNAs, 311Local envelope feedback, 793Local oscillator (LO)

Page 46: Razavi Micro

Index 903

Cartesian feedback, 787coupling in power amplifiers, 760direct-conversion receivers, 179–184direct-conversion transmitters, 237–240drive capability, 499frequency synthesizers, 656–657, 660, 840heterodyne receivers, 160–164, 170–172, 176–177heterodyne transmitters, 244–246ideal waveforms, 349–350interface, 575–577leakage, 179–184, 341–342, 357LO-IF feedthrough, 340mixers

buffers, 413downconversion, 368, 374–387with high IP2, 398with low flicker noise, 407–408single-balanced and double-balanced, 348–350upconversion, 413–416

off-chip inductors, 430–431offset PLLs, 673on-off keying transceivers, 248–249outphasing mismatches, 805output waveforms, 501phase noise, 540–542polar modulation, 798ports

Miller dividers, 700, 703mixers, 337–338, 500

pulling, 846self-mixing, 181, 357swings, 366VCO phases, 746

Lock range in injection-locked dividers, 707–709Lock time in integer-N synthesizers, 658–659,

885–886Logic styles in divider design

current-steering circuits, 683–689divide-by-2 circuits, 689–697true single-phase clocking, 697–699

Loopsinteger-N synthesizers, 663, 881–886oscillator gain, 504–507phase-locked. See Phase-locked loops (PLLs)VCO phase gain, 601–602, 604VCO phase noise, 645–646

Lossesinductors, 444–455matching networks, 69–71microstrips, 480–482

Lossy circuits, noise in, 42, 56–58Lossy oscillatory systems, Q in, 459Lossy tanks in one-port oscillators, 509–510Low-frequency beat in active mixers, 402–403

Low-frequency components in phase noise, 569Low-IF receivers, 214–217

double-quadrature downconversion, 224–226polyphase filters, 217–224

Low-noise amplifiers (LNAs), 255band switching, 262, 312–314bandwidth, 261–263, 304common-gate stage. See Common-gate (CG) stage

in LNAscommon-source stage

with inductive degeneration, 284–296with inductive load, 266–269with resistive feedback, 269–272

design, 849–852gain, 257–258, 850–852gain switching, 305–312heterodyne receivers, 166, 169, 174–175high-IP2. See High-IP2 LNAsinput matching, 263–266input return loss, 258–259linearity, 260–261mixer design, 853, 856noise-cancelling, 300–303noise computations, 49–51noise figure, 255–257nonlinearity calculations, 325

degenerated common-source stage, 325–329degenerated differential pairs, 332–333differential and quasi-differential pairs, 331–332undegenerated common-source stage, 329–330

power dissipation, 263reactance-cancelling, 303–305stability, 259–260

Low-noise VCOs, 573–575Low-pass filters, 101

direct-conversion receivers, 179fractional-N synthesizers, 716image-reject receivers, 203, 206Miller dividers, 699–701, 705noise, 40PLLs, 603, 606polar modulation, 824–826power amplifier linearization, 790VCOs phase, 601, 875–876

Low-pass signals in direct-conversion receivers,189–190

Low-side injectionheterodyne receivers, 164–166image-reject receivers, 211–212

Lumped capacitanceinductors, 441, 462, 468–469interwinding, 462substrate, 453transformers, 472

Page 47: Razavi Micro

904 Index

Lumped modelinductors, 439, 455, 458MOS capacitors, 491MOS varactors, 487–489MOSFETs, 44

Lumped resistance of varactors, 487–488

MMagnetic coupling

along axis of symmetry, 465and coupling capacitance, 475eddy currents, 466plots, 433–434to substrate, 452–455, 457–459transformers, 470–472, 474

Make-before-break operations, 139MASH architecture, 732Matching networks, 62–63. See also Mismatches

losses, 69–71passive impedance transformation, 65–69,

752–753power amplifiers, 752–753, 814

high currents, 755large-signal, 780–782power combining, 821

Mathematical model for VCOs, 577–581MATLAB for power amplifiers, 757Memoryless systems, 12Metal losses in inductor modeling, 455Metal-plate capacitors, 493–495Metal resistance in inductor Q, 444–448Metastability in divider design, 711Microstrips, 479–482Microwave theory, 71Miller dividers, 699–702

with inductive load, 702–705moduli with, 705–707

Miller multiplication, 291–292Mirror symmetry in inductors, 464Mismatches

active mixers with high IP2, 400antenna/LNA interface, 258–259fractional-N synthesizers, 733–738I/Q

frequency planning, 848receivers, 194–199, 837–838transmitters, 229–232, 241, 244, 839–840

image-reject receivers, 209integer-N synthesizers, 883LNAs, 263–266multiphase frequency division, 746–747outphasing, 805passive upconversion mixers, 414PFD/CP, 627–630

PLL higher-order loops, 625polar modulation, 793–794quadrature oscillators, 588–590receivers, 837–838up and down current, 632–633, 637, 733–734

Mixers, 11, 337active. See Active mixersconsiderations, 337–338design, 851–856direct-conversion receivers, 187–189direct-conversion transmitters, 234–235,

