Quad, 8-Bit, 100 MSPS, Serial LVDS 1.8 V ADC Data Sheet AD9287

Quad, 8-Bit, 100 MSPS,Serial LVDS 1.8 V ADC

Data Sheet AD9287

Rev. G Document Feedback Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.Tel: 781.329.4700 ©2006–2020 Analog Devices, Inc. All rights reserved. Technical Support www.analog.com

FEATURES 4 ADCs integrated into 1 package 133 mW ADC power per channel at 100 MSPS SNR = 49 dB (to Nyquist) ENOB = 7.85 bits SFDR = 65 dBc (to Nyquist) Excellent linearity

DNL = ±0.2 LSB (typical) INL = ±0.2 LSB (typical)

Serial LVDS (ANSI-644, default) Low power, reduced signal option (similar to IEEE 1596.3)

Data and frame clock outputs 295 MHz full-power analog bandwidth 2 V p-p input voltage range 1.8 V supply operation Serial port control

Full-chip and individual-channel power-down modes Flexible bit orientation Built-in and custom digital test pattern generation Programmable clock and data alignment Programmable output resolution Standby mode

APPLICATIONS Medical imaging and nondestructive ultrasound Portable ultrasound and digital beam-forming systems Quadrature radio receivers Diversity radio receivers Tape drives Optical networking Test equipment

GENERAL DESCRIPTION

The AD9287 is a quad, 8-bit, 100 MSPS analog-to-digital con-verter (ADC) with an on-chip sample-and-hold circuit designed for low cost, low power, small size, and ease of use. The product operates at a conversion rate of up to 100 MSPS and is optimized for outstanding dynamic performance and low power in applications where a small package size is critical.

The ADC requires a single 1.8 V power supply and LVPECL-/ CMOS-/LVDS-compatible sample rate clock for full performance operation. No external reference or driver components are required for many applications.

The ADC automatically multiplies the sample rate clock for the appropriate LVDS serial data rate. A data clock output (DCO) for

FUNCTIONAL BLOCK DIAGRAM

SERIALLVDS

REFSELECT

+–

AD9287

AGND

VIN – A

VIN + A

VIN – B

VIN + B

VIN – D

VIN + D

VIN – C

VIN + C

SENSE

VREF

AVDD DRVDD

8

8

8

8

PDWN

REFTREFB

D – AD + A

D – BD + B

D – DD + D

D – CD + C

FCO–

FCO+

DCO+DCO–

CLK+

DRGND

CLK–

SERIAL PORTINTERFACE

CSB SCLK/DTPSDIO/ODMRBIAS

SERIALLVDS

SERIALLVDS

SERIALLVDS

PIPELINEADC

PIPELINEADC

PIPELINEADC

PIPELINEADC

DATA RATEMULTIPLIER

0.5V

059

66-0

01

T/H

T/H

T/H

T/H

Figure 1.

capturing data on the output and a frame clock output (FCO) for signaling a new output byte are provided. Individual-channel power-down is supported and typically consumes less than 2 mW when all channels are disabled.

The ADC contains several features designed to maximize flexibility and minimize system cost, such as programmable clock and data alignment and programmable digital test pattern generation. The available digital test patterns include built-in deterministic and pseudorandom patterns, along with custom user-defined test patterns entered via the serial port interface (SPI).

The AD9287 is available in an RoHS compliant, 48-lead LFCSP. It is specified over the industrial temperature range of −40°C to +85°C.

PRODUCT HIGHLIGHTS

1. Small Footprint. Four ADCs are contained in a small, space-saving package.

2. Low power of 133 mW/channel at 100 MSPS. 3. Ease of Use. A data clock output (DCO) is provided that

operates at frequencies of up to 400 MHz and supports double data rate (DDR) operation.

4. User Flexibility. The SPI control offers a wide range of flexible features to meet specific system requirements.

5. Pin-Compatible Family. This includes the AD9219 (10-bit), AD9228 (12-bit), and AD9259 (14-bit).

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AD9287 Data Sheet

Rev. G | Page 2 of 51

TABLE OF CONTENTS Features .............................................................................................. 1

Applications ...................................................................................... 1

General Description ......................................................................... 1

Functional Block Diagram .............................................................. 1

Product Highlights ........................................................................... 1

Revision History ............................................................................... 3

Specifications .................................................................................... 4

AC Specifications ......................................................................... 5

Digital Specifications ................................................................... 6

Switching Specifications .............................................................. 7

Timing Diagrams .............................................................................. 8

Absolute Maximum Ratings ......................................................... 10

Thermal Impedance ................................................................... 10

ESD Caution................................................................................ 10

Pin Configuration and Function Descriptions .......................... 11

Equivalent Circuits ......................................................................... 13

Typical Performance Characteristics ........................................... 15

Theory of Operation ...................................................................... 19

Analog Input Considerations ................................................... 19

Clock Input Considerations ..................................................... 21

Serial Port Interface (SPI) ............................................................. 29

Hardware Interface .................................................................... 29

Memory Map .................................................................................. 31

Reading the Memory Map Table ............................................. 31

Reserved Locations .................................................................... 31

Default Values ............................................................................ 31

Logic Levels ................................................................................. 31

Evaluation Board ............................................................................ 35

Power Supplies ........................................................................... 35

Input Signals ............................................................................... 35

Output Signals ............................................................................ 35

Default Operation and Jumper Selection Settings ................ 36

Alternative Analog Input Drive Configuration ..................... 37

Outline Dimensions ....................................................................... 51

Ordering Guide .......................................................................... 51

Data Sheet AD9287


REVISION HISTORY

11/2020—Rev. F to Rev. G Changed CP-48-8 to CP-48-9 ..................................... Throughout Changes to Figure 5 ........................................................................ 11 Updated Outline Dimensions ....................................................... 51 Changes to Ordering Guide ........................................................... 51 1/2015—Rev. E to Rev. F Changes to Figure 2 .......................................................................... 8 Changes to Figure 4 .......................................................................... 9 12/2011—Rev. D to Rev. E Changes to Output Signals Section and Figure 60 ..................... 35 Change to Default Operation and Jumper Selection Settings Section ............................................................................................... 36 Changes to Figure 63 ...................................................................... 39 Added Endnote 2 in Ordering Guide ........................................... 51 4/2010—Rev. C to Rev. D Changes to Table 16 ........................................................................ 33 Updated Outline Dimensions ....................................................... 51 Changes to Ordering Guide ........................................................... 51 1/2010—Rev. B to Rev. C Updated Outline Dimensions ....................................................... 51 Changes to Ordering Guide ........................................................... 52 7/2007—Rev. A to Rev. B Changes to Figure 2 and Figure 4 ................................................... 7 Changes to Table 17 ........................................................................ 48

5/2007—Rev. 0 to Rev. A Changes to Logic Output (SDIO/ODM) ....................................... 5 Change to Pipeline Latency ............................................................. 6 Added Endnote 2 to Table 4 ............................................................ 6 Changes to Figure 2 to Figure 4 ...................................................... 7 Changes to Figure 10 ...................................................................... 12 Change to Figure 15 Caption ........................................................ 14 Changes to Figure 29 ...................................................................... 16 Changes to Figure 41 ...................................................................... 19 Changes to Clock Duty Cycle Considerations Section .............. 20 Changes to Power Dissipation and Power-Down Mode Section .. 21 Changes to Figure 50 to Figure 52 Captions ............................... 23 Change to Table 8 ........................................................................... 23 Changes to Table 9 Endnote .......................................................... 24 Changes to Digital Outputs and Timing Section ....................... 25 Added Table 10 ............................................................................... 25 Changes to RBIAS Pin Section ...................................................... 26 Deleted Figure 53 and Figure 54 ................................................... 26 Changes to Figure 56 ...................................................................... 27 Changes to Hardware Interface Section ...................................... 28 Added Figure 57 .............................................................................. 29 Changes to Table 15 ........................................................................ 29 Changes to Reading the Memory Map Table Section ............... 30 Changes to Output Signals Section .............................................. 34 Changes to Figure 60 ...................................................................... 34 Changes to Default Operation and Jumper Selection Settings Section ................................................ 35 Changes to Alternative Analog Input Drive Configuration Section .................................................................... 36 Changes to Figure 63 ...................................................................... 38 Changes to Table 17 ........................................................................ 46 Changes to Ordering Guide .......................................................... 50 7/2006—Revision 0: Initial Version

AD9287 Data Sheet


SPECIFICATIONS AVDD = 1.8 V, DRVDD = 1.8 V, 2 V p-p differential input, 1.0 V internal reference, AIN = −0.5 dBFS, unless otherwise noted.

Table 1. Parameter1 Temp Min Typ Max Unit RESOLUTION 8 Bits ACCURACY

No Missing Codes Full Guaranteed Offset Error Full ±5 ±23.4 mV Offset Matching Full ±5 ±23.4 mV Gain Error Full ±6 % FS Gain Matching Full ±0.5 ±2 % FS Differential Nonlinearity (DNL) Full ±0.2 ±0.8 LSB Integral Nonlinearity (INL) Full ±0.2 ±0.65 LSB

TEMPERATURE DRIFT Offset Error Full ±2 ppm/°C Gain Error Full ±17 ppm/°C Reference Voltage (1 V Mode) Full ±21 ppm/°C

REFERENCE Output Voltage Error (VREF = 1 V) Full ±5 ±30 mV Load Regulation at 1.0 mA (VREF = 1 V) Full 3 mV Input Resistance Full 6 kΩ

ANALOG INPUTS Differential Input Voltage (VREF = 1 V) Full 2 V p-p Common-Mode Voltage Full AVDD/2 V Differential Input Capacitance Full 7 pF Analog Bandwidth, Full Power Full 295 MHz

POWER SUPPLY AVDD Full 1.7 1.8 1.9 V DRVDD Full 1.7 1.8 1.9 V IAVDD Full 260 274 mA IDRVDD Full 34.5 38 mA Total Power Dissipation (Including Output Drivers) Full 530 562 mW Power-Down Dissipation Full 2 4 mW Standby Dissipation2 Full 72 mW

CROSSTALK Full −100 dB CROSSTALK (Overrange Condition)3 Full −100 dB 1 See the AN-835 Application Note, Understanding High Speed ADC Testing and Evaluation, at www.analog.com for definitions and for details on how these tests were

completed. 2 Can be controlled via the SPI. 3 Overrange condition is specific with 6 dB of the full-scale input range.

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Data Sheet AD9287


AC SPECIFICATIONS AVDD = 1.8 V, DRVDD = 1.8 V, 2 V p-p differential input, 1.0 V internal reference, AIN = −0.5 dBFS, unless otherwise noted.

Table 2. Parameter1 Temp Min Typ Max Unit SIGNAL-TO-NOISE RATIO (SNR)

fIN = 2.4 MHz Full 49.2 dB fIN = 49.7 MHz Full 46.5 49.0 dB fIN = 70 MHz Full 49.0 dB

SIGNAL-TO-NOISE AND DISTORTION RATIO (SINAD) fIN = 2.4 MHz Full 49.0 dB fIN = 49.7 MHz Full 46.0 48.5 dB fIN = 70 MHz Full 48.5 dB

EFFECTIVE NUMBER OF BITS (ENOB) fIN = 2.4 MHz Full 7.88 Bits fIN = 49.7 MHz Full 7.43 7.85 Bits fIN = 70 MHz Full 7.85 Bits

SPURIOUS-FREE DYNAMIC RANGE (SFDR) fIN = 2.4 MHz Full 70.0 dBc fIN = 49.7 MHz Full 54.0 65.0 dBc fIN = 70 MHz Full 62.0 dBc

WORST HARMONIC (Second or Third) fIN = 2.4 MHz Full −70.0 dBc fIN = 49.7 MHz Full −65.0 −54.0 dBc fIN = 70 MHz Full −62.0 dBc

WORST OTHER (Excluding Second or Third) fIN = 2.4 MHz Full −77.0 dBc fIN = 49.7 MHz Full −74.0 −58.5 dBc fIN = 70 MHz Full −71.0 dBc

TWO-TONE INTERMODULATION DISTORTION (IMD)— AIN1 AND AIN2 = −7.0 dBFS

fIN1 = 15 MHz, fIN2 = 16 MHz 25°C 70.0 dBc fIN1 = 70 MHz, fIN2 = 71 MHz 25°C 68.5 dBc

1 See the AN-835 Application Note, Understanding High Speed ADC Testing and Evaluation, at www.analog.com for definitions and for details on how these tests were

completed.



AD9287 Data Sheet


DIGITAL SPECIFICATIONS AVDD = 1.8 V, DRVDD = 1.8 V, 2 V p-p differential input, 1.0 V internal reference, AIN = −0.5 dBFS, unless otherwise noted.

Table 3. Parameter1 Temp Min Typ Max Unit CLOCK INPUTS (CLK+, CLK−)

Logic Compliance CMOS/LVDS/LVPECL Differential Input Voltage2 Full 250 mV p-p Input Common-Mode Voltage Full 1.2 V Input Resistance (Differential) 25°C 20 kΩ Input Capacitance 25°C 1.5 pF

LOGIC INPUTS (PDWN, SCLK/DTP) Logic 1 Voltage Full 1.2 3.6 V Logic 0 Voltage Full 0.3 V Input Resistance 25°C 30 kΩ Input Capacitance 25°C 0.5 pF

LOGIC INPUT (CSB) Logic 1 Voltage Full 1.2 3.6 V Logic 0 Voltage Full 0.3 V Input Resistance 25°C 70 kΩ Input Capacitance 25°C 0.5 pF

LOGIC INPUT (SDIO/ODM) Logic 1 Voltage Full 1.2 DRVDD + 0.3 V Logic 0 Voltage Full 0 0.3 V Input Resistance 25°C 30 kΩ Input Capacitance 25°C 2 pF

LOGIC OUTPUT (SDIO/ODM)3 Logic 1 Voltage (IOH = 800 μA) Full 1.79 V Logic 0 Voltage (IOL = 50 μA) Full 0.05 V

DIGITAL OUTPUTS (D + x, D − x), (ANSI-644) Logic Compliance LVDS Differential Output Voltage (VOD) Full 247 454 mV Output Offset Voltage (VOS) Full 1.125 1.375 V Output Coding (Default) Offset binary

DIGITAL OUTPUTS (D + x, D − x), (Low Power, Reduced Signal Option)

Logic Compliance LVDS Differential Output Voltage (VOD) Full 150 250 mV Output Offset Voltage (VOS) Full 1.10 1.30 V Output Coding (Default) Offset binary


completed. 2 This is specified for LVDS and LVPECL only. 3 This is specified for 13 SDIO pins sharing the same connection.



Data Sheet AD9287


SWITCHING SPECIFICATIONS AVDD = 1.8 V, DRVDD = 1.8 V, 2 V p-p differential input, 1.0 V internal reference, AIN = −0.5 dBFS, unless otherwise noted.