240–243double-balanced. See Double-balanced mixersdownconversion. See Downconversion and

downconversion mixersas envelope detector, 789–790gain. See Conversion gainharmonic distortion, 15–16heterodyne receivers, 160–164, 168–170high-IP2 LNAs, 324injection-locked dividers, 708and LNA noise, 257Miller dividers, 699–704, 706noise and linearity, 338–339noise figures, 343–348oscillators. See Local oscillator (LO)passive. See Passive mixersperformance parameters, 338–343phase noise, 566PLLs, 672–673polar modulation, 826port-to-port feedthrough, 339–343single-balanced. See Single-balanced mixersupconversion. See Upconversion and upconversion

mixersMixing spurs, 338

direct-conversion receivers, 179, 199heterodyne receivers, 170–171heterodyne transmitters, 245–248

Mobile RF communications, 119antenna diversity, 122cellular systems, 119–120co-channel interference, 120delay spread, 122–123hand-offs, 120–121interleaving, 123path loss and multipath fading, 121–122

Mobile stations, 131Mobile telephone switching offices (MTSOs),

120–121Modeling

inductors, 455–460transformers, 475–476

Modems, 92

Page 48: Razavi Micro

Index 905

Modulation, 92–93AM. See Amplitude modulation (AM)analog, 93–99channel-length, 275, 633–634cross, 20–21, 140–141digital. See Digital modulationdirect-conversion receivers, 184FM, 95–96

frequency synthesizer spurs, 843–844heterodyne receivers, 173narrowband approximation, 96–98

image-reject receivers, 200intermodulation, 21–29phase, 95–99PLL-based, 667–673polar. See Polar modulation power amplifierswireless standards, 130

Modulation index, 93Modulus

dividers, 673–676, 705–707dual-modulus, 677–682, 880–881multi-modulus, 732prescaler, 682–683

fractional-N synthesizers, 718–721frequency multiplication, 610–611

MOS capacitors, 491–493MOS switches, 600MOS transistors, 43–46MOS varactors, 485–490, 519–520MTSOs (mobile telephone switching offices),

120–121Multi-carrier spectrum in OFDM, 117Multi-modulus dividers, 732Multipath fading, 121–123Multipath propagation, 115–116Multiphase frequency division, 745–748Multiple access techniques

CDMA, 126–130FDMA, 125TDMA, 125–126time and frequency division duplexing,

123–124Multiplexers (MUX)

fractional dividers, 742frequency planning, 846–847multiphase frequency division, 745–746VCOs, 877

Mutual injection pulling between oscillators, 589

NNAND gates

current-steering circuits, 683–684divide-by-2 circuits, 676divide-by-2/3 circuits, 680

phase/frequency detectors, 614single-phase clocking, 698

Narrowband FM approximation, 96–98Narrowband noise, 551Natural frequency

divide-by-2 circuits, 693oscillator mismatches, 588PLLs, 608

Near/far effect in CDMA, 129Negative feedback systems

noise-cancelling LNAs, 303oscillators, 502–503power amplifier linearization, 783VCO phase in PLLs, 601

Negative-Gm oscillators, 516Negative resistance

cross-coupled oscillators, 516LNA systems, 268one-port oscillators, 509–510

Nested feedforward architecture, 785908 phase shift

image-reject receivers, 200–205low-IF receivers, 215–216

NMOS devicestransconductance, 282transit frequency, 3VCO cross-coupled pairs, 530

Noise and noise figure (NF), 35–36AGC, 859bipolar transistors, 46cascaded stages, 52–56CDMA, 127direct-conversion receivers, 190–191, 346direct-conversion transmitters, 238flicker. See Flicker noisefractional-N synthesizers. See Fractional-N

synthesizers (FNSs)frequency planning, 846frequency synthesizers, 840–843FSK signals, 105–106IEEE802.11, 149input-referred, 46–48LNAs. See Low-noise amplifiers (LNAs)lossy circuits, 56–58mixers

with current-source helpers, 393–394in design, 853–854with high IP2, 399, 402linearity, 387–392noise figures, 343–348overview, 338–339qualitative analysis, 377–381quantitative analysis, 381–387RZ, 357–359

Page 49: Razavi Micro

906 Index

Noise and noise figure (NF) (Contd.)sampling, 359–364upconversion vs. downconversion, 409

modulus randomization, 718–721MOS transistors, 43–46offset PLLs, 670–671oscillators, 501, 503, 546–548overview, 48–52phase. See Phase noisepolar modulation, 802PSK signals, 105quadrature oscillators, 591–592quantization. See Quantization noiseas random process, 36–37receivers, 92, 834

direct-conversion, 191–194heterodyne, 169low-IF, 215

representation in circuits, 46–58resistors, 40–43and sensitivity, 59–60spectrum, 37–39transfer function, 39–40VCOs, 532, 871–875

Noise-cancelling LNAs, 300–303Noise floor, 59Non-delaying integrators, 728Non-return-to-zero (NRZ) mixers, 352Nonlinear power amplifiers, 93Nonlinear systems, 10, 75–77Nonlinearity

AM/PM conversion, 33–35cascaded stages, 29–33cross modulation, 20–21drain capacitance in impedance matching, 780gain compression, 16–20harmonic distortion, 14–16intermodulation, 21–29LNAs, 312, 325

degenerated common-source stage, 325–329degenerated differential pairs, 332–333differential and quasi-differential pairs, 331–332undegenerated common-source stage, 329–330

noise relationship to, 387–388overview, 12–14PFD/CP, 735–736receivers, 834–835Volterra series currents, 81–85

Nonmonotonic error, 736NOR gates

current-steering circuits, 683–684, 689dual-modulus dividers, 677–679synthesizer design, 883

Norton noise equivalent, 40, 548–549

NRZ (non-return-to-zero) mixers, 352Number of turns factor

metal resistance inductors, 445–446spiral inductors, 432–434, 436–437, 441–442transformers, 471, 473

OOctagonal inductors, 435Odd symmetry, 12, 15OFDM. See Orthogonal frequency division

multiplexing (OFDM)OFDM channelization in IEEE802.11, 147–148Off-chip devices

baluns, 323, 767, 810image-reject filters, 166inductors, 429–431

Offset frequencymixers, 853–855VCOs, 871, 874–876

Offset PLLs, 670–673Offset QPSK (OQPSK), 110Offsets

active mixers with high IP2, 398–400AGC, 859direct-conversion receivers, 181–187passive upconversion mixers, 414–415port-to-port feedthrough, 340–341

On-chip devicesac coupling, 183baluns, 323, 767high-pass filters, 214inductors, 179, 320–322, 694, 770low-pass filters, 179passive. See Passive devicestransformers, 299–300, 821, 826transmission lines, 829

On-off keying (OOK), 100, 248–2491–1 cascades, 7311-dB compression point, 17–181/f noise, 44–46One-port view of oscillators, 508–511, 584One-sided spectra, 38OOK (on-off keying), 100, 248–249Open-loop control

IS-95 CDMA, 138polar modulation, 793

Open-loop model of cross-coupled oscillators, 545,547–548

Open-loop modulation, 667Open-loop Q, 459, 544–545Opposite signs in sidebands, 97–98OQPSK (offset QPSK), 110OR gates

current-steering circuits, 684, 689

Page 50: Razavi Micro

Index 907

divide-by-2/3 circuits, 679divide-by-15/16 circuits, 681dual-modulus divider, 880

Orthogonal frequency division multiplexing (OFDM)average power, 235for delay spread, 147–148flicker noise, 854I/Q mismatch, 198overview, 115–118in transceiver design, 835, 837–838, 854

Orthogonal messages, 126Orthogonal phasors, 585Oscillators, 497

cross-coupled. See Cross-coupled oscillatorsdesign procedure, 571–575drive capability, 498–499feedback view, 502–508frequency range, 497–498integer-N synthesizer design, 881linear model, 548–549LO. See Local oscillator (LO)one-port view, 508–511, 584output voltage swing, 498performance parameters, 497–501phase/frequency detectors, 613phase noise. See Phase noisepulling in direct-conversion transmitters, 237–238Q in, 459, 545–570quadrature. See Quadrature oscillatorsthree-point, 517–518tuning ranges, 438, 498VCOs. See Voltage-controlled oscillators (VCOs)

Out-of-band blockingBluetooth, 146GSM, 133transceivers, 157–158wideband CDMA, 140

Out-of-band noise, 732–733Out-of-channel IP3, 835Outphasing power amplifiers

basics, 802–804design, 826–829issues, 805–810

Output capacitanceAM/PM conversion, 795, 799divide-by-2 circuits, 696mixers, 376power amplifiers, 819

Output impedancecommon-gate LNAs, 298current sources, 634–635large signals, 780–781matching networks, 69mixers, 357, 366

and noise, 48, 52, 54–56PLLs, 634power amplifiers, 809

Output matching networks, 69, 814Output power control, 820Output voltage swing, 9

flicker noise, 566mixers, 391, 423–424oscillators, 498power amplifiers, 756, 762, 778, 792, 816,

861–863VCOs, 531, 571–572

Output waveforms for RF oscillators, 501Overdrive voltage, 413Overlap for blind zones, 536Overlapping spectra

CDMA, 127–128IEEE802.11, 150

PPackages

coupling between pins, 430power amplifier parasitics, 755

Pad capacitance, 281, 286–287, 291–293PAE (power-added efficiency), 756Parallel inductors, 435Parallel-plate capacitors, 493–495, 529Parallel resistance

ideal capacitors, 63inductor modeling, 455–456

Parameters, scattering, 71–75Parasitics

active mixers, 396–397class E power amplifiers, 772cross-coupled oscillators, 514divide-by-2 circuits, 694, 879inductors, 439–444, 694LNAs, 260, 313parallel-plate capacitors, 494power amplifiers, 755, 765VCOs, 528–529, 535, 870

PARs (peak-to-average ratio) in OFDM, 117–118Partial channel selection, 168PAs. See Power amplifiers (PAs)Passband signals, 91–92Passive devices, 429

considerations, 429–431constant capacitors, 490–495inductors. See Inductance and inductorsmodeling issues, 431transformers. See Transformerstransmission lines. See Transmission lines (T-lines)varactors, 483–490

Passive filters, 158

Page 51: Razavi Micro

908 Index

Passive impedance transformation, 62–63matching networks, 65–71quality factor, 63series-to-parallel conversions, 63–65

Passive mixers, 350, 867carrier feedthrough, 413–416current-driven, 366–368gain, 350–357input impedance, 364–367LO self-mixing, 357Miller dividers, 704–705noise, 357–364upconversion, 409–413

Path loss, 121–122Patterned ground shields, 466PCS1900, 132PDs (phase detectors) in phase-locked loops,