Table 4. Parameter1, 2 Temp Min Typ Max Unit CLOCK3

Maximum Clock Rate Full 100 MSPS Minimum Clock Rate Full 10 MSPS Clock Pulse Width High (tEH) Full 5 ns Clock Pulse Width Low (tEL) Full 5 ns

OUTPUT PARAMETERS3 Propagation Delay (tPD) Full 2.0 2.7 3.5 ns Rise Time (tR) (20% to 80%) Full 300 ps Fall Time (tF) (20% to 80%) Full 300 ps FCO Propagation Delay (tFCO) Full 2.0 2.7 3.5 ns DCO Propagation Delay (tCPD)4 Full tFCO +

(tSAMPLE/16) ns

DCO to Data Delay (tDATA)4 Full (tSAMPLE/16) − 300 (tSAMPLE/16) (tSAMPLE/16) + 300 ps DCO to FCO Delay (tFRAME)4 Full (tSAMPLE/16) − 300 (tSAMPLE/16) (tSAMPLE/16) + 300 ps Data to Data Skew (tDATA-MAX − tDATA-MIN)

Full ±50 ±150 ps

Wake-Up Time (Standby) 25°C 600 ns Wake-Up Time (Power-Down) 25°C 375 μs Pipeline Latency Full 8 CLK cycles

APERTURE Aperture Delay (tA) 25°C 500 ps Aperture Uncertainty (Jitter) 25°C <1 ps rms Out-of-Range Recovery Time 25°C 2 CLK cycles


completed. 2 Measured on standard FR-4 material. 3 Can be adjusted via the SPI. 4 tSAMPLE/16 is based on the number of bits multiplied by 2; delays are based on half duty cycles.



AD9287 Data Sheet


TIMING DIAGRAMS

DCO+

DCO–

CLK+

FCO–

FCO+

D – x

D + x

CLK–

MSBN – 9

D5N – 9

tDATA

tFRAMEtFCO

tPD

D4N – 9

D6N – 9

D1N – 8

D3N – 9

D5N – 8

D4N – 8

D6N – 8

D3N – 8

D2N – 8

D1N – 9

MSBN – 8

D0N – 9

D2N – 9

tCPD

tEH tEL

059

66-0

40

VIN ± x

N – 1

N

tA

Figure 2. 8-Bit Data Serial Stream, MSB First (Default)

DCO–

DCO+

D – x

D + x

FCO–

FCO+

VIN ± x

CLK–

CLK+

MSBN – 9

D10N – 9

D9N – 9

D8N – 9

D7N – 9

D6N – 9

D5N – 9

D4N – 9

D3N – 9

0

D2N – 9

0

D1N – 9

0

D0N – 9

0

D10N – 8

MSBN – 8

N – 1

N

tDATA

tFRAMEtFCO

tPD

tCPD

tEH

tA

tEL

059

66-0

39

Figure 3. 12-Bit Data Serial Stream, MSB First

Data Sheet AD9287


DCO–

DCO+

D – x

D + x

FCO+

FCO–

VIN ± x

CLK–

CLK+

LSBN – 9

D0N – 9

D1N – 9

D2N – 9

D3N – 9

D4N – 9

D5N – 9

D6N – 9

N – 1

tA

N

tDATA

tFRAMEtFCO

tPD

tCPD

tEH tEL

05

966

-04

1

LSBN – 8

D0N – 8

D1N – 8

D2N – 8

D3N – 8

D4N – 8

Figure 4. 8-Bit Data Serial Stream, LSB First

AD9287 Data Sheet


ABSOLUTE MAXIMUM RATINGS Table 5.

Parameter With Respect To Rating

ELECTRICAL AVDD AGND −0.3 V to +2.0 V DRVDD DRGND −0.3 V to +2.0 V AGND DRGND −0.3 V to +0.3 V AVDD DRVDD −2.0 V to +2.0 V Digital Outputs

(D + x, D − x, DCO+, DCO−, FCO+, FCO−)

DRGND −0.3 V to +2.0 V

CLK+, CLK− AGND −0.3 V to +3.9 V VIN + x, VIN − x AGND −0.3 V to +2.0 V SDIO/ODM AGND −0.3 V to +2.0 V PDWN, SCLK/DTP, CSB AGND −0.3 V to +3.9 V REFT, REFB, RBIAS AGND −0.3 V to +2.0 V VREF, SENSE AGND −0.3 V to +2.0 V

ENVIRONMENTAL Operating Temperature

Range (Ambient) −40°C to +85°C

Maximum Junction Temperature

150°C

Lead Temperature (Soldering, 10 sec)

300°C

Storage Temperature Range (Ambient)

−65°C to +150°C

Stresses at or above those listed under Absolute Maximum Ratings may cause permanent damage to the product. This is a stress rating only; functional operation of the product at these or any other conditions above those indicated in the operational section of this specification is not implied. Operation beyond the maximum operating conditions for extended periods may affect product reliability.

THERMAL IMPEDANCE

Table 6. Air Flow Velocity (m/sec) θJA

1 θJB θJC Unit 0.0 24 °C/W 1.0 21 12.6 1.2 °C/W 2.5 19 °C/W 1 θJA for a 4-layer PCB with solid ground plane (simulated). Exposed pad

soldered to PCB.

ESD CAUTION

Data Sheet AD9287


PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

059

66

-00

3

NOTES1. THE EXPOSED PAD MUST BE CONNECTED TO ANALOG GROUND.

123

AVDDAVDDVIN – A

4 VIN + A5 AVDD6 PDWN7 CSB

24D

CO

+23

DC

O–

22F

CO

+21

FC

O–

20D

+ A

19D

– A

18D

+ B

17D

– B

16D

+ C

15D

– C

14D

+ D

13D

– D

44R

EF

T45

AV

DD

46A

VD

D47

VIN

+ C

48V

IN –

C

43R

EF

B42

VR

EF

41S

EN

SE

40R

BIA

S39

AV

DD

38V

IN +

B37

VIN

– B

AD9287TOP VIEW

(Not to Scale)

25DRVDD26DRGND27AVDD28AVDD29CLK+30CLK–31AVDD32AVDD33VIN + D34VIN – D35AVDD36AVDD

8 SDIO/ODM9 SCLK/DTP

10 AVDD11 DRGND12 DRVDD

Figure 5. 48-Lead LFCSP Pin Configuration, Top View

Table 7. Pin Function Descriptions Pin No. Mnemonic Description 0 AGND Analog Ground (Exposed Paddle) 1, 2, 5, 6, 9, 10, 27, 32, 35, 36, 39, 45, 46

AVDD 1.8 V Analog Supply

11, 26 DRGND Digital Output Driver Ground 12, 25 DRVDD 1.8 V Digital Output Driver Supply 3 VIN − D ADC D Analog Input Complement 4 VIN + D ADC D Analog Input True 7 CLK− Input Clock Complement 8 CLK+ Input Clock True 13 D − D ADC D Digital Output Complement 14 D + D ADC D Digital Output True 15 D − C ADC C Digital Output Complement 16 D + C ADC C Digital Output True 17 D − B ADC B Digital Output Complement 18 D + B ADC B Digital Output True 19 D − A ADC A Digital Output Complement 20 D + A ADC A Digital Output True 21 FCO− Frame Clock Output Complement 22 FCO+ Frame Clock Output True 23 DCO− Data Clock Output Complement 24 DCO+ Data Clock Output True 28 SCLK/DTP Serial Clock/Digital Test Pattern 29 SDIO/ODM Serial Data IO/Output Driver Mode 30 CSB Chip Select Bar 31 PDWN Power-Down 33 VIN + A ADC A Analog Input True 34 VIN − A ADC A Analog Input Complement 37 VIN − B ADC B Analog Input Complement 38 VIN + B ADC B Analog Input True 40 RBIAS External resistor sets the internal ADC core bias current 41 SENSE Reference Mode Selection 42 VREF Voltage Reference Input/Output

AD9287 Data Sheet


Pin No. Mnemonic Description 43 REFB Differential Reference (Negative) 44 REFT Differential Reference (Positive) 47 VIN + C ADC C Analog Input True 48 VIN − C ADC C Analog Input Complement

Data Sheet AD9287


EQUIVALENT CIRCUITS

VIN ± x

0596

6-03

0

Figure 6. Equivalent Analog Input Circuit

10Ω

10kΩ

10kΩ

CLK–10Ω

1.25V

CLK+

059

66-0

32

Figure 7. Equivalent Clock Input Circuit

SDIO/ODM350Ω

30kΩ

0596

6-0

35

Figure 8. Equivalent SDIO/ODM Input Circuit

DRVDD

DRGND

D– D+

V

V

V

V

059

66-0

05

Figure 9. Equivalent Digital Output Circuit

SCLK/DTPAND

PDWN30kΩ

1kΩ

0596

6-0

33

Figure 10. Equivalent SCLK/DTP and PDWN Input Circuit

100ΩRBIAS

0596

6-0

31

Figure 11. Equivalent RBIAS Circuit

AD9287 Data Sheet


CSB

70kΩ1kΩ

AVDD

059

66-

034

Figure 12. Equivalent CSB Input Circuit

SENSE1kΩ

059

66-0

36

Figure 13. Equivalent SENSE Circuit

VREF

6kΩ

059

66-0

37

Figure 14. Equivalent VREF Circuit

Data Sheet AD9287


TYPICAL PERFORMANCE CHARACTERISTICS

–1100 50

FREQUENCY (MHz)

AM

PL

ITU

DE

(d

BF

S)

–10

–30

–50

–70

–90

5 10 15 20 25 30 35 40 45

AIN = –0.5dBFSSNR = 49.21dB

ENOB = 7.88 BITSSFDR = 70.89dBc

0596

6-0

55

Figure 15. Single-Tone 32k FFT with fIN = 2.4 MHz, fSAMPLE = 100 MSPS

–1100 50

FREQUENCY (MHz)

AM

PL

ITU

DE

(d

BF

S)

–10

–30

–50

–70

–90

5 10 15 20 25 30 35 40 45



059

66-0

59

Figure 16. Single-Tone 32k FFT with fIN = 70 MHz, fSAMPLE = 100 MSPS

–1100 50

FREQUENCY (MHz)

AM

PL

ITU

DE

(d

BF

S)

–10

–30

–50

–70

–90

5 10 15 20 25 30 35 40 45



0596

6-06

0


–1100 50

FREQUENCY (MHz)

AM

PL

ITU

DE

(d

BF

S)

–10

–30

–50

–70

–90

5 10 15 20 25 30 35 40 45



0596

6-0

51


–1100 50

FREQUENCY (MHz)

AM

PL

ITU

DE

(d

BF

S)

–10

–30

–50

–70

–90

5 10 15 20 25 30 35 40 45



05

96

6-0

52


–1100 50

FREQUENCY (MHz)

AM

PL

ITU

DE

(d

BF

S)

–10

–30

–50

–70

–90

5 10 15 20 25 30 35 40 45



0596

6-05

3


AD9287 Data Sheet


80

4010 100

fSAMPLE (MSPS)

SN

R/S

FD

R (

dB

)

70

60

50

45

55

65

75

20 30 40 50 60 70 80 90

2V p-p, SFDR

2V p-p, SNR

059

66-

061

Figure 21. SNR/SFDR vs. fSAMPLE, fIN = 10.3 MHz, fSAMPLE = 100 MSPS

80

3010 100

fSAMPLE (MSPS)

SN

R/S

FD

R (

dB

)

70

60

50

40

20 30 40 50 60 70 80 90

2V p-p, SFDR

2V p-p, SNR

059

66-

062

Figure 22. SNR/SFDR vs. fSAMPLE, fIN = 35 MHz, fSAMPLE = 100 MSPS

80

0–60 0

ANALOG INPUT LEVEL (dBFS)

SN

R/S

FD

R (

dB

)

70

60

50

40

30

20

10

–50 –40 –30 –20 –10

2V p-p, SFDR

2V p-p, SNR

60dB REFERENCE

059

66-0

57

Figure 23. SNR/SFDR vs. Analog Input Level, fIN = 10.3 MHz, fSAMPLE = 100 MSPS

80

0–60 0

ANALOG INPUT LEVEL (dBFS)

SN

R/S

FD

R (

dB

)

70

60

50

40

30

20

10

–50 –40 –30 –20 –10

2V p-p, SFDR

2V p-p, SNR

60dB REFERENCE

059

66-0

58

Figure 24. SNR/SFDR vs. Analog Input Level, fIN = 35 MHz, fSAMPLE = 100 MSPS

–1100 50

FREQUENCY (MHz)

AM

PL

ITU

DE

(d

BF

S)

–10

–30

–50

–70

–90

5 10 15 20 25 30 35 40 45

AIN1 AND AIN2 = –7dBFSSFDR = 72.90dBcIMD2 = 70.43dBcIMD3 = 71.97dBc

059

66-0

49

Figure 25. Two-Tone 32k FFT with fIN1 = 15 MHz and fIN2 = 16 MHz, fSAMPLE = 100 MSPS

–1100 50

FREQUENCY (MHz)

AM

PL

ITU

DE

(d

BF

S)

–10

–30

–50

–70

–90

5 10 15 20 25 30 35 40 45

AIN1 AND AIN2 = –7dBFSSFDR = 71.14dBcIMD2 = 69.46dBcIMD3 = 70.33dBc

059

66-0

50

Figure 26. Two-Tone 32k FFT with fIN1 = 70 MHz and fIN2 = 71 MHz, fSAMPLE = 100 MSPS

Data Sheet AD9287


80

301

ANALOG INPUT FREQUENCY (MHz)

SN

R/S

FD

R (

dB

)

70

60

50

45

40

35

55

65

75

100010 100

2V p-p, SFDR (dBc)

2V p-p, SNR (dB)

059

66-0

63

Figure 27. SNR/SFDR vs. Analog Input Frequency, fSAMPLE = 100 MSPS

80

40–40

TEMPERATURE (°C)

SIN

AD

/SF

DR

(d

B)

70

60

50

45

55

65

75

–20 0 20 40 60 80

2V p-p, SFDR

2V p-p, SNR

059

66-0

64

Figure 28. SINAD/SFDR vs. Temperature, fIN = 10.3 MHz, fSAMPLE = 100 MSPS

1.0

–1.00 50 100 150 200 250

059

66

-065

CODE

INL

(L

SB

)

0.8

0.6

0.4

0.2

0

–0.2

–0.4

–0.6

–0.8

Figure 29. INL, fIN = 2.4 MHz, fSAMPLE = 100 MSPS

0.5

–0.50

CODE

DN

L (

LS

B)

0.3

0.1

–0.3

–0.2

–0.1

–0.4

0

0.2

0.4

50 100 150 200 250

059

66-0

66

Figure 30. DNL, fIN = 2.4 MHz, fSAMPLE = 100 MSPS

–45.0

–46.0

–45.5

–46.5

–47.0

–47.5

–48.010 15 20 25 35 4530 40 50

059

66-0

75

CM

RR

(d

B)


Figure 31. CMRR vs. Analog Input Frequency, fSAMPLE = 100 MSPS

0

–2.010 100

fSAMPLE (MSPS)

INP

UT

FU

LL

-SC

AL

E A

MP

LIT

UD

E (

dB

) –0.2

–0.4

–0.6

–0.8

–1.0

–1.2

–1.4

–1.6

–1.8

20 30 40 50 60 70 80 90

0596

6-0

48

Figure 32. Input Full-Scale Amplitude vs. fSAMPLE

AD9287 Data Sheet


–1100 50

FREQUENCY (MHz)

AM

PL

ITU

DE

(d

B)

–10

–30

–50

–70

–90

5 10 15 20 25 30 35 40 45

NPR = 40.12dBNOTCH = 18MHz

NOTCH WIDTH = 3MHz

059

66-0

54

Figure 33. Noise Power Ratio (NPR), fSAMPLE = 100 MSPS

FU

ND

AM

EN

TA

L L

EV

EL

(d

BF

S)

059

66-0

77

–10

0

–3

–2

–1

–4

–5

–6

–7

–8

–9

0 50 100 150 200 250 300 350 400 450 500

FREQUENCY (MHz)

–3dB CUTOFF = 295MHz

Figure 34. Full-Power Bandwidth vs. Frequency, fSAMPLE = 100 MSPS

Data Sheet AD9287


THEORY OF OPERATION The AD9287 architecture consists of a pipelined ADC divided into three sections: a 4-bit first stage followed by eight 1.5-bit stages and a final 3-bit flash. Each stage provides sufficient overlap to correct for flash errors in the preceding stage. The quantized outputs from each stage are combined into a final 8-bit result in the digital correction logic. The pipelined architecture permits the first stage to operate with a new input sample while the remaining stages operate with preceding samples. Sampling occurs on the rising edge of the clock.