597–600Peak detection, 790Peak-to-average ratio (PARs) in OFDM, 117–118Peak-to-peak voltage swing, 8–9Peak value, 18Peaking amplifiers, 811Performance

high-speed dividers, 690mixers, 338–343, 408–409oscillators, 497–501power amplifier linearization, 787trends, 2

Periodic impulse response, 559Periodic waveforms, low-pass filters with, 101Periods in phase noise, 536Perpendicular resultants in FM signals, 97PFDs. See Phase/frequency detectors (PFDs)Phase detectors (PDs) in PLLs, 597–600Phase-domain models for PLLs, 607Phase errors

GSM, 135PLLs, 600–601, 603–606, 608, 611, 615QPSK, 108

Phase feedback in polar modulation, 798–799Phase/frequency detectors (PFDs)

charge pump capacitive cascades, 615–618fractional-N synthesizers, 718, 734–737nonidealities, 627

channel-length modulation, 633–634charge injection and clock feedthrough,

630–632circuit techniques, 634–638up and down current mismatches, 632–633up and down skew and width mismatch,

627–630voltage compliance, 630

reset pulses, 737

Phase-locked loops (PLLs), 597charge-pump, 615–620continuous-time approximation, 622–623design, 646–647frequency multiplying CPPLLs, 623–625higher-order loops, 625–627in-loop modulation, 667–669loop bandwidth, 645–646offset, 670–673PFD/CP nonidealities. See Phase/frequency

detectors (PFDs)phase detectors, 597–600phase noise, 638–644polar modulation, 798, 800, 802, 825transient response, 620–622type-I. See Type-I PLLstype-II. See Type-II PLLs

Phase-locked phase noise profiles, 841Phase margin of PLLs, 625, 647–651Phase mismatches

direct-conversion receivers, 196direct-conversion transmitters, 241multiphase frequency division, 746–747

Phase modulation (PM)AM/PM conversion, 33–35overview, 95–99power amplifiers, 757tail noise, 567, 569–570

Phase modulation index, 95Phase noise

divider design, 709–712frequency planning, 846frequency synthesizers, 720–723, 732–733,

840–843offset PLLs, 672oscillators, 501, 536

additive noise conversions to, 550–552,554

basic concepts, 536–539bias current source, 565–570computation, 554–555current impulse, 557–558cyclostationary, 552–553, 565effects, 539–543flicker, 563–564higher harmonics, 564–565injected, 562–563linear model, 548–549noise shaping, 546–548Q, 544–546tail capacitance, 555–557time-variant systems, 559–561time-varying resistance, 553–554

Page 52: Razavi Micro

Index 909

reference, 643–644type-II PLLs, 638–644VCOs, 570–572, 638–643, 871–875

Phase shiftMiller dividers, 702offset PLLs, 673oscillators, 504–505, 507, 512, 591polar modulation, 794power amplifier linearization, 787

Phase shift keying (PSK)quadrature PSK, 107–112signal constellation, 105–106spectrum, 103waveforms, 100

Phasescharge pumps, 616phase/frequency detectors, 612polar modulation, 791, 802, 826QPSK, 109–110VCOs, 579, 581

Phasor diagrams, 550anti-phase coupling, 585–586in-phase coupling, 585quadrature oscillators, 587

Piecewise-linear waveforms, 383Planar transformers, 470, 473–474PLL-based modulation

in-loop modulation, 667–669offset PLLs, 670–673

PLLs. See Phase-locked loops (PLLs)PM (phase modulation)

AM/PM conversion, 33–35overview, 95–99power amplifiers, 757tail noise, 567, 569–570

PMOS deviceschannel-length modulation, 633charge pumps, 629cross-coupled pairs, 530–531dividers, 878LNAs, 271, 307, 310, 312mixers, 405, 422noise, 573, 852oscillators, 576, 592PLLs, 636surface states, 44

PN-junction varactors, 484–486Polar modulation power amplifiers, 790

basic idea, 790–793design, 824–826improved, 796–802issues, 793–796

Polyphase filters, 217–224Port-to-port feedthrough, 339–343

Ports, mixer, 337–338Positive feedback in oscillators, 504Positive-feedback power amplifiers, 819–821Power-added efficiency (PAE), 756Power amplifiers (PAs), 93, 755–756

cascode output stages, 751, 776–779class A, 760–764, 771–772class AB, 767class B, 764–767class C, 768–770class E, 772–775class F, 775–776considerations, 751–754design, 814–815, 861–864

cascode examples, 815–819common-mode stability, 866–867outphasing, 826–829polar modulation, 824–826positive-feedback, 819–821power combining, 821–824predrivers, 864–865

Doherty, 811–813efficiency, 755–756high currents, 754–755large-signal impedance matching, 780–782linearity. See Linearity and linearizationOFDM, 117outphasing

basic idea, 802–804design, 826–829issues, 805–810

polar modulation. See Polar modulation poweramplifiers

single-ended and differential, 758–760Power combining in power amplifiers, 821–824Power consumption trends, 2Power control

direct-conversion transmitters, 232–233DS-CDMA, 128–129IS-95 CDMA, 138polar modulation, 801power amplifiers, 820

Power conversion gain in mixers, 339Power dissipation

LNAs, 263oscillators, 501VCOs, 571

Power efficiency, 93Power gain, 7–9Power spectral density (PSD) noise, 37, 44–45Predistortion, 787–788Predrivers, 864–865, 867Prescaler modulus, 674–675, 682–683Primary inductances in power amplifiers, 765–767

Page 53: Razavi Micro

910 Index

Primary turns in transformers, 473–474Program counters in pulse swallow dividers,

674–675Programmable AGC gain, 859Propagation

mismatches, 625multipath, 115–116

PSD (power spectral density) noise, 37, 44–45Pseudo-random noise, 127PSK (phase shift keying)

quadrature PSK, 107–112signal constellation, 105–106spectrum, 103waveforms, 100

Pulse shaping, 103–104, 227Pulse-swallow counters, 880, 881Pulse-swallow dividers, 673–677Pulsewidth modulation, 386

QQ. See Quality factor (Q)QPSK (quadrature PSK) modulation, 107–112

EDGE, 136phase noise, 542–543

Quadrature amplitude modulation (QAM), 114–115Quadrature downconversion

heterodyne receivers, 174–175low-IF receivers, 219–221Weaver architecture, 213

Quadrature LO phases, 746Quadrature mismatches, 195Quadrature oscillators, 581

basic concepts, 581–584coupled oscillators, 584–589feedback model, 582–584improved, 589–592one-port model, 584simulation, 592–593

Quadrature phase separation, 216Quadrature PSK (QPSK) modulation, 107–112

EDGE, 136phase noise, 542–543

Quadrature upconverters, 227GMSK, 113heterodyne transmitters, 247–248I/Q mismatch, 230–231outputs, 422–424, 844passive mixers in, 411polar modulation, 797–798

Qualitative analysis of mixer noise, 377–381Quality factor (Q)

definitions, 459–460and frequency, 454inductors

differential, 463ground shields, 466–467metal resistance, 444–447T-line, 478, 480

passive impedance transformation, 63phase noise, 544–546polar modulation, 796quadrature oscillators, 588varactors, 484, 487, 489, 522–524VCOs, 534–535

Quantitative analysis of mixer noise, 381–387Quantization noise, 719–721

basic noise shaping, 722–728charge pump mismatch, 736–737DAC feedforward for, 738–742fractional dividers, 742–743higher-order noise shaping, 728–732multiphase frequency division, 745–748out-of-band, 732–733reference doubling, 743–745spectrum, 748–749

Quasi-differential pairsactive mixers with high IP2, 401–402active upconversion mixers, 416–417LNAs, 331–332

Quasi-static approximation, 757

RRadiation resistance, 42, 49–50Rail-to-rail operation

LO, 366, 577, 852–853, 867–868PLLs, 636TSCP, 697, 699VCOs, 877–878

Raised-cosine spectrum, 104Rake receivers, 138Random bit streams in low-pass filters, 101Random mismatches

fractional-N synthesizers, 737up and down current, 637

Random process, noise as, 36–37Randomization, modulus, 718–721Rapp model, 758, 838Ratioed logic, 878Rayleigh distribution, 122RC-CR networks

image-reject receivers, 203, 209–210low-IF receivers, 215–217

Reactance-cancelling LNAs, 303–305Receive bands, 157Receiver/demodulators, 92Receivers (RX), 848

AGC design, 856–861AGC range, 836–837

Page 54: Razavi Micro

Index 911

Bluetooth characteristics, 145–147direct-conversion. See Direct-conversion receiversfront ends, 156heterodyne. See Heterodyne receiversimage-reject. See Image-reject receivers (IRRs)input level range, 131LNA design, 849–852LNA leakage, 261low-IF, 214–217

double-quadrature downconversion, 224–226polyphase filters, 217–224

mixer design, 851–856noise, 92, 238, 834nonlinearity, 834–835sensitivity, 131simple view, 4–5system-level considerations, 834–838tolerance to blockers, 131wideband CDMA requirements, 140–143

Receiving antenna thermal noise, 42Reciprocal mixing

frequency synthesizers, 657–658, 840phase noise, 540

Reconstructed error in quantization noise, 738–739Reference cycles in fractional-N synthesizers,

716–718Reference doubling in quantization noise, 743–745Reference frequency in integer-N synthesizers, 656,

660, 664Reference phase noise in PLLs, 643–644Reference sidebands in integer-N synthesizers, 663Reflected waves, 71–73Regeneration mode current-steering circuits,

686–688Regulated cascodes, 634–635Regulator noise in oscillators, 501Replicas, IS-95 CDMA, 138Representation of noise, 46–58Reset pulses in phase/frequency detectors, 613Resettable D flipflops, 613Resistance and resistors

cross-coupled oscillators, 516ideal capacitors, 63inductor modeling, 455–456inductor Q, 444–448microstrips, 482noise in, 36, 40–43, 873–874one-port oscillators, 509–511power amplifier loads, 752–753radiation, 42, 49–50skin effect, 448–450T-lines, 477time-varying, 553–554varactors, 487–489

Resistance-free coupling with inductors, 470Resistive-feedback LNAs, 269–272, 849–851Resistive termination for LNAs, 264Resolution of ADCs, 837, 858–859Resonance frequency

inductor equations, 438VCOs, 519

Response decays in PLLs, 621Restoration force in phase noise, 544Retiming flipflops in integer-N synthesizers, 667Return paths in T-lines, 478Return-to-zero (RZ) mixers

noise, 357–359passive downconversion, 350passive upconversion, 410

Reverse channels, 119Reverse isolation, 72, 260RF chokes (RFC), 752RF design hexagon, 3RF-IF feedthrough, 341, 343RF-LO feedthrough, 341–343Ring oscillators

divide-by-2 circuits as, 690–691injection-locked, 709waveforms, 507

Ripplecharge pumps, 619, 632fractional-N synthesizers, 738integer-N synthesizers, 665, 883, 885–886PLLs, 603, 611, 625–627, 638power amplifiers, 759