Each stage of the pipeline, excluding the last, consists of a low resolution flash ADC connected to a switched-capacitor DAC and an interstage residue amplifier (for example, a multiplying digital-to-analog converter (MDAC)). The residue amplifier magnifies the difference between the reconstructed DAC output and the flash input for the next stage in the pipeline. One bit of redundancy is used in each stage to facilitate digital correction of flash errors. The last stage simply consists of a flash ADC.

The output staging block aligns the data, corrects errors, and passes the data to the output buffers. The data is then serialized and aligned to the frame and data clocks.

ANALOG INPUT CONSIDERATIONS The analog input to the AD9287 is a differential switched-capacitor circuit designed for processing differential input signals. The circuit can support a wide common-mode range while maintaining excellent performance. By using an input common-mode voltage of midsupply, users can minimize signal-dependent errors and achieve optimum performance.

S S

HCPAR

CSAMPLE

CSAMPLE

CPAR

VIN – x

H

S S

HVIN + x

H

0596

6-00

6

Figure 35. Switched-Capacitor Input Circuit

The clock signal alternately switches the input circuit between sample mode and hold mode (see Figure 35). When the input circuit is switched to sample mode, the signal source must be capable of charging the sample capacitors and settling within one-half of a clock cycle. A small resistor in series with each input can help reduce the peak transient current injected from the output stage of the driving source. In addition, low-Q inductors or ferrite beads can be placed on each leg of the input to reduce high differential capacitance at the analog inputs and therefore

achieve the maximum bandwidth of the ADC. Such use of low-Q inductors or ferrite beads is required when driving the converter front end at high IF frequencies. Either a shunt capacitor or two single-ended capacitors can be placed on the inputs to provide a matching passive network. This ultimately creates a low-pass filter at the input to limit unwanted broadband noise. See the AN-742 Application Note, the AN-827 Application Note, and the Analog Dialogue article “Transformer-Coupled Front-End for Wideband A/D Converters” (Volume 39, April 2005) for more information at www.analog.com. In general, the precise values depend on the application.

The analog inputs of the AD9287 are not internally dc-biased. Therefore, in ac-coupled applications, the user must provide this bias externally. Setting the device so that VCM = AVDD/2 is recommended for optimum performance, but the device can function over a wider range with reasonable performance, as shown in Figure 36 and Figure 37.

00.2 1.6

ANALOG INPUT COMMON-MODE VOLTAGE (V)

SN

R/S

FD

R (

dB

)

90

80

70

60

50

40

30

20

10

0.4 0.6 0.8 1.0 1.2 1.4

fIN = 2.4MHzfSAMPLE = 100MSPS

SFDR (dBc)

SNR (dB)

0596

6-06

7

Figure 36. SNR/SFDR vs. Common-Mode Voltage,

fIN = 2.4 MHz, fSAMPLE = 100 MSPS

00.2 1.6

ANALOG INPUT COMMON-MODE VOLTAGE (V)

SN

R/S

FD

R (

dB

)

90

80

70

60

50

40

30

20

10

0.4 0.6 0.8 1.0 1.2 1.4

fIN = 30MHzfSAMPLE = 100MSPS

SFDR (dBc)

SNR (dB)

0596

6-06

8

Figure 37. SNR/SFDR vs. Common-Mode Voltage,

fIN = 30 MHz, fSAMPLE = 100 MSPS





http://www.analog.com/transformer-coupled-fe?doc=ad9287.pdf

http://www.analog.com/transformer-coupled-fe?doc=ad9287.pdf



AD9287 Data Sheet


For best dynamic performance, the source impedances driving VIN + x and VIN − x should be matched such that common-mode settling errors are symmetrical. These errors are reduced by the common-mode rejection of the ADC. An internal reference buffer creates the positive and negative reference voltages, REFT and REFB, respectively, that define the span of the ADC core. The output common-mode of the reference buffer is set to midsupply, and the REFT and REFB voltages and span are defined as

REFT = 1/2 (AVDD + VREF) REFB = 1/2 (AVDD − VREF) Span = 2 × (REFT − REFB) = 2 × VREF

It can be seen from these equations that the REFT and REFB voltages are symmetrical about the midsupply voltage and, by definition, the input span is twice the value of the VREF voltage.

Maximum SNR performance is achieved by setting the ADC to the largest span in a differential configuration. In the case of the AD9287, the largest input span available is 2 V p-p.

Differential Input Configurations

There are several ways to drive the AD9287 either actively or passively; however, optimum performance is achieved by driving the analog input differentially. For example, using the AD8332 differential driver to drive the AD9287 provides excellent perfor-mance and a flexible interface to the ADC (see Figure 41) for baseband applications. This configuration is commonly used for medical ultrasound systems.

For applications where SNR is a key parameter, differential transformer coupling is the recommended input configuration (see Figure 38 and Figure 39), because the noise performance of most amplifiers is not adequate to achieve the true performance of the AD9287.

Regardless of the configuration, the value of the shunt capacitor, C, is dependent on the input frequency and may need to be reduced or removed.

2Vp-p

R

R

1CDIFF

C

1CDIFF IS OPTIONAL

49.9Ω

0.1μF

1kΩ

1kΩ

AGNDAVDD

ADT1-1WT1:1 Z RATIO

VIN – x

ADCAD9287

VIN + x

C

0596

6-0

08

Figure 38. Differential Transformer-Coupled Configuration

for Baseband Applications

ADCAD9287

2Vp-p

2.2pF 1kΩ

0.1μF

1kΩ

1kΩ

AVDD

ADT1-1WT1:1 Z RATIO16nH 16nH0.1μF

16nH

33Ω

33Ω

499Ω65Ω

VIN + x

VIN – x

059

66-0

47

Figure 39. Differential Transformer-Coupled Configuration

for IF Applications

Single-Ended Input Configuration

A single-ended input may provide adequate performance in cost-sensitive applications. In this configuration, SFDR and distortion performance degrade due to the large input common-mode swing. If the application requires a single-ended input configuration, ensure that the source impedances on each input are well matched in order to achieve the best possible performance. A full-scale input of 2 V p-p can be applied to the ADC’s VIN + x pin while the VIN − x pin is terminated. Figure 40 details a typical single-ended input configuration.

2V p-p

R

R

49.9Ω 0.1µF

0.1µF

AVDD

1kΩ 25Ω

1kΩ

1kΩ

AVDD

VIN – x

ADCAD9287

VIN + x

C

C0

596

6-0

09

1CDIFF

1CDIFF IS OPTIONAL Figure 40. Single-Ended Input Configuration

AD8332 1kΩ

187Ω

187Ω

0.1μF

0.1μF

0.1μF

1V p-p0.1μF

LNA

120nH

VGA

VOH

VIP

INH

22pF

LMD

VIN

LOP

LON

VOL

18nF 274Ω

VIN – x

ADCAD9287

VIN + x

059

66-0

07

LPF

+68pF

33Ω

33Ω

AVDD

AVDD

680nH

680nH

10kΩ

10kΩ

10kΩ

10kΩ

Figure 41. Differential Input Configuration Using the AD8332 with Two-Pole, 16 MHz Low-Pass Filter



http://www.analog.com/AD8332?doc=AD9287.pdf




Data Sheet AD9287


CLOCK INPUT CONSIDERATIONS For optimum performance, the AD9287 sample clock inputs (CLK+ and CLK−) should be clocked with a differential signal. This signal is typically ac-coupled to the CLK+ and CLK− pins via a transformer or capacitors. These pins are biased internally and require no additional biasing.

Figure 42 shows a preferred method for clocking the AD9287. The low jitter clock source is converted from a single-ended signal to a differential signal using an RF transformer. The back-to-back Schottky diodes across the secondary transformer limit clock excursions into the AD9287 to approximately 0.8 V p-p differential. This helps prevent the large voltage swings of the clock from feeding through to other portions of the AD9287, and it preserves the fast rise and fall times of the signal, which are critical to low jitter performance.

0.1µF

0.1µF

0.1µF0.1µF

SCHOTTKYDIODES:HSM2812

CLK+

50Ω 100Ω

CLK–

CLK+ADC

AD9287

Mini-Circuits®

ADT1-1WT, 1:1Z

XFMR

0596

6-02

4

Figure 42. Transformer-Coupled Differential Clock

Another option is to ac-couple a differential PECL signal to the sample clock input pins as shown in Figure 43. The AD9510/ AD9511/AD9512/AD9513/AD9514/AD9515 family of clock drivers offers excellent jitter performance.

100Ω

0.1µF

0.1µF0.1µF

0.1µF

240Ω240Ω

PECL DRIVER

CLK

CLK

CLK–

CLK+

ADCAD9287

05

966

-02

5

50Ω1 50Ω1

150Ω RESISTORS ARE OPTIONAL.

AD9510/AD9511/AD9512/AD9513/AD9514/AD9515

CLK+

CLK–

Figure 43. Differential PECL Sample Clock

100Ω

0.1µF

0.1µF0.1µF

0.1µFLVDS DRIVER

CLK

CLK

CLK–

CLK+

ADCAD9287

05

96

6-0

26

50Ω1 50Ω1


AD9510/AD9511/AD9512/AD9513/AD9514/AD9515

CLK+

CLK–

Figure 44. Differential LVDS Sample Clock

In some applications, it is acceptable to drive the sample clock inputs with a single-ended CMOS signal. In such applications, CLK+ should be driven directly from a CMOS gate, and the CLK− pin should be bypassed to ground with a 0.1 μF capacitor

in parallel with a 39 kΩ resistor (see Figure 45). Although the CLK+ input circuit supply is AVDD (1.8 V), this input is designed to withstand input voltages of up to 3.3 V and therefore offers several selections for the drive logic voltage.

0.1µF

0.1µF

0.1µF

39kΩ

CMOS DRIVER50Ω1

OPTIONAL100Ω

0.1µFCLK

CLK

CLK–

CLK+

ADCAD9287

0596

6-02

7


AD9510/AD9511/AD9512/AD9513/AD9514/AD9515

CLK+

Figure 45. Single-Ended 1.8 V CMOS Sample Clock

0.1µF

0.1µF

0.1µF

CMOS DRIVER

OPTIONAL100Ω

CLK

CLK

0.1µFCLK–

CLK+

ADCAD9287

059

66

-02

8

50Ω1


AD9510/AD9511/AD9512/AD9513/AD9514/AD9515

CLK+

Figure 46. Single-Ended 3.3 V CMOS Sample Clock

Clock Duty Cycle Considerations

Typical high speed ADCs use both clock edges to generate a variety of internal timing signals. As a result, these ADCs may be sensitive to the clock duty cycle. Commonly, a 5% tolerance is required on the clock duty cycle to maintain dynamic performance charac-teristics. The AD9287 contains a duty cycle stabilizer (DCS) that retimes the nonsampling edge, providing an internal clock signal with a nominal 50% duty cycle. This allows a wide range of clock input duty cycles without affecting the performance of the AD9287. When the DCS is on, noise and distortion performance are nearly flat for a wide range of duty cycles. However, some applications may require the DCS function to be off. If so, keep in mind that the dynamic range performance can be affected when operated in this mode. See the Memory Map section for more details on using this feature.

Jitter in the rising edge of the input is an important concern, and it is not reduced by the internal stabilization circuit. The duty cycle control loop does not function for clock rates of less than 20 MHz nominal. The loop has a time constant associated with it that must be considered in applications where the clock rate can change dynamically. This requires a wait time of 1.5 μs to 5 μs after a dynamic clock frequency increase (or decrease) before the DCS loop is relocked to the input signal. During the period that the loop is not locked, the DCS loop is bypassed and the internal device timing is dependent on the duty cycle of the input clock signal. In such applications, it may be appropriate to disable the duty cycle stabilizer. In all other applications, enabling the DCS circuit is recommended to maximize ac performance.













AD9287 Data Sheet


Clock Jitter Considerations

High speed, high resolution ADCs are sensitive to the quality of the clock input. The degradation in SNR at a given input frequency (fA) due only to aperture jitter (tJ) can be calculated by

SNR Degradation = 20 × log 10(1/2 × π × fA × tJ)

In this equation, the rms aperture jitter represents the root mean square of all jitter sources, including the clock input, analog input signal, and ADC aperture jitter. IF undersampling applications are particularly sensitive to jitter (see Figure 47).

The clock input should be treated as an analog signal in cases where aperture jitter may affect the dynamic range of the AD9287. Power supplies for clock drivers should be separated from the ADC output driver supplies to avoid modulating the clock signal with digital noise. Low jitter, crystal-controlled oscillators are the best clock sources. If the clock is generated from another type of source (by gating, dividing, or another method), it should be retimed by the original clock during the last step.

Refer to the AN-501 Application Note and to the AN-756 Application Note for more in-depth information about jitter performance as it relates to ADCs at www.analog.com.