Roaming in cellular systems, 120–121Roll-off factor, 104RZ (return-to-zero) mixers

noise, 357–359passive downconversion, 350passive upconversion, 410

SS (scattering) parameters, 71–75S/P (serial-to-parallel) converters, 107Sampling filters in fractional-N synthesizers, 665,

738Sampling mixers, 352–354

noise, 359–364passive upconversion, 409–410

Scattering (S) parameters, 71–75Second intercept points (IP2), 188Second-order 1-bit � modulators, 729Second-order nonlinearity, 29Second-order parallel tanks, Q in, 460Secondary images in image-reject receivers, 212Secondary inductances in power amplifiers, 765–767Secondary turns in transformers, 473–474

Page 55: Razavi Micro

912 Index

Self-corruptionasymmetric signals, 173–175direct-conversion receivers, 179, 190

Self-mixing LO, 181, 357Self-oscillation in divide-by-2 circuits, 691Self-resonance frequency of inductor capacitance,

442Sense mode for current-steering circuits, 686–687Sensitivity

overview, 59–60VCOs, 518wireless standards, 131

Sequence-asymmetric polyphase filters, 221Serial-to-parallel (S/P) converters, 107Series inductance in LNA common-source stage, 291Series inductors, 435Series peaking in divide-by-2 circuits, 694–696Series resistance

ideal capacitors, 63inductor modeling, 455–456

Series-to-parallel conversions, 63–65Servo amplifiers in PLLs, 636Settling behavior in integer-N synthesizers, 661–6647-cell reuse pattern, 120SFDR (spurious-free dynamic range), 60–62Shannon’s theorem, 155Shift-by-908 operation in image-reject receivers,

200–205Shot noise, 46Shunt peaking in divide-by-2 circuits, 694–695Shunt tail noise in low-noise VCOs, 573Sidebands

direct-conversion transmitters, 240–243fractional-N synthesizers, 716frequency-multiplying PLLs, 624heterodyne transmitters, 245integer-N synthesizers, 657, 663opposite signs in, 97–98VCO, 628

� modulatorsfractional-N synthesizers, 726–730, 733, 736–738VCO phases, 748

Signal cancellation loops, 783Signal constellations, 105–112Signal-to-noise ratio (SNR). See Noise and noise

figure (NF)Signs in sidebands, 97–98Simulators

integer-N synthesizers, 884–886power amplifiers, 757varactors, 487

Sinc pulses, 103–104Single-balanced mixers, 348–350

active, 369–370, 373

input impedance, 365noise, 362, 384passive, 351sampling, 355–356voltage conversion gain, 377

Single-ended power amplifiers, 758–760Single-ended stage in differential LNAs, 315–317Single-ended to differential LNA conversion,

320Single-sideband (SSB) mixing

direct-conversion transmitters, 240–243heterodyne transmitters, 247–248Miller dividers, 706noise figure, 344

Single-sideband (SSB) transmitters in image-rejectreceivers, 206

16QAM constellationdescription, 114phase noise, 543spectral regrowth, 118

64QAM constellation, 115Skin effect in inductors, 448–450, 457Sliding-IF receivers, 174–178Slope of I/O characteristic, 17SNR (signal-to-noise ratio). See Noise and noise

figure (NF)Soft hand-offs in IS-95 CDMA, 139Software-defined radios, 199Sonnet simulator, 439Source-bulk capacitance in LNA common-source

stage, 293Source impedance in noise figure, 50Source switching in charge pumps, 631Space diversity in cellular systems, 122Spectra

amplitude modulation, 94noise, 37–39overlapping, 127–128, 150

Spectral masks, 130–131Spectral regrowth, 118–119Spiral inductors

equations, 436–439geometries, 435high-IP2 LNAs, 323–324number of turns factor, 432–434, 436–437,

441–442overview, 431–434stacking, 467transformers, 471VCOs, 520–521

Split reset pulses, 737Spread spectrum (SS) communications, 127Spreading sequence code, 127Spurious-free dynamic range (SFDR), 60–62

Page 56: Razavi Micro

Index 913

Spurs, 338direct-conversion receivers, 179, 199fractional, 716frequency synthesizers, 843–844heterodyne receivers, 170–171heterodyne transmitters, 245–248integer-N synthesizers, 664–667

Square-wave LOs, 170SS (spread spectrum) communications, 127SSB (single-sideband) mixing

direct-conversion transmitters, 240–243heterodyne transmitters, 247–248Miller dividers, 706noise figure, 344

SSB (Single-sideband) transmitters in image-rejectreceivers, 206

StabilityLNAs, 259–260power amplifiers, 866–867

Stacked inductors, 467–470Stacked metal layers in microstrips, 482Stacked spirals

high-IP2 LNAs, 323–324transformers, 473–474

Stacked transformersdescription, 474–475power amplifiers, 821

Standards, wireless, 130–132Bluetooth, 143–147GSM, 132–137IEEE802.11a/b/g, 147–151IS-95 CDMA, 137–139wideband CDMA, 139–143

State diagrams for phase/frequency detectors, 612Static phase errors in PLLs, 603, 605Static systems, 12Step symmetry of inductors, 464Stern stability factor, 259Striplines, 483Subcarriers in OFDM, 117Substrate

capacitive coupling to, 439–440, 450–452,457–458

magnetic coupling to, 452–455, 457–459Superdyne system, 164Supply sensitivity of oscillators, 501Surface states, 44Swallow counters, 674–676, 682, 880, 881Switch on-resistance of VCOs, 535Switch parasitics in band switching LNAs, 313Switch transistors

class E power amplifiers, 772–773phase noise, 538VCOs, 534

Switchable stages in polar modulation, 824Switched capacitors for VCOs, 533, 872Switching pair current in active mixers, 405, 407Switching power amplifiers, 772–773Symbols in QPSK, 107Symmetric inductors, 435, 460–466, 520–521Symmetrically-modulated signals, 172Synchronous AM detectors, 790Synchronous operation of dual-modulus dividers,

680Synthesizers

fractional-N. See Fractional-N synthesizers(FNSs)

integer-N. See Integer-N synthesizersPLLs, 611

System-level design considerations, 833frequency planning, 844–848frequency synthesizers, 840–844receivers, 834–838transmitters, 838–840

System specifications for oscillators, 497

TT-lines (transmission lines), 476–478

coplanar, 482–483microstrips, 479–482striplines, 483

Tail capacitanceflicker noise, 387, 405phase noise, 555–557

Tail currentcross-coupled oscillators, 513–515passive upconversion mixers, 412phase noise, 556time-varying resistance, 554VCOs, 525–526, 531–532, 874–875

Tail noisecross-coupled oscillators, 513, 565–566low-noise VCOs, 573, 575phase noise, 565–570, 708

Tails coupling in quadrature oscillators, 589Tapered stages in power amplifiers, 754TDD (time division duplexing), 123–124TDMA (time-division multiple access), 125–126Temperature. See Thermal noiseTerminals in mobile RF communications, 119Terminating resistors in LNAs, 264Thermal noise, 36

direct-conversion receivers, 191MOS transistors, 43–46phase, 566, 568resistors, 40–43

Thevenin equivalent of divide-by-2 circuits, 695Thevenin model of resistor thermal noise, 40, 57

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914 Index

Third intercept points (IP3), 25–27Third-order characteristic, 13Third-order intermodulation, 22, 31Three-point oscillators, 517–518Time constants in PLL transient response, 621Time-contracted simulation of integer-N synthesizer

loops, 884Time diversity

cellular systems, 122IS-95 CDMA, 138

Time division duplexing (TDD), 123–124Time-division multiple access (TDMA), 125–126Time-variant systems

overview, 9–12passive downconversion mixers, 366phase noise, 559–561

Time-varying resistance in phase noise, 553–554Time-varying voltage division in outphasing, 808Timing errors in class E power amplifiers, 773Tones

fractional-N synthesizers, 727–728power amplifiers, 756–757

Top-biased VCOs, 525–526Top current in phase noise, 568–569Total frequency, 95Total noise power in phase noise, 541Total phase

modulation, 95VCOs, 579

Total stored energy in inductor capacitance, 441Track-mode noise, 359–361Tradeoffs in design, 3Transceivers, 92, 119, 155

channel selection and band selection, 157–159considerations, 155–157design example, 833

integer-N synthesizers, 869–886receivers, 848–861system-level design. See System-level design

considerationstransmitters, 861–869

on-off keying, 248–249receivers. See Receivers (RX)transmitters. See Transmitters (TX)TX-RX feedthrough, 159–160

TransconductanceLNAs

common-gate stage, 279–280, 282common-source stage, 288–291differential, 319gain switching, 306

mixers, 368, 394–397, 407oscillators, 511quadrature oscillators, 591

time-varying resistance, 554VCOs, 875

Transfer functionsfractional-N synthesizers, 722, 724, 728, 732–733integer-N synthesizers, 661–662, 665–666, 669,

693–696, 709integrators, 506LNAs, 277–278, 303noise, 39–41, 544, 569, 638–641, 643oscillators, 544, 547–548, 562PLLs, 606–608, 615, 617–620, 622–623, 649RC-CR networks, 203transformers, 472, 475

Transformation, passive impedance, 62–63matching networks, 65–71quality factor, 63series-to-parallel conversions, 63–65

Transformers, 470coupling capacitance, 474–475impedance transforms, 69modeling, 475–476outphasing, 806–807power amplifiers, 753, 767, 821–824structures, 470–475

Transient response in type-II PLLs, 620–622Transistors

class E power amplifiers, 772–773cross-coupled oscillators, 514phase noise, 538thermal noise, 43–46VCOs, 534

Transmission lines (T-lines), 476–478coplanar, 482–483microstrips, 479–482striplines, 483

Transmission masks in IEEE802.11, 147–148Transmit bands, 158–159Transmit spectrum masks, 144–145Transmitted noise in offset PLLs, 670–671Transmitter antenna thermal noise, 42Transmitters (TX), 861

Bluetooth characteristics, 143–145cell phones, 91considerations, 226–227direct-conversion. See Direct-conversion

transmittersGSM specifications, 135–136harmonic distortion, 16heterodyne, 244–248LNA leakage, 261outphasing, 804power amplifiers, 861–867in simple view, 4–5system-level considerations, 838–840