1 10 100 1000

16 BITS

14 BITS

12 BITS

30

40

50

60

70

80

90

100

110

120

130

0.125ps0.25ps

0.5ps1.0ps2.0ps


10 BITS

8 BITS

RMS CLOCK JITTER REQUIREMENT

SN

R (

dB

)

059

66-0

38

Figure 47. Ideal SNR vs. Input Frequency and Jitter

Power Dissipation and Power-Down Mode

As shown in Figure 48, the power dissipated by the AD9287 is proportional to its sample rate. The digital power dissipation does not vary significantly because it is determined primarily by the DRVDD supply and bias current of the LVDS output drivers.

00 120

ENCODE (MSPS)C

UR

RE

NT

(m

A)

PO

WE

R (

mW

)

300

250

200

150

100

50

300

600

550

500

450

400

350

20 40 60 80 100

AVDD CURRENT

TOTAL POWER

DRVDD CURRENT

0596

6-06

9

Figure 48. Supply Current vs. fSAMPLE for fIN = 10.3 MHz, fSAMPLE = 100 MSPS







Data Sheet AD9287


By asserting the PDWN pin high, the AD9287 is placed into power-down mode. In this state, the ADC typically dissipates 3 mW. During power-down, the LVDS output drivers are placed into a high impedance state. If any of the SPI features are changed before the power-down feature is enabled, the chip continues to function after PDWN is pulled low without requiring a reset. The AD9287 returns to normal operating mode when the PDWN pin is pulled low. This pin is both 1.8 V and 3.3 V tolerant.

In power-down mode, low power dissipation is achieved by shutting down the reference, reference buffer, PLL, and biasing networks. The decoupling capacitors on REFT and REFB are discharged when entering power-down mode and must be recharged when returning to normal operation. As a result, the wake-up time is related to the time spent in the power-down mode: shorter cycles result in proportionally shorter wake-up times. With the recommended 0.1 μF and 2.2 μF decoupling capacitors on REFT and REFB, approximately 1 sec is required to fully discharge the reference buffer decoupling capacitors and approximately 375 μs is required to restore full operation.

There are several other power-down options available when using the SPI. The user can individually power down each channel or put the entire device into standby mode. The latter option allows the user to keep the internal PLL powered when fast wake-up times (~600 ns) are required. See the Memory Map section for more details on using these features.

Digital Outputs and Timing

The AD9287 differential outputs conform to the ANSI-644 LVDS standard on default power-up. This can be changed to a low power, reduced signal option (similar to the IEEE 1596.3 standard) via the SDIO/ODM pin or SPI. The LVDS standard can further reduce the overall power dissipation of the device by approximately 17 mW. See the SDIO/ODM Pin section or Table 16 in the Memory Map section for more information. The LVDS driver current is derived on-chip and sets the output current at each output equal to a nominal 3.5 mA. A 100 Ω differential termination resistor placed at the LVDS receiver inputs results in a nominal 350 mV swing at the receiver.

The AD9287 LVDS outputs facilitate interfacing with LVDS receivers in custom ASICs and FPGAs for superior switching performance in noisy environments. Single point-to-point net topologies are recommended with a 100 Ω termination resistor

placed as close to the receiver as possible. If there is no far-end receiver termination or there is poor differential trace routing, timing errors may result. To avoid such timing errors, it is recom-mended that each trace length be less than 24 inches and that the differential output traces be close together and at equal lengths. An example of the FCO and data stream with proper trace length and position is shown in Figure 49.

05

966-

056CH1 500mV/DIV = FCO

CH2 500mV/DIV = DATACH3 500mV/DIV = DCO

2.5ns/DIV

Figure 49. LVDS Output Timing Example in ANSI-644 Mode (Default)

An example of the LVDS output using the ANSI-644 standard (default) data eye and a time interval error (TIE) jitter histogram with trace lengths less than 24 inches on standard FR-4 material is shown in Figure 50. Figure 51 shows an example of trace lengths exceeding 24 inches on standard FR-4 material. Notice that the TIE jitter histogram reflects the decrease of the data eye opening as the edge deviates from the ideal position. It is the user’s responsibility to determine if the waveforms meet the timing budget of the design when the trace lengths exceed 24 inches. Additional SPI options allow the user to further increase the internal termination (increasing the current) of all four outputs in order to drive longer trace lengths (see Figure 52). Even though this produces sharper rise and fall times on the data edges and is less prone to bit errors, the power dissipation of the DRVDD supply increases when this option is used. In addition, notice in Figure 52 that the histogram is improved compared with that shown in Figure 51. See the Memory Map section for more details.





AD9287 Data Sheet


TIE

JIT

TE

R H

IST

OG

RA

M (

Hit

s)

500

–500

0

–1.0ns –0.5ns 0ns 0.5ns 1.0ns

EY

E D

IAG

RA

M V

OL

TA

GE

(V

)

EYE: ALL BITS ULS: 10000/15600

05

966-

04

3

100

50

0–100ps 0ps 100ps

Figure 50. Data Eye for LVDS Outputs in ANSI-644 Mode with Trace Lengths Less than 24 Inches on Standard FR-4, External 100 Ω Far Termination Only

200

–200

0

–1.0ns –0.5ns 0ns 0.5ns 1.0ns

EY

E D

IAG

RA

M V

OL

TA

GE

(V

)


059

66-

04

4

100

50

0–150ps –100ps –50ps 0ps 50ps 100ps 150ps

TIE

JIT

TE

R H

IST

OG

RA

M (

Hit

s)

Figure 51. Data Eye for LVDS Outputs in ANSI-644 Mode with Trace Lengths

Greater than 24 Inches on Standard FR-4, External 100 Ω Far Termination Only

200

400

–200

–400

0

–1.0ns –0.5ns 0ns 0.5ns 1.0ns

EY

E D

IAG

RA

M V

OL

TA

GE

(V

)


059

66-0

42

100

50

0–150ps –100ps –50ps 0ps 50ps 100ps 150ps

TIE

JIT

TE

R H

IST

OG

RA

M (

Hit

s)

Figure 52. Data Eye for LVDS Outputs in ANSI-644 Mode with 100 Ω Internal

Termination on and Trace Lengths Greater than 24 Inches on Standard FR-4, External 100 Ω Far Termination Only

The format of the output data is offset binary by default. An example of the output coding format can be found in Table 8. To change the output data format to twos complement, see the Memory Map section.

Table 8. Digital Output Coding

Code (VIN + x) − (VIN − x), Input Span = 2 V p-p (V)

Digital Output Offset Binary (D7 ... D0)

255 +1.00 1111 1111 128 0.00 1000 0000 127 −0.007813 0111 1111 0 −1.00 0000 0000

Data from each ADC is serialized and provided on a separate channel. The data rate for each serial stream is equal to 8 bits times the sample clock rate, with a maximum of 800 Mbps (8 bits × 100 MSPS = 800 Mbps). The lowest typical conversion rate is 10 MSPS. However, if lower sample rates are required for a specific application, the PLL can be set up via the SPI to allow encode rates as low as 5 MSPS. See the Memory Map section for details on enabling this feature.

Data Sheet AD9287


Two output clocks are provided to assist in capturing data from the AD9287. The DCO is used to clock the output data and is equal to four times the sample clock (CLK) rate. Data is clocked out of the AD9287 and must be captured on the rising and falling edges of the DCO that supports double data rate (DDR)

capturing. The FCO is used to signal the start of a new output byte and is equal to the sample clock rate. See the timing diagram shown in Figure 2 for more information.

Table 9. Flexible Output Test Modes Output Test Mode Bit Sequence Pattern Name Digital Output Word 1 Digital Output Word 2

Subject to Data Format Select

0000 Off (default) N/A N/A N/A 0001 Midscale short 1000 0000 (8-bit)

10 0000 0000 (10-bit) 1000 0000 0000 (12-bit) 10 0000 0000 0000 (14-bit)

Same Yes

0010 +Full-scale short 1111 1111 (8-bit) 11 1111 1111 (10-bit) 1111 1111 1111 (12-bit) 11 1111 1111 1111 (14-bit)

Same Yes

0011 −Full-scale short 0000 0000 (8-bit) 00 0000 0000 (10-bit) 0000 0000 0000 (12-bit) 00 0000 0000 0000 (14-bit)

Same Yes

0100 Checkerboard 1010 1010 (8-bit) 10 1010 1010 (10-bit) 1010 1010 1010 (12-bit) 10 1010 1010 1010 (14-bit)

0101 0101 (8-bit) 01 0101 0101 (10-bit) 0101 0101 0101 (12-bit) 01 0101 0101 0101 (14-bit)

No

0101 PN sequence long1 N/A N/A Yes 0110 PN sequence short1 N/A N/A Yes 0111 One-/zero-word toggle 1111 1111 (8-bit)

11 1111 1111 (10-bit) 1111 1111 1111 (12-bit) 11 1111 1111 1111 (14-bit)

0000 0000 (8-bit) 00 0000 0000 (10-bit) 0000 0000 0000 (12-bit) 00 0000 0000 0000 (14-bit)

No

1000 User input Register 0x19 to Register 0x1A Register 0x1B to Register 0x1C No 1001 1-/0-bit toggle 1010 1010 (8-bit)

10 1010 1010 (10-bit) 1010 1010 1010 (12-bit) 10 1010 1010 1010 (14-bit)

N/A No

1010 1× sync 0000 1111 (8-bit) 00 0001 1111 (10-bit) 0000 0011 1111 (12-bit) 00 0000 0111 1111 (14-bit)

N/A No

1011 One bit high 1000 0000 (8-bit) 10 0000 0000 (10-bit) 1000 0000 0000 (12-bit) 10 0000 0000 0000 (14-bit)

N/A No

1100 Mixed frequency 1010 0011 (8-bit) 10 0110 0011 (10-bit) 1010 0011 0011 (12-bit) 10 1000 0110 0111 (14-bit)

N/A No

1 All test mode options except PN sequence short and PN sequence long can support 8- to 14-bit word lengths in order to verify data capture to the receiver.



AD9287 Data Sheet


When the SPI is used, the DCO phase can be adjusted in 60° increments relative to the data edge. This enables the user to refine system timing margins if required. The default DCO+ and DCO− timing, as shown in Figure 2, is 90° relative to the output data edge.

A 10-, 12-, or 14-bit serial stream can also be initiated from the SPI. This allows the user to implement and test compatibility with higher resolution systems. However, when using the 12-bit option, the data stream stuffs four 0s at the end of the 12-bit serial data (see Figure 3).

When the SPI is used, all of the data outputs can also be inverted from their nominal state. This is not to be confused with inverting the serial stream to an LSB-first mode. In default mode, as shown in Figure 2, the MSB is first in the data output serial stream. However, this can be inverted so that the LSB is first in the data output serial stream (see Figure 4).

There are 12 digital output test pattern options available that can be initiated through the SPI. This is a useful feature when validating receiver capture and timing. Refer to Table 9 for the output bit sequencing options available. Some test patterns have two serial sequential words and can be alternated in various ways, depending on the test pattern chosen. Note that some patterns do not adhere to the data format select option. In addition, custom user-defined test patterns can be assigned in the 0x19, 0x1A, 0x1B, and 0x1C register addresses. All test mode options except PN sequence short and PN sequence long can support 8- to 14-bit word lengths in order to verify data capture to the receiver.

The PN sequence short pattern produces a pseudorandom bit sequence that repeats itself every 29 − 1 or 511 bits. A description of the PN sequence and how it is generated can be found in Section 5.1 of the ITU-T 0.150 (05/96) standard. The only difference is that the starting value must be a specific value instead of all 1s (see Table 10 for the initial values).

The PN sequence long pattern produces a pseudorandom bit sequence that repeats itself every 223 − 1 or 8,388,607 bits. A description of the PN sequence and how it is generated can be found in Section 5.6 of the ITU-T 0.150 (05/96) standard. The only differences are that the starting value must be a specific value instead of all 1s (see Table 10 for the initial values) and the AD9287 inverts the bit stream with relation to the ITU standard.

Table 10. PN Sequence

Sequence Initial Value

First Three Output Samples (MSB First)

PN Sequence Short 0x0df 0xbf, 0x93, 0x53 PN Sequence Long 0x029b80 0xf5, 0x91, 0xfd

Consult the Memory Map section for information on how to change these additional digital output timing features through the SPI.

SDIO/ODM Pin

The SDIO/ODM pin is for use in applications that do not require SPI mode operation. This pin can enable a low power, reduced signal option (similar to the IEEE 1596.3 reduced range link output standard) if it and the CSB pin are tied to AVDD during device power-up. This option should only be used when the digital output trace lengths are less than 2 inches from the LVDS receiver. When this option is used, the FCO, DCO, and outputs function normally, but the LVDS signal swing of all channels is reduced from 350 mV p-p to 200 mV p-p, allowing the user to further reduce the power on the DRVDD supply.

For applications where this pin is not used, it should be tied low. In this case, the device pin can be left open, and the 30 kΩ internal pull-down resistor pulls this pin low. This pin is only 1.8 V tolerant. If applications require this pin to be driven from a 3.3 V logic level, insert a 1 kΩ resistor in series with this pin to limit the current.

Table 11. Output Driver Mode Pin Settings

Selected ODM ODM Voltage Resulting Output Standard

Resulting FCO and DCO

Normal Operation

10 kΩ to AGND ANSI-644 (default)

ANSI-644 (default)

ODM AVDD Low power, reduced signal option

Low power, reduced signal option


Data Sheet AD9287


SCLK/DTP Pin

The SCLK/DTP pin is for use in applications that do not require SPI mode operation. This pin can enable a single digital test pattern if it and the CSB pin are held high during device power-up. When SCLK/DTP is tied to AVDD, the ADC channel outputs shift out the following pattern: 1000 0000. The FCO and DCO function normally while all channels shift out the repeatable test pattern. This pattern allows the user to perform timing alignment adjustments among the FCO, DCO, and output data. For normal operation, this pin should be tied to AGND through a 10 kΩ resistor. This pin is both 1.8 V and 3.3 V tolerant.

Table 12. Digital Test Pattern Pin Settings

Selected DTP DTP Voltage Resulting D + x and D − x

Resulting FCO and DCO

Normal Operation

10 kΩ to AGND Normal operation

Normal operation

DTP AVDD 1000 0000 Normal operation

Additional and custom test patterns can also be observed when commanded from the SPI port. Consult the Memory Map section for information about the options available.

CSB Pin

The CSB pin should be tied to AVDD for applications that do not require SPI mode operation. By tying CSB high, all SCLK and SDIO information is ignored. This pin is both 1.8 V and 3.3 V tolerant.

RBIAS Pin

To set the internal core bias current of the ADC, place a resistor (nominally equal to 10.0 kΩ) to ground at the RBIAS pin. The resistor current is derived on-chip and sets the AVDD current of the ADC to a nominal 260 mA at 100 MSPS. Therefore, it is imperative that at least a 1% tolerance on this resistor be used to achieve consistent performance.

Voltage Reference

A stable, accurate 0.5 V voltage reference is built into the AD9287. This is gained up internally by a factor of 2, setting VREF to 1.0 V, which results in a full-scale differential input span of 2 V p-p. The VREF is set internally by default; however, the VREF pin can be driven externally with a 1.0 V reference to improve accuracy.

When applying the decoupling capacitors to the VREF, REFT, and REFB pins, use ceramic low ESR capacitors. These capacitors should be close to the ADC pins and on the same layer of the PCB as the AD9287. The recommended capacitor values and configurations for the AD9287 reference pin are shown in Figure 53.

Table 13. Reference Settings

Selected Mode SENSE Voltage Resulting VREF (V)

Resulting Differential Span (V p-p)

External Reference

AVDD N/A 2 × external reference

Internal, 2 V p-p FSR

AGND to 0.2 V 1.0 2.0




AD9287 Data Sheet


Internal Reference Operation

A comparator within the AD9287 detects the potential at the SENSE pin and configures the reference. If SENSE is grounded, the reference amplifier switch is connected to the internal resistor divider (see Figure 53), setting VREF to 1 V.

The REFT and REFB pins establish the input span of the ADC core from the reference configuration. The analog input full-scale range of the ADC equals twice the voltage of the reference pin for either an internal or an external reference configuration.

If the reference of the AD9287 is used to drive multiple converters to improve gain matching, the loading of the refer-ence by the other converters must be considered. Figure 55 depicts how the internal reference voltage is affected by loading.

1µF 0.1µF

VREF

SENSE

0.5V

REFT

0.1µF

0.1µF 2.2µF

0.1µF

REFB

SELECTLOGIC

ADCCORE

+

VIN – x

VIN + x

0596

6-0

10

Figure 53. Internal Reference Configuration

1µF1 0.1µF1

VREF

SENSE

AVDD

0.5V

REFT

0.1µF

0.1µF 2.2µF

0.1µF

REFB

SELECTLOGIC

ADCCORE

+

VIN – x

VIN + x

05

966

-08

9

EXTERNALREFERENCE

1OPTIONAL. Figure 54. External Reference Operation

External Reference Operation

The use of an external reference may be necessary to enhance the gain accuracy of the ADC or to improve thermal drift characteristics. Figure 56 shows the typical drift characteristics of the internal reference in 1 V mode.

When the SENSE pin is tied to AVDD, the internal reference is disabled, allowing the use of an external reference. The external reference is loaded with an equivalent 6 kΩ load. An internal reference buffer generates the positive and negative full-scale references, REFT and REFB, for the ADC core. Therefore, the external reference must be limited to a nominal 1.0 V.

0 1.00.5 2.01.5 3.02.5 3.5

VR

EF E

RR

OR

(%

)

CURRENT LOAD (mA)

059

66-0

83

–30

–5

–10

–15

–20

–25

5

0

Figure 55. VREF Error vs. Load

0.02

–0.18–40 806040200–20

TEMPERATURE (°C)

VR

EF E

RR

OR

(%

)

0

–0.02

–0.04

–0.06

–0.08

–0.10

–0.12

–0.14

–0.16

0596

6-0

84

Figure 56. VREF Error vs. Temperature



Data Sheet AD9287


SERIAL PORT INTERFACE (SPI) The AD9287 serial port interface allows the user to configure the converter for specific functions or operations through a structured register space provided in the ADC. This may provide the user with additional flexibility and customization, depending on the application. Addresses are accessed via the serial port and can be written to or read from via the port. Memory is organized into bytes that can be further divided into fields, as documented in the Memory Map section. Detailed operational information can be found in the AN-877 Application Note, Interfacing to High Speed ADCs via SPI at www.analog.com.

There are three pins that define the SPI: SCLK, SDIO, and CSB (see Table 14). The SCLK pin is used to synchronize the read and write data presented to the ADC. The SDIO pin is a dual-purpose pin that allows data to be sent to and read from the internal ADC memory map registers. The CSB pin is an active low control that enables or disables the read and write cycles.

Table 14. Serial Port Pins Pin Function SCLK Serial Clock. The serial shift clock input. SCLK is used to

synchronize serial interface reads and writes. SDIO Serial Data Input/Output. A dual-purpose pin. The typical

role for this pin is as an input or output, depending on the instruction sent and the relative position in the timing frame.

CSB Chip Select Bar (Active Low). This control gates the read and write cycles.

The falling edge of the CSB in conjunction with the rising edge of the SCLK determines the start of the framing sequence. During an instruction phase, a 16-bit instruction is transmitted followed by one or more data bytes, which is determined by Bit Field W0 and Bit Field W1. An example of the serial timing and its definitions can be found in Figure 58 and Table 15. During normal operation, CSB is used to signal to the device that SPI commands are to be received and processed. When CSB is brought low, the device processes SCLK and SDIO to obtain instructions. Normally, CSB remains low until the communication cycle is complete. However, if connected to a slow device, CSB can be brought high between bytes, allowing older microcontrollers enough time to transfer data into shift registers. CSB can be stalled when transferring one, two, or three bytes of data. When W0 and W1 are set to 11, the device enters streaming mode and continues to process data, either reading or writing, until CSB is taken high to end the communication cycle. This allows complete memory transfers without requiring additional instruc-tions. Regardless of the mode, if CSB is taken high in the middle of a byte transfer, the SPI state machine is reset and the device waits for a new instruction.

In addition to the operation modes, the SPI port configuration influences how the AD9287 operates. For applications that do not require a control port, the CSB line can be tied and held high. This places the remainder of the SPI pins into their secondary modes, as defined in the SDIO/ODM Pin and SCLK/DTP Pin sections. CSB can also be tied low to enable 2-wire mode. When CSB is tied low, SCLK and SDIO are the only pins required for communication. Although the device is synchronized during power-up, the user should ensure that the serial port remains synchronized with the CSB line when using this mode. When operating in 2-wire mode, it is recommended to use a 1-, 2-, or 3-byte transfer exclusively. Without an active CSB line, streaming mode can be entered but not exited.

In addition to word length, the instruction phase determines if the serial frame is a read or write operation, allowing the serial port to be used to both program the chip and read the contents of the on-chip memory. If the instruction is a readback operation, performing a readback causes the SDIO pin to change from an input to an output at the appropriate point in the serial frame.

Data can be sent in MSB- or LSB-first mode. MSB-first mode is the default at power-up and can be changed by adjusting the configuration register. For more information about this and other features, see the AN-877 Application Note, Interfacing to High Speed ADCs via SPI at www.analog.com.

HARDWARE INTERFACE The pins described in Table 14 compose the physical interface between the user’s programming device and the serial port of the AD9287. The SCLK and CSB pins function as inputs when using the SPI. The SDIO pin is bidirectional, functioning as an input during write phases and as an output during readback.

If multiple SDIO pins share a common connection, care should be taken to ensure that proper VOH levels are met. Assuming the same load for each AD9287, Figure 57 shows the number of SDIO pins that can be connected together and the resulting VOH level. This interface is flexible enough to be controlled by either serial PROMS or PIC microcontrollers, providing the user with an alternative method, other than a full SPI controller, to program the ADC (see the AN-812 Application Note at www.analog.com).











AD9287 Data Sheet


059

66-

090

NUMBER OF SDIO PINS CONNECTED TOGETHER

VO

H (

V)

1.715

1.720

1.725

1.730

1.735

1.740

1.745

1.750

1.755

1.760

1.765

1.770

1.775

1.780

1.785

1.790

1.795

1.800

0 302010 40 50 60 70 80 90 100

Figure 57. SDIO Pin Loading

If the user chooses not to use the SPI, these dual-function pins serve their secondary functions when the CSB is strapped to AVDD during device power-up. See the Theory of Operation section for details on which pin-strappable functions are supported on the SPI pins.

For users who wish to operate the ADC without using the SPI, remove any connections from the CSB, SCLK/DTP, and SDIO/ ODM pins. By disconnecting these pins from the control bus, the ADC can function in its most basic operation. Each of these pins has an internal termination that floats to its respective level.

DON’T CARE

DON’T CAREDON’T CARE

DON’T CARE

SDIO

SCLK

CSB

tS tDH

tHI tCLK

tLO

tDS tH

R/W W1 W0 A12 A11 A10 A9 A8 A7 D5 D4 D3 D2 D1 D0

059

66-0

12

Figure 58. Serial Timing Details

Table 15. Serial Timing Definitions Parameter Timing (Minimum, ns) Description tDS 5 Setup time between the data and the rising edge of SCLK tDH 2 Hold time between the data and the rising edge of SCLK tCLK 40 Period of the clock tS 5 Setup time between CSB and SCLK tH 2 Hold time between CSB and SCLK tHI 16 Minimum period that SCLK should be in a logic high state tLO 16 Minimum period that SCLK should be in a logic low state tEN_SDIO 10 Minimum time for the SDIO pin to switch from an input to an output relative to the SCLK

falling edge (not shown in Figure 58) tDIS_SDIO 10 Minimum time for the SDIO pin to switch from an output to an input relative to the SCLK

rising edge (not shown in Figure 58)

Data Sheet AD9287


MEMORY MAP READING THE MEMORY MAP TABLE Each row in the memory map register table (Table 16) has eight address locations. The memory map is divided into three sections: the chip configuration register map (Address 0x00 to Address 0x02), the device index and transfer register map (Address 0x05 and Address 0xFF), and the ADC functions register map (Address 0x08 to Address 0x22).

The leftmost column of the memory map indicates the register address number, and the default value is shown in the second rightmost column. The (MSB) Bit 7 column is the start of the default hexadecimal value given. For example, Address 0x09, the clock register, has a default value of 0x01, meaning that Bit 7 = 0, Bit 6 = 0, Bit 5 = 0, Bit 4 = 0, Bit 3 = 0, Bit 2 = 0, Bit 1 = 0, and Bit 0 = 1, or 0000 0001 in binary. This setting is the default for the duty cycle stabilizer in the on condition. By writing a 0 to Bit 6 of this address followed by a 0x01 in Register 0xFF (transfer bit), the duty cycle stabilizer turns off. It is important to follow each writing sequence with a transfer bit to update the SPI registers. For more information on this and other functions, consult the AN-877 Application Note, Interfacing to High Speed ADCs via SPI at www.analog.com.

RESERVED LOCATIONS Undefined memory locations should not be written to except when writing the default values suggested in this data sheet. Addresses that have values marked as 0 should be considered reserved and have a 0 written into their registers during power-up.

DEFAULT VALUES When the AD9287 comes out of a reset, critical registers are preloaded with default values. These values are indicated in Table 16, where an X refers to an undefined feature.

LOGIC LEVELS An explanation of various registers follows: “Bit is set” is synonymous with “bit is set to Logic 1” or “writing Logic 1 for the bit.” Similarly, “clear a bit” is synonymous with “bit is set to Logic 0” or “writing Logic 0 for the bit.”





AD9287 Data Sheet


Table 16. Memory Map Register

Addr. (Hex) Register Name

(MSB) Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1

(LSB) Bit 0

Default Value (Hex)

Default Notes/ Comments

Chip Configuration Registers

00 chip_port_config 0 LSB first 1 = on 0 = off (default)

Soft reset 1 = on 0 = off (default)

1 1 Soft reset 1 = on 0 = off (default)

LSB first 1 = on 0 = off (default)

0 0x18 The nibbles should be mirrored so that LSB- or MSB-first mode is set cor-rectly regardless of shift mode.

01 chip_id 8-bit Chip ID Bits [7:0] (AD9287 = 0x05), (default)

0x05 Default is unique chip ID, different for each device. This is a read-only register.

02 chip_grade X Child ID [6:4] (identify device variants of Chip ID) 011 = 100 MSPS

X X X X Read only

Child ID used to differentiate graded devices.

Device Index and Transfer Registers

05 device_index_A X X Clock Channel DCO 1 = on 0 = off (default)

Clock Channel FCO 1 = on 0 = off (default)

Data Channel D 1 = on (default)0 = off

Data Channel C 1 = on (default)0 = off

Data Channel B 1 = on (default)0 = off

Data Channel A 1 = on (default) 0 = off

0x0F Bits are set to determine which on-chip device receives the next write command.

FF device_update X X X X X X X SW transfer 1 = on 0 = off (default)

0x00 Synchronously transfers data from the master shift register to the slave.

ADC Functions

08 modes X X X X X Internal power-down mode 000 = chip run (default) 001 = full power-down 010 = standby 011 = reset

0x00 Determines various generic modes of chip operation.

09 clock X X X X X X X Duty cycle stabilizer 1 = on (default) 0 = off

0x01 Turns the internal duty cycle stabilizer on and off.

0D test_io User test mode 00 = off (default) 01 = on, single alternate 10 = on, single once 11 = on, alternate once

Reset PN long gen 1 = on 0 = off (default)

Reset PN short gen 1 = on 0 = off (default)

Output test mode—see Table 9 in the Digital Outputs and Timing section 0000 = off (default) 0001 = midscale short 0010 = +FS short 0011 = −FS short 0100 = checkerboard output 0101 = PN 23 sequence 0110 = PN 9 sequence 0111 = one-/zero-word toggle 1000 = user input 1001 = 1-/0-bit toggle 1010 = 1× sync 1011 = one bit high 1100 = mixed bit frequency (format determined by output_mode)

0x00 When this reg-ister is set, the test data is placed on the output pins in place of normal data.


Data Sheet AD9287


Addr. (Hex) Register Name

(MSB) Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1

(LSB) Bit 0

Default Value (Hex)

Default Notes/ Comments

14 output_mode X 0 = LVDS ANSI-644 (default) 1 = LVDS low power (IEEE 1596.3 similar)

X X X Output invert 1 = on 0 = off (default)

00 = offset binary (default) 01 = twos complement

0x00 Configures the outputs and the format of the data.

15 output_adjust X X Output driver termination 00 = none (default) 01 = 200 Ω 10 = 100 Ω 11 = 100 Ω

X X X X 0x00 Determines LVDS or other output properties. Primarily func-tions to set the LVDS span and common-mode levels in place of an external resistor.

16 output_phase X X X X 0011 = output clock phase adjust (0000 through 1010) 0000 = 0° relative to data edge 0001 = 60° relative to data edge 0010 = 120° relative to data edge 0011 = 180° relative to data edge (default) 0101 = 300° relative to data edge 0110 = 360° relative to data edge 1000 = 480° relative to data edge 1001 = 540° relative to data edge 1010 = 600° relative to data edge 1011 to 1111 = 660° relative to data edge

0x03 On devices that utilize global clock divide, determines which phase of the divider output is used to supply the output clock. Internal latching is unaffected.

19 user_patt1_lsb B7 B6 B5 B4 B3 B2 B1 B0 0x00 User-defined pattern, 1 LSB.

1A user_patt1_msb B15 B14 B13 B12 B11 B10 B9 B8 0x00 User-defined pattern, 1 MSB.