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Index 915

upconverters, 867–869wideband CDMA, 139–140wireless standards, 130–131wireless systems, 156

Trends, 2–3True single-phase clocking (TSPC), 697–699Tuned amplifiers, 444, 512Tuning VCOs, 521–522

amplitude variation with frequency tuning, 532continuous, 524–532discrete, 532–536range limitations, 521–522

Turn-to-turn capacitances in inductors, 441–442Two-level modulation schemes, 92Two-pole oscillators, 504–505Two-sided spectra, 38Two-tone tests

active downconversion mixers, 392intermodulation, 22, 24–25, 28power amplifiers, 756–757sensitivity, 61–62

TX-RX feedthrough, 159–160Type-I PLLs

drawbacks, 611frequency multiplication, 609–611loop dynamics, 606–609simple circuit, 601–606VCO phase alignment, 600–601

Type-II PLLs, 611–612charge pumps, 614–620continuous-time approximation limitations,

622–623design procedure, 646–647frequency-multiplying CPPLLs, 623–625higher-order loops, 625–627loop bandwidth, 645–646PFD/CP nonidealities. See Phase/frequency

detectors (PFDs)phase/frequency detectors, 612–614phase margin, 647–651phase noise, 638–644transient response, 620–622

UUndegenerated common-source stages, LNA

nonlinearity calculations for, 329–330Uniformly-distributed model of inductor capacitance,

441–442Unilateral coupling in quadrature oscillators, 581Units, 7–9Unity-gain voltage buffers, 602, 607Up currents and pulses

charge pumps, 614–615, 630–633, 645–647fractional-N synthesizers, 733–734

integer-N synthesizers, 883PLL higher-order loops, 625, 627quantization noise, 739

Up skew in PFD/CP, 627–630Upconversion and upconversion mixers, 339, 408

active, 416–424design, 867–869heterodyne transmitters, 244–248I/Q mismatch, 229–232linearity, 234–235offset PLLs, 671output spectrum, 844passive, 409–416performance requirements, 408–409polar modulation, 797–798power amplifiers, 758quadrature, 113, 227, 230–231scaling up, 230–231

Uplinks, 119

VV/I (voltage-to-current) conversion

downconversion, 368–369upconversion, 867–868

Varactorsoverview, 483–490Q, 522–524VCOs, 519–520, 571, 870

Variable coding rates in IS-95 CDMA, 139Variable-delay stages in integer-N synthesizers,

665–667Variable-envelope signals in QPSK, 110Variable-gain amplifiers (VGAs), 860Variance, time. See Time-variant systemsVCOs. See Voltage-controlled oscillators (VCOs)Vector modulators, 227VGAs (variable-gain amplifiers), 860Vn1 and Vn2 spectrum in mixers, 360–364Voice signals, 91Voltage compliance issues in PFD/CP, 630Voltage-controlled oscillators (VCOs), 485

Bluetooth, 144divider design, 673–674, 692figure of merit, 570–571fractional-N synthesizers, 716, 723free-running, 655frequency multiplication, 610FSK, 112integer-N synthesizers, 656, 666, 869–877low-noise, 573–575mathematical model, 577–581multiphase frequency division, 745–748overview, 518–521phase noise, 638–643, 711–712

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916 Index

Voltage-controlled oscillators (VCOs) (Contd.)PLLs, 603–606

offset, 672–673phase alignment, 600–601PLL-based modulation, 667–668

polar modulation, 797–798transceiver design, 842, 845–847tuning, 521–522

amplitude variation with frequency tuning, 532continuous, 524–532discrete, 532–536range limitations, 521–522

varactor Q, 522–524Voltage-dependent capacitors, 483–490Voltage gain, 7–9

conversion. See Conversion gainLNA common-gate stage, 276

Voltage swings, 9flicker noise, 566mixers, 391, 423–424oscillators, 498, 515power amplifiers, 756, 762, 778, 792, 816,

861–863VCOs, 531, 571–572

Voltage-to-current (V/I) conversiondownconversion, 368–369upconversion, 867–868

Voltage-voltage feedback in common-gate LNAs,296

Volterra seriesnonlinear currents, 81–85overview, 77–81

WWalsh code, 127Weaver receivers, 210–213

White noise, 563–564, 642Wideband CDMA, 139–143Width mismatches in PFD/CP, 627–630Wilkinson combiners, 827–829Wilkinson dividers, 828Wire capacitance and inductors, 441Wire resistance and inductors, 444–448Wireless communication overview, 1–3

big picture, 4–5RF challenges, 3–4

Wireless standards, 130–132Bluetooth, 143–147GSM, 132–137IEEE802.11a/b/g, 147–151IS-95 CDMA, 137–139wideband CDMA, 139–143

Wiresbond. See Bond wirestransmission lines. See Transmission lines (T-lines)

XXNOR (exclusive-NOR) gates, 152XOR (exclusive-OR) gates

current-steering circuits, 685–686phase detectors, 598–599PLLs, 603reference doubling, 743

ZZero crossings

Miller dividers, 701–702mixer flicker noise, 385–386, 407–408phase-modulated signals, 95phase noise, 536–538, 557–558

Zero-IF architecture, 179Zero second IFs in heterodyne receivers, 171–174