1B user_patt2_lsb B7 B6 B5 B4 B3 B2 B1 B0 0x00 User-defined pattern, 2 LSB.

1C user_patt2_msb B15 B14 B13 B12 B11 B10 B9 B8 0x00 User-defined pattern, 2 MSB.

21 serial_control LSB first 1 = on 0 = off (default)

X X X <10 MSPS, low encode rate mode 1 = on 0 = off (default)

000 = 8 bits (default, normal bit stream) 001 = 8 bits 010 = 10 bits 011 = 12 bits 100 = 14 bits

0x00 Serial stream control. Default causes MSB first and the native bit stream (global).

22 serial_ch_stat X X X X X X Channel output reset 1 = on 0 = off (default)

Channel power-down 1 = on 0 = off (default)

0x00 Used to power down individual sections of a converter (local).

AD9287 Data Sheet


Power and Ground Recommendations

When connecting power to the AD9287, it is recommended that two separate 1.8 V supplies be used: one for analog (AVDD) and one for digital (DRVDD). If only one supply is available, it should be routed to the AVDD first and then tapped off and isolated with a ferrite bead or a filter choke preceded by decoupling capacitors for the DRVDD. The user can employ several different decoupling capacitors to cover both high and low frequencies. These should be located close to the point of entry at the PC board level and close to the parts, with minimal trace lengths.

A single PC board ground plane should be sufficient when using the AD9287. With proper decoupling and smart parti-tioning of the PC board’s analog, digital, and clock sections, optimum performance can be easily achieved.

Exposed Paddle Thermal Heat Slug Recommendations

It is required that the exposed paddle on the underside of the ADC be connected to analog ground (AGND) to achieve the best electrical and thermal performance of the AD9287. An exposed continuous copper plane on the PCB should mate to the AD9287 exposed paddle, Pin 0. The copper plane should have several vias to achieve the lowest possible resistive thermal path for heat dissipation to flow through the bottom of the PCB. These vias should be solder-filled or plugged.

To maximize the coverage and adhesion between the ADC and PCB, partition the continuous copper plane by overlaying a silkscreen on the PCB into several uniform sections. This provides several tie points between the ADC and PCB during the reflow process, whereas using one continuous plane with no partitions only guarantees one tie point. See Figure 59 for a PCB layout example. For detailed information on packaging and the PCB layout of chip scale packages, see the AN-772 Application Note, A Design and Manufacturing Guide for the Lead Frame Chip Scale Package (LFCSP) at www.analog.com.

SILKSCREEN PARTITIONPIN 1 INDICATOR

059

66-0

13

Figure 59. Typical PCB Layout







Data Sheet AD9287


EVALUATION BOARD The AD9287 evaluation board provides all of the support cir-cuitry required to operate the ADC in its various modes and configurations. The converter can be driven differentially using a transformer (default) or an AD8332 driver. The ADC can also be driven in a single-ended fashion. Separate power pins are provided to isolate the DUT from the drive circuitry of the AD8332. Each input configuration can be selected by changing the connection of various jumpers (see Figure 62 to Figure 66). Figure 60 shows the typical bench characterization setup used to evaluate the ac performance of the AD9287. It is critical that the signal sources used for the analog input and clock have very low phase noise (<1 ps rms jitter) to realize the optimum performance of the converter. Proper filtering of the analog input signal to remove harmonics and lower the integrated or broadband noise at the input is also necessary to achieve the specified noise performance.

See Figure 62 to Figure 70 for the complete schematics and layout diagrams demonstrating the routing and grounding techniques that should be applied at the system level.

POWER SUPPLIES This evaluation board has a wall-mountable switching power supply that provides a 6 V, 2 A maximum output. Connect the supply to the rated 100 V ac to 240 V ac wall outlet at 47 Hz to 63 Hz. The other end of the supply is a 2.1 mm inner diameter jack that connects to the PCB at P503. Once on the PC board, the 6 V supply is fused and conditioned before connecting to three low dropout linear regulators that supply the proper bias to each of the various sections on the board.

When operating the evaluation board in a nondefault condition, L504 to L507 can be removed to disconnect the switching power supply. This enables the user to bias each

section of the board individually. Use P501 to connect a different supply for each section. At least one 1.8 V supply is needed for AVDD_DUT and DRVDD_DUT; however, it is recommended that separate supplies be used for analog and digital signals and that each supply have a current capability of 1 A. To operate the evaluation board using the VGA option, a separate 5.0 V analog supply (AVDD_5 V) is needed. To operate the evaluation board using the SPI and alternate clock options, a separate 3.3 V analog supply (AVDD_3.3 V) is needed in addition to the other supplies.

INPUT SIGNALS When connecting the clock and analog sources to the evaluation board, use clean signal generators with low phase noise, such as Rohde & Schwarz SMHU or HP8644 signal generators or the equivalent, as well as a 1 m, shielded, RG-58, 50 Ω coaxial cable. Enter the desired frequency and amplitude from the ADC specifications tables. Typically, most Analog Devices evaluation boards can accept approximately 2.8 V p-p or 13 dBm sine wave input for the clock. When connecting the analog input source, it is recommended to use a multipole, narrow-band, band-pass filter with 50 Ω terminations. Good choices of such band-pass filters are available from TTE, Allen Avionics, and K&L Microwave, Inc. The filter should be connected directly to the evaluation board if possible.

OUTPUT SIGNALS The default setup uses the Analog Devices HSC-ADC-FIFO5-INTZ to interface with the Analog Devices standard dual-channel FIFO data capture board (HCS-ADC-EVALCZ). Two of the eight channels can be evaluated at the same time. For more information on the channel settings and optional settings of these boards, visit www.analog.com/FIFO.

ROHDE & SCHWARZ,SMHU,

2V p-p SIGNALSYNTHESIZER

ROHDE & SCHWARZ,SMHU,

2V p-p SIGNALSYNTHESIZER

BAND-PASSFILTER

XFMRINPUT

CLK

CH A TO CH D8-BIT

SERIALLVDS

USBCONNECTION

AD9287EVALUATION BOARD

HSC-ADC-EVALCZFIFO DATACAPTURE

BOARD

PCRUNNING

ADCANALYZER

AND SPIUSER

SOFTWARE

1.8V– +– +

AV

DD

_DU

T

AV

DD

_3.3

V

DR

VD

D_D

UT

GN

D

GN

D

– +5.0V

GN

D

AV

DD

_5V

1.8V

6V DC2A MAX

WALL OUTLET100V TO 240V AC47Hz TO 63Hz

SWITCHINGPOWERSUPPLY

– +

GN

D

3.3V– +

VC

C

GN

D

3.3V

SPI SPISPI

05

966

-01

4

INTERPOSERBOARD

SPI Figure 60. Evaluation Board Connection





http://www.analog.com/FIFO?doc=AD9287.pdf

AD9287 Data Sheet


DEFAULT OPERATION AND JUMPER SELECTION SETTINGS The following is a list of the default and optional settings or modes allowed on the AD9287 Rev. A evaluation board.

POWER: Connect the switching power supply that is provided with the evaluation kit between a rated 100 V ac to 240 V ac wall outlet at 47 Hz to 63 Hz and P503.

AIN: The evaluation board is set up for a transformer-coupled analog input with an optimum 50 Ω impedance match of 190 MHz of bandwidth (see Figure 61). For more bandwidth response, the differential capacitor across the analog inputs can be changed or removed. The common mode of the analog inputs is developed from the center tap of the transformer or AVDD_DUT/2.

0

AM

PL

ITU

DE

(d

BF

S)

FREQUENCY (MHz)

0596

6-0

88

0

–16

–14

–12

–10

–8

–6

–4

–2

50 100 150 200 250 300 350 400 450 500

–3dB CUTOFF = 190MHz

Figure 61. Evaluation Board Full-Power Bandwidth

VREF: VREF is set to 1.0 V by tying the SENSE pin to ground, R237. This causes the ADC to operate in 2.0 V p-p full-scale range. A separate external reference option using the ADR510 is also included on the evaluation board. Populate R231 and R235 and remove C214. Proper use of the VREF options is noted in the Voltage Reference section.

RBIAS: RBIAS has a default setting of 10 kΩ (R201) to ground and is used to set the ADC core bias current.

CLOCK: The default clock input circuitry is derived from a simple transformer-coupled circuit using a high bandwidth 1:1 impedance ratio transformer (T201) that adds a very low amount of jitter to the clock path. The clock input is 50 Ω terminated and ac-coupled to handle single-ended sine wave types of inputs. The transformer converts the single-ended input to a differential signal that is clipped before entering the ADC clock inputs.

A differential LVPECL clock can also be used to clock the ADC input using the AD9515 (U202). Populate R225 and R227 with 0 Ω resistors and remove R217 and R218 to disconnect the default clock path inputs. In addition, populate C207 and C208 with a 0.1 μF capacitor and remove C210 and C211 to disconnect the default clock path outputs. The AD9515 has many pin-strappable options that are set to a default mode of operation. Consult the AD9515 data sheet for more information about these and other options.

In addition, an on-board oscillator is available on the OSC201 and can act as the primary clock source. The setup is quick and involves installing R212 with a 0 Ω resistor and setting the enable jumper (J205) to the on position. If the user wishes to employ a different oscillator, two oscillator footprint options are available (OSC201) to check the ADC performance.

PDWN: To enable the power-down feature, short J201 to AVDD on the PDWN pin.

SCLK/DTP: To enable the digital test patterns on the digital outputs of the ADC, use J204. If J204 is tied to AVDD during device power-up, Test Pattern 1000 0000 is enabled. See the SCLK/DTP Pin section for details.

SDIO/ODM: To enable the low power, reduced signal option (similar to the IEEE 1595.3 reduced range link LVDS output standard), use J203. If J203 is tied to AVDD during device power-up, it enables the LVDS outputs in a low power, reduced signal option from the default ANSI-644 standard. This option changes the signal swing from 350 mV p-p to 200 mV p-p, reducing the power of the DRVDD supply. See the SDIO/ODM Pin section for more details.

CSB: To enable processing of the SPI information on the SDIO and SCLK pins, tie J202 low in the always enable mode. To ignore the SDIO and SCLK information, tie J202 to AVDD.

Non-SPI Mode: For users who wish to operate the DUT without using SPI, remove Jumpers J202, J203, and J204. This disconnects the CSB, SCLK/DTP, and SDIO/ODM pins from the control bus, allowing the DUT to operate in its simplest mode. Each of these pins has internal termination and will float to its respective level.

D + x, D − x: If an alternative data capture method to the setup shown in Figure 60 is used, optional receiver terminations, R206 to R211, can be installed next to the high speed backplane connector.


http://www.analog.com/ADR510?doc=AD9287.pdf




Data Sheet AD9287


ALTERNATIVE ANALOG INPUT DRIVE CONFIGURATION The following is a brief description of the alternative analog input drive configuration using the AD8332 dual VGA. If this drive option is in use, some components may need to be populated, in which case all the necessary components are listed in Table 17. For more details on the AD8332 dual VGA, including how it works and its optional pin settings, consult the AD8332 data sheet.

To configure the analog input to drive the VGA instead of the default transformer option, the following components need to be removed and/or changed.

Remove R102, R115, R128, R141, R161, R162, R163, R164, T101, T102, T103, and T104 in the default analog input path.

Populate R101, R114, R127, and R140 with 0 Ω resistors in the analog input path.

Populate R105, R113, R118, R124, R131, R137, R151, and R160 with 0 Ω resistors in the analog input path to connect the AD8332.

Populate R152, R153, R154, R155, R156, R157, R158, R159, C103, C105, C110, C112, C117, C119, C124, and C126 with 10 kΩ resistors to provide an input common-mode level to the ADC analog inputs.

Remove R305, R306, R313, R314, R405, R406, R412, and R424 to configure the AD8332.

In this configuration, L301 to L308 and L401 to L408 are populated with 0 Ω resistors to allow signal connection and use of a filter if additional requirements are necessary.






AD9287 Data Sheet


CHANNEL AP101

AIN

AIN

VGA INPUT CONNECTION




1

2

3

6

5

4

T101

CM1

CM1 FB10310Ω

FB10210Ω

FB10110Ω

C1042.2pF

VIN_A

VIN_A

P102DNP

CM1

INH1

CH_A

AVDD_DUT

CH_A

R1040Ω

AVDD_DUT

AVDD_DUT

C106DNPC107

0.1µF

C103DNP

C105DNP

C1010.1µF

C1020.1µF

E101

R161499Ω

R152DNP

R113DNP

R105DNP

R11033Ω

R107DNP

R106DNP

R1121kΩ

R1111kΩ

R10833Ω

R101DNP

R10264.9Ω

R1030Ω

R1091kΩ

CHANNEL BP103

AIN 1

2

3

6

5

4

T102

CM2

CM2 FB10610Ω

FB10510Ω

FB10410Ω

C1112.2pF

VIN_B

VIN_B

P104DNP

CM2

INH2 CH_B

AVDD_DUT

CH_B

R1160Ω

AVDD_DUT

AVDD_DUT

C113DNPC114

0.1µF

C110DNP

C112DNP

C1080.1µF

C1090.1µF

E102

R162499Ω

R153DNP

R124DNP

R118DNP

R12233Ω

R120DNP

R119DNP

R1261kΩ

R1251kΩ

R12133Ω

R114DNP

R11564.9Ω

R1170Ω

R1231kΩ

CHANNEL CP105

AIN

1

2

3

6

5

4

T103

CM3

CM3 FB10910Ω

FB10810Ω

FB10710Ω

C1182.2pF

VIN_C

VIN_C

P106DNP

CM3

INH3

CH_C

AVDD_DUT

CH_C

R1300Ω

AVDD_DUT

AVDD_DUT

C120DNPC121

0.1µF

C117DNP

C119DNP

C1150.1µF

C1160.1µF

E103

R163499Ω

R154DNP

R137DNP

R131DNP

R13633Ω

R133DNP

R132DNP

R1391kΩ

R1381kΩ

R13433Ω

R127DNP

R12864.9Ω

R1290Ω

R1351kΩ

CHANNEL DP107

AIN 1

2

3

6

5

4

T104

CM4

CM4 FB11210Ω

FB11110Ω

R1430Ω

C1252.2pF

VIN_D

VIN_D

P108DNP

CM4

INH4 CH_D

AVDD_DUT

CH_D

FB11010Ω

AVDD_DUT

AVDD_DUT

C127DNPC128

0.1µF

C124DNP

C126DNP

R159DNP

C1220.1µF

C1230.1µF

E104

R164499Ω

R155DNP

R160DNP

R151DNP

R14733Ω

R145DNP

R144DNP

R1501kΩ

R1491kΩ

R14633Ω

R140DNP

R14164.9Ω

R1420Ω

R1481kΩ

R156DNP

R157DNP

AIN

AIN

AIN

R158DNP

DNP: DO NOT POPULATE

059

66-

015

Figure 62. Evaluation Board Schematic, DUT Analog Inputs

Data Sheet AD9287


CS

B

C21

70.

1µF

C22

00.

1µF

C22

10.

1µF

C21

80.

1µF

C21

90.

1µF

C22

30.

1µF

C22

20.

1µF

AV

DD

_3.3

V

CL

K

CL

KB

GND

GN

D_P

AD

OU

T0

OU

T0B

OU

T1

OU

T1B

RSET

S0

S1

S10

S2

S3

S4

S5

S6

S7

S8

S9

SY

NC

B VREF

VS

SIG

NA

L =

DN

C;2

7,28

INP

UT

EN

CO

DE

EN

C

EN

CD

NP

CL

OC

K C

IRC

UIT

OP

TIO

NA

L C

LO

CK

DR

IVE

CIR

CU

IT

DIS

AB

LE

EN

AB

LE

OP

TIO

NA

L C

LO

CK

OS

CIL

LA

TO

R

C22

40.

1µF

R21

410

kΩ

R21

510

kΩ

14

78

1 3 5

12 10

OS

C20

1

VF

AC

3H-L

C20

70.

1µF

DN

P

C20

80.

1µF

DN

P

C20

90.

1µF

DN

P

C21

50.

1µF

DN

P

C21

10.

1µF

C21

00.

1µF

E20

2

1E

201

P20

1

P20

3

AV

DD

_3.3

V

12

6

7

25

8

16

9

15

10

14

11

13

181923 22

32

1

31

33

U20

2

SIG

NA

L =

AV

DD

_3.3

V;4

,17,

20,2

1,24

,26,

29,3

0A

D95

15

3

2

1

CR

201

HS

MS

2812

R22

0D

NP

R24

024

3Ω

R24

310

0Ω

R24

124

3ΩR24

210

0Ω

6543 2 1T

201

1

2

J205

C20

50.

1µF

C21

60.

1µF

R21

349

.9kΩ

R21

60Ω

R22

110

kΩ

R21

20Ω D

NP

R21

9D

NP

S0

S1

S2

S3

S4

S5

S6

S7

S8

S9

S10

OP

T_C

LK

OP

T_C

LK

CL

K

AV

DD

_3.3

V

OP

T_C

LK

OP

T_C

LK

CL

K

CL

K

LV

PE

CL

OU

TP

UT

LV

DS

OU

TP

UT

CL

K

AV

DD

_3.3

V

11

E20

3

AV

DD

_3.3

V

VC

C

GN

DO

UT

OE

OE

'

GN

D'

VC

C'

OU

T'

R24

4D

NP

R24

50Ω

S4

S0

S5

S3

S2

S1

AV

DD

_3.3

V

AV

DD

_3.3

V

AV

DD

_3.3

V

AV

DD

_3.3

V

AV

DD

_3.3

V

AV

DD

_3.3

V

R24

6D

NP

R24

70Ω

R24

8D

NP

R24

90Ω

R25

0D

NP

R25

10Ω

R25

2D

NP

R25

30Ω

R25

4D

NP

R25

50Ω

R25

6D

NP

R25

70Ω

S10S

6

S9

S8

S7

AV

DD

_3.3

V

AV

DD

_3.3

V

AV

DD

_3.3

V

AV

DD

_3.3

V

AV

DD

_3.3

V

R25

8D

NP

R25

90Ω

R26

0D

NP

R26

10Ω

R26

2D

NP

R26

30Ω

R26

4D

NP

R26

50Ω

A1

A2

A3

A4

A5

A6

A7

A8

A9

GN

DA

B1

GN

DA

B10

GN

DA

B2

GN

DA

B3

GN

DA

B4

GN

DA

B5

GN

DA

B6

GN

DA

B7

GN

DA

B8

GN

DA

B9

GN

DC

D1

GN

DC

D10

GN

DC

D2

GN

DC

D3

GN

DC

D4

GN

DC

D5

GN

DC

D6

GN

DC

D7

GN

DC

D8

GN

DC

D9

HE

AD

ER

646

9169

-1

R20

5 T

O R

211

OP

TIO

NA

L O

UT

PU

TT

ER

MIN

AT

ION

S

DIG

ITA

L O

UT

PU

TS

CS

B3_

CH

B

SD

I_C

HB

SD

O_C

HA

CS

B2_

CH

A

CS

B1_

CH

A

SD

I_C

HA

SC

LK

_CH

A

R20

6D

NP

R21

1D

NP

R21

0D

NP

R20

9D

NP

R20

8D

NP

P20

2

R20

7D

NP

SC

LK

_CH

B

DC

OC

10

C9

C8

C7

C6

C5

C4

C3

C2

C1

C10

50 49 48 47 46 45 44 43 42 41 20 19 18 17 16 15 14 13 12

D10 D

9

D8

D7

D6

D5

D4

D3

D2

D1

B10 B

9

B8

B7

B6

B5

B4

B3

B2

B1

11

CH

D

CH

C

CH

B

CH

A

FC

O

DC

O

CH

D

CH

C

CH

B

CH

A

FC

O

SD

O_C

HB

CS

B4_

CH

B

4060 19 2122452562683132333435363738 291030 223 3242851525354555657583959 727

OD

M E

NA

BL

E

CL

K

AV

DD

CL

K+

CL

K–

D + A

D + B

D + C

D + D

D – A

D – B

D – C

D – D

DCO+

DCO–

DR

VD

D

DR

GN

D

FCO+

FCO–

PD

WN

RBIAS

REFB

REFT

SC

LK

/DT

P

SD

IO/O

DM

SENSE

VIN

+ A

VIN + B

VIN + C

VIN

+ D

VIN

– A

VIN – B

VIN – C

VIN

– D

VREF

AV

DD

AV

DD

AV

DD

AV

DD

AV

DD

AVDD

AV

DD

AV

DD

AV

DD

AV

DD

AVDD

AVDD

DR

GN

D

DR

VD

D

RE

FE

RE

NC

ED

EC

OU

PL

ING

C20

40.

1µF

C20

30.

1µF

C20

22.

2µF

C20

10.

1µF

R20510kΩ

R203100kΩ

R204100kΩ

32 2 2 2

1J2

01

1 8730

20

18

16

14

19

17

15

13

24

23

11 12

22

21

102

25262732353639

45

46

5 6 9

31

40

43

44

2829

41

33

38

47

4

3437

48

3

42U

201

AD

9287

LF

CS

P

R20

210

0kΩ

CS

B_D

UT

13

J202

SD

IO_O

DM

13

J203

SC

LK

_DT

P3

1J2

04

DR

VD

D_D

UT

DR

VD

D_D

UT

R20

110

kΩ AVDD_DUT

CHA

CHB

CHC

CHD

CHA

CHB

CHC

DCODCO

FCO

FCO

AV

DD

_DU

T

AV

DD

_DU

T

AV

DD

_DU

T

AVDD_DUTAVDD_DUT

VSENSE_DUT

VIN

_A

VIN_B

VIN_C

VIN

_AVIN_B

VREF_DUT

AV

DD

_DU

T

AV

DD

_DU

T

CL

K

CHD

AV

DD

_DU

T

AV

DD

_DU

T

AV

DD

_DU

T

AV

DD

_DU

T

AV

DD

_DU

T

VIN

_D

VIN_C

VIN

_D

GN

DG

ND

AV

DD

_DU

T

PW

DN

EN

AB

LE

AL

WA

YS

EN

AB

LE

SP

I

DT

P E

NA

BL

E

U20

3

CW

VR

EF

= 1

V

VR

EF

= E

XT

ER

NA

L

VR

EF

= 0

.5V

RE

MO

VE

C21

4 W

HE

N U

SIN

G E

XT

ER

NA

L V

RE

F

VR

EF

= 0

.5V

(1+

R23

2/R

233)

VR

EF

SE

LE

CT

RE

FE

RE

NC

E C

IRC

UIT

C21

20.

1µF

R22

94.

99kΩ

C21

41µ

FC

213

0.1µ

F

R23

010

kΩ

R23

1D

NP

DN

P

VS

EN

SE

_DU

T

R22

847

0kΩ

DN

P

DN

P

R23

4D

NP

R23

5D

NP

R23

6D

NP

R23

70Ω

DN

P

AV

DD

_DU

T

VR

EF

_DU

T AVDD_DUT

TR

IM/N

C

V–

V+

AD

R51

01V

R23

2D

NP

R23

3D

NP

R21

70Ω R21

80Ω

R22

50Ω DN

PR

226

49.9

ΩD

NP

R22

70Ω DN

PR

238

DN

PR

239

10kΩ

C20

60.

1µF

R22

30Ω

R22

40Ω

R22

24.

02kΩ

2 3 5N

C =

NO

CO

NN

EC

T

R266100kΩ - DNP

R267100kΩ - DNP

CL

IP S

INE

OU

T (

DE

FA

UL

T)

DN

P:

DO

NO

T P

OP

UL

AT

E

OP

TIO

NA

LE

XT

RE

F

05966-016

Figure 63. Evaluation Board Schematic, DUT, VREF, Clock Inputs, and Digital Output Interface

AD9287 Data Sheet


CW

PO

WE

R D

OW

N E

NA

BL

E(0

V T

O 1

V =

DIS

AB

LE

PO

WE

R)

EXTERNAL VARIABLE GAIN DRIVE

VARIABLE GAIN CIRCUIT(0V TO 1.0V DC)

R31910kΩ

1

2 JP30

1

GND

VG

R32039kΩ

VG

AVDD_5V

HIL

O P

INH

I G

AIN

RA

NG

E =

2.2

5V T

O 5

.0V

LO

GA

IN R

AN

GE

= 0

V T

O 1

.0V

R31510kΩ

L310120nH

C3220.018µF

C3170.018µF

R316274Ω R317

274Ω

C3120.1µF

C3250.1µF

C3130.1µF

C3140.1µF

L309120nH

C31822pF

C3210.1µF

C3200.1µF

C3160.1µF

R31810kΩ

C32322pF

C3190.1µF

C3240.1µF

INH4 INH3

AV

DD

_5V

AV

DD

_5V

C32610µF

C31510µF

OP

TIO

NA

L V

GA

DR

IVE

CIR

CU

IT F

OR

CH

AN

NE

L C

AN

D C

HA

NN

EL

D

C3110.1µF

R31210kΩ

R31310kΩDNP

C303DNP

L3040Ω

R303DNP

L3080Ω

24 172023 1822 1921

R304DNP

L3060Ω

L3050Ω

L3020Ω

L3030Ω

L3070Ω

C3080.1µF

C3070.1µF

C3060.1µF

C3050.1µF

R310187Ω

R309187Ω

R308187Ω

R307187Ω

C302DNPL301

0Ω

C301DNP

R305374Ω

R306374Ω

CH

_C

CH

_D

CH

_D

CH

_C

AV

DD

_5V

AV

DD

_5V

AV

DD

_5V

C304DNP

R301DNP

R302DNP

3110

2625

1427

3 64 51 832

9

1516 VG

281329123011

2 7

COM1 COM2

ENBLENBV

GAINHILO

INH

1

INH

2

LM

D1

LM

D2

LO

N1

LO

N2LOP1 LOP2

MODEN

C

RCLMP

VCM1 VCM2VIN1 VIN2VIP1 VIP2

VO

H1

VO

H2

VO

L1

VO

L2

VP

S1

VP

S2

VP

SV

AD8332

CO

MM

CO

MM

R31110kΩDNP

R31410kΩDNP

C3100.1µF

C3091000pF

RC

LA

MP

PIN

HIL

O P

IN =

LO

= ±

50m

VH

ILO

PIN

= H

= ±

75m

VM

OD

E P

INP

OS

ITIV

E G

AIN

SL

OP

E =

0V

TO

1.0

VN

EG

AT

IVE

GA

IN S

LO

PE

= 2

.25V

TO

5.0

V

U301

POPULATE L301 TO L308 WITH0Ω RESISTORS OR DESIGNYOUR OWN FILTER.

DNP: DO NOT POPULATE

05

966-

017

Figure 64. Evaluation Board Schematic, Optional DUT Analog Input Drive and SPI Interface Circuit

Data Sheet AD9287


MODE PINPOSITIVE GAIN SLOPE = 0V TO 1.0VNEGATIVE GAIN SLOPE = 2.25V TO 5.0V

HILO PINHI GAIN RANGE = 2.25V TO 5.0VLO GAIN RANGE = 0V TO 1.0V R

414

10kΩ

L41

012

0nH

C4200.018µF

C41

50.

018µ

F

R41

527

4Ω

C41

00.

1µF

C42

50.

1µF

C42

30.

1µF

C42

40.

1µF

L40

912

0nH

C41

822

pF

C41

70.

1µF

C41

60.

1µF

C41

40.

1µF

R41

710

kΩ

C42

122

pF

C41

90.

1µF

C42

20.

1µF

INH

2IN

H1

AVDD_5V

AVDD_5V

C42

610

µF

C41

310

µF

OPTIONAL VGA DRIVE CIRCUIT FOR CHANNEL A AND CHANNEL B

C40

90.

1µF

R41

110

kΩ

R41

210

kΩD

NP

C40

3D

NP

L40

40Ω

R40

3D

NP

L40

80Ω

24

17

20

23

18

22

19

21

R40

4D

NP

L40

60Ω

L40

50Ω

L40

20Ω

L40

30Ω

L40

70Ω

C40

80.

1µF

C40

70.

1µF

C40

60.

1µF

C40

50.

1µF

R41

018

7ΩR

409

187Ω

R40

818

7ΩR

407

187Ω

C40

2D

NP

L40

10Ω

C40

1D

NP

R40

537

4Ω

R40

637

4Ω

CH_A

CH_B

CH_B

CH_A

AVDD_5V

AVDD_5V

AVDD_5V

C40

4D

NP

R40

1D

NP

R40

2D

NP

3110

2625

1427

3

6

45

1

8

3291516

VG

2813

2912

3011

2

7

CO

M1

CO

M2

EN

BL

EN

BV

GA

INH

ILO

INH1

INH2

LMD1

LMD2

LON1

LON2

LO

P1

LO

P2

MO

DE

NC

RC

LM

P

VC

M1

VC

M2

VIN

1V

IN2

VIP

1V

IP2

VOH1

VOH2

VOL1

VOL2

VPS1

VPS2

VPSV

AD

8332

U40

1

COMM

COMM

R41

310

kΩD

NP

R42

410

kΩD

NP

C41

20.

1µF

C41

110

00p

F

RCLAMP PINHILO PIN = LO = ±50mVHILO PIN = H = ±75mV

POWER DOWN ENABLE(0V TO 1V = DISABLE POWER)

R416274Ω

POPULATEL401 TOL408WITH0ΩRESISTORSORDESIGNYOUR OWNFILTER.

Y1

VC

C Y2

A2

GN

D

A1

SP

I C

IRC

UIT

RY

FR

OM

FIF

O

SD

IO_O

DM

AV

DD

_DU

T

R43

11k

Ω

R43

21k

Ω

R43

31k

Ω

AV

DD

_3.3

V

1 2 3456

NC

7WZ

07

U40

3

R42

510

kΩ

AV

DD

_DU

T

RE

SE

T/R

EP

RO

GR

AM

1 23 4

S40

1

+3.

3V =

NO

RM

AL

OP

ER

AT

ION

= A

VD

D_3

.3V

+5V

= P

RO

GR

AM

MIN

G =

AV

DD

_5V

AV

DD

_5V

AV

DD

_3.3

V J402

C42

70.

1µF

R4184.75kΩ

PIC

12F

629

R41

926

1Ω

431 2

568 7

U40

2

CR

401

GP

0G

P1

GP

2

GP

4G

P5

VD

DV

SS

MC

LR

/G

P3

RE

MO

VE

WH

EN

US

ING

OR

PR

OG

RA

MM

ING

PIC

(U

402)

R4270Ω

R4200Ω

R4280Ω

R4260Ω

SDO_CHA

SDI_CHA

SCLK_CHA

CSB1_CHA

C42

90.

1µF

SC

LK

_DT

P

CS

B_D

UT

AV

DD

_DU

T

Y1

VC

C Y2

A2

GN

D

A1

1 2 3456

U40

4R

430

10kΩ

R42

910

kΩ

NC

7WZ

16

C42

80.

1µF

PIC PROGRAMMING HEADER

MCLR/GP3

GP0

GP1

PICVCC

MCLR/GP3

GP0

GP1

PICVCC

97

5

3

1

1086

4

2

J401

E40

1

R42

10Ω

, D

NP

R42

30Ω

, D

NP

R42

20Ω

, D

NP

OPTIONAL

DN

P:

DO

NO

T P

OP

UL

AT

E

05966-018

Figure 65. Evaluation Board Schematic, Optional DUT Analog Input Drive and SPI Interface Circuit (Continued)

AD9287 Data Sheet


MO

UN

TIN

G H

OL

ES

CO

NN

EC

TE

D T

O G

RO

UN

D

H2

H3

H1

H4

P1

P2

P3

P4

P5

P6

P7

P8

OP

TIO

NA

L P

OW

ER

IN

PU

T

+5.

0V

+1.

8V

+1.

8V

+3.

3V

1 2 3 4 5 6 7 8

P50

1

3.3V

_AV

DD

5V_A

VD

D

L50

210

µH

DU

T_A

VD

D

DU

T_D

RV

DD

C50

90.

1µF

C50

810

µF

L50

310

µH

L50

110

µH

DR

VD

D_D

UT

AV

DD

_DU

T

0.1µ

FC

505

0.1µ

FC

507

C50

30.

1µF

AV

DD

_5V

10µ

FC

504

C50

210

µF

10µ

FC

506

AV

DD

_3.3

V10

µH

L50

8

DE

CO

UP

LIN

G C

AP

AC

ITO

RS

AV

DD

_3.3

V

0.1µ

FC

524

0.1µ

FC

525

C52

10.

1µF

C53

10.

1µF

C53

00.

1µF

C52

90.

1µF

C52

20.

1µF

C52

80.

1µF

C52

70.

1µF

C52

60.

1µF

0.1µ

FC

517

0.1µ

FC

516

C51

80.

1µF

C52

00.

1µF

C51

90.

1µF

C52

30.

1µF

DR

VD

D_D

UT

AV

DD

_DU

T

AV

DD

_5V

SM

DC

110F

PO

WE

R S

UP

PL

Y I

NP

UT

6V,

2V M

AX

IMU

M

1

3

2

P50

3

C50

110

µF

F50

1

D50

23A S

HO

T_R

EC

TD

O-2

14A

B

D50

1S

2A_R

EC

T2A D

O-2

14A

A

21

34

FE

R50

1

CH

OK

E_C

OIL

CR

501

R50

126

1Ω

PW

R_I

N

+

GND

INP

UT

OU

TP

UT

1

GND

INP

UT

OU

TP

UT

1

OU

TP

UT

4

OU

TP

UT

4

GND

INP

UT

GND

INP

UT

DN

P:

DO

NO

T P

OP

UL

AT

E

423

1

AD

P33

39A

KC

-5

U50

4

423

1

AD

P33

39A

KC

-3.3

U50

2

1

32 4

U50

1 AD

P33

39A

KC

-1.8

1

32 4

U50

3 AD

P33

39A

KC

-1.8

L50

510

µH

10µ

HL

504

C51

51µ

F

C51

31µ

FC

512

1µF

C51

41µ

F

PW

R_I

N

PW

R_I

N

DU

T_A

VD

D

DU

T_D

RV

DD

5V_A

VD

D

3.3V

_AV

DD

PW

R_I

N

PW

R_I

N C53

21µ

F

C53

41µ

FC

535

1µF

C53

31µ

F

L50

710

µH

L50

610

µH

OU

TP

UT

1

OU

TP

UT

1

OU

TP

UT

4

OU

TP

UT

4

05966-019

Figure 66. Evaluation Board Schematic, Power Supply Inputs

Data Sheet AD9287


0596

6-0

20

Figure 67. Evaluation Board Layout, Primary Side

AD9287 Data Sheet


059

66-0

21

Figure 68. Evaluation Board Layout, Ground Plane

Data Sheet AD9287


05

966-

022

Figure 69. Evaluation Board Layout, Power Plane

AD9287 Data Sheet


059

66-0

23

Figure 70. Evaluation Board Layout, Secondary Side (Mirrored Image)

Data Sheet AD9287


Table 17. Evaluation Board Bill of Materials (BOM)1

Item Qty. Reference Designator Device Package Value Manufacturer Manufacturer’s Part Number

1 1 AD9287LFCSP_REVA PCB PCB PCB 2 75 C101, C102, C107,

C108, C109, C114, C115, C116, C121, C122, C123, C128, C201, C203, C204, C205, C206, C210, C211, C212, C213, C216, C217, C218, C219, C220, C221, C222, C223, C224, C310, C311, C312, C313, C314, C316, C319, C320, C321, C324, C325, C409, C410, C412, C414, C416, C417, C419, C422, C423, C424, C425, C427, C428, C429, C503, C505, C507, C509, C516, C517, C518, C519, C520, C521, C522, C523, C524, C525, C526, C527, C528, C529, C530, C531

Capacitor 402 0.1 μF, ceramic, X5R, 10 V, 10% tol

Murata GRM155R71C104KA88D

3 4 C104, C111, C118, C125

Capacitor 402 2.2 pF, ceramic, COG, 0.25 pF tol, 50 V

Murata GRM1555C1H2R2GZ01B

4 4 C315, C326, C413, C426

Capacitor 805 10 μF, 6.3 V ±10% ceramic, X5R

Murata GRM219R60J106KE19D

5 1 C202 Capacitor 603 2.2 μF, ceramic, X5R, 6.3 V, 10% tol

Murata GRM188C70J225KE20D

6 2 C309, C411 Capacitor 402 1000 pF, ceramic, X7R, 25 V, 10% tol

Murata GRM155R71H102KA01D

7 4 C317, C322, C415, C420


AVX 0402YC183KAT2A

8 4 C318, C323, C418, C421

Capacitor 402 22 pF, ceramic, NPO, 5% tol, 50 V

Murata GRM1555C1H220JZ01D

9 1 C501 Capacitor 1206 10 μF, tantalum, 16 V, 20% tol

Rohm TCA1C106M8R

10 9 C214, C512, C513, C514, C515, C532, C533, C534, C535

Capacitor 603 1 μF, ceramic, X5R, 6.3 V, 10% tol

Murata GRM188R61C105KA93D

11 8 C305, C306, C307, C308, C405, C406, C407, C408


Murata GRM21BR71H104KA01L

12 4 C502, C504, C506, C508

Capacitor 603 10 μF, ceramic, X5R, 6.3 V, 20% tol

Murata GRM188R60J106M

13 1 CR201 Diode SOT-23 30 V, 20 mA, dual Schottky

Agilent Technologies

HSMS2812-TRIG

14 2 CR401, CR501 LED 603 Green, 4 V, 5 m candela

Panasonic LNJ314G8TRA

15 1 D502 Diode DO-214AB 3 A, 30 V, SMC Micro Commercial Co.

SK33-TP

16 1 D501 Diode DO-214AA 2 A, 50 V, SMC Micro Commercial Co.

S2A-TP

AD9287 Data Sheet



17 1 F501 Fuse 1210 6.0 V, 2.2 A trip-current resettable fuse

Tyco/Raychem NANOSMDC110F-2

18 1 FER501 Choke coil 2020 10 μH, 5 A, 50 V, 190 Ω @ 100 MHz

Murata DLW5BSN191SQ2L

19 12 FB101, FB102, FB103, FB104, FB105, FB106, FB107, FB108, FB109, FB110, FB111, FB112

Ferrite bead 603 10 Ω, test freq 100 MHz, 25% tol, 500 mA

Murata BLM18BA100SN1B

20 1 JP301 Connector 2-pin 100 mil header jumper, 2-pin

Samtec TSW-102-07-G-S

21 2 J205, J402 Connector 3-pin 100 mil header jumper, 3-pin

Samtec TSW-103-07-G-S

22 1 J201 to J204 Connector 12-pin 100 mil header male, 4 × 3 triple row straight

Samtec TSW-104-08-G-T

23 1 J401 Connector 10-pin 100 mil header, male, 2 × 5 double row straight

Samtec TSW-105-08-G-D

24 8 L501, L502, L503, L504, L505, L506, L507, L508

Ferrite bead 1210 10 μH, bead core 3.2 × 2.5 × 1.6 SMD, 2 A

Murata BLM31PG500SN1L

25 4 L309, L310, L409, L410 Inductor 402 120 nH, test freq 100 MHz, 5% tol, 150 mA

Murata LQG15HNR12J02B

26 16 L301, L302, L303, L304, L305, L306, L307, L308, L401, L402, L403, L404, L405, L406, L407, L408

Resistor 805 0 Ω, 1/8 W, 5% tol NIC Components

NRC10ZOTRF

27 1 OSC201 Oscillator SMT Clock oscillator, 100.00 MHz, 3.3 V

Valpey Fisher VFAC3H-L-100MHz

28 5 P101, P103, P105, P107, P201

Connector SMA Side-mount SMA for 0.063" board thickness

Johnson Components

142-0710-851

29 1 P202 Connector Header 1469169-1, right angle 2-pair, 25 mm, header assembly

Tyco 6469169-1

30 1 P503 Connector 0.1", PCMT

SC1153, power supply connector

Switchcraft RAPC722X

31 15 R201, R205, R214, R215, R221, R239, R312, R315, R318, R411, R414, R417, R425, R429, R430

Resistor 402 10 kΩ, 1/16 W, 5% tol

NIC Components

NRC04J103TRF

32 14 R103, R117, R129, R142, R216, R217, R218, R223, R224, R237, R420, R426, R427, R428

Resistor 402 0 Ω, 1/16 W, 5% tol

NIC Components

NRC04Z0TRF

33 4 R102, R115, R128, R141

Resistor 402 64.9 Ω, 1/16 W, 1% tol

NIC Components

NRC04F64R9TRF

34 4 R104, R116, R130, R143

Resistor 603 0 Ω, 1/10 W, 5% tol

NIC Components

NRC06Z0TRF

Data Sheet AD9287



35 15 R109, R111, R112, R123, R125, R126, R135, R138, R139, R148, R149, R150, R431, R432, R433

Resistor 402 1 kΩ, 1/16 W, 1% tol

NIC Components

NRC04F1001TRF

36 8 R108, R110, R121, R122, R134, R136, R146, R147

Resistor 402 33 Ω, 1/16 W, 5% tol

NIC Components

NRC04J330TRF

37 4 R161, R162, R163, R164

Resistor 402 499 Ω, 1/16 W, 1% tol

NIC Components

NRC04F4990TRF

38 3 R202, R203, R204 Resistor 402 100 kΩ, 1/16 W, 1% tol

NIC Components

NRC04F1003TRF

39 1 R222 Resistor 402 4.02 kΩ, 1/16 W, 1% tol

NIC Components

NRC04F4121TRF

40 1 R213 Resistor 402 49.9 Ω, 1/16 W, 0.5% tol

Susumu RR0510R-49R9-D


NIC Components

NRC04F4991TRF

42 2 R230, R319 Potentiometer 3-lead 10 kΩ, cermet trimmer potentiometer, 18-turn top adjust, 10%, 1/2 W

BC Components

CT94EW103

43 1 R228 Resistor 402 470 kΩ, 1/16 W, 5% tol

NIC Components

NRC04J474TRF

44 1 R320 Resistor 402 39 kΩ, 1/16 W, 5% tol

NIC Components

NRC04J393TRF

45 8 R307, R308, R309, R310, R407, R408, R409, R410

Resistor 402 187 Ω, 1/16 W, 1% tol

NIC Components

NRC04F1870TRF

46 4 R305, R306, R405, R406

Resistor 402 374 Ω, 1/16 W, 1% tol

NIC Components

NRC04F3740TRF

47 4 R316, R317, R415, R416

Resistor 402 274 Ω, 1/16 W, 1% tol

NIC Components

NRC04F2740TRF

48 11 R245, R247, R249, R251, R253, R255, R257, R259, R261, R263, R265

Resistor 201 0 Ω, 1/20 W, 5% tol Panasonic ERJ-1GE0R00C


NIC Components

NRC04J472TRF

50 1 R419 Resistor 402 261 Ω, 1/16 W, 1% tol

NIC Components

NRC04F2610TRF

51 1 R501 Resistor 603 261 Ω, 1/16 W, 1% tol

NIC Components

NRC06F2610TRF

52 2 R240, R241 Resistor 402 243 Ω, 1/16 W, 1% tol

NIC Components

NRC04F2430TRF

53 2 R242, R243 Resistor 402 100 Ω, 1/16 W, 1% tol

NIC Components

NRC04F1000TRF

54 1 S401 Switch SMD Light touch, 100GE, 5 mm

Panasonic EVQ-PLDA15

55 5 T101, T102, T103, T104, T201

Transformer CD542 ADT1-1WT, 1:1 impedance ratio transformer

Mini-Circuits ADT1-1WT+

56 2 U501, U503 IC SOT-223 ADP3339AKC-1.8, 1.5 A, 1.8 V LDO regulator

Analog Devices ADP3339AKCZ-1.8

AD9287 Data Sheet



57 2 U301, U401 IC LFCSP, CP-32

AD8332ACP, ultralow noise precision dual VGA

Analog Devices AD8332ACPZ

58 1 U504 IC SOT-223 ADP3339AKC-5 Analog Devices ADP3339AKCZ-5 59 1 U502 IC SOT-223 ADP3339AKC-3.3 Analog Devices ADP3339AKCZ-3.3 60 1 U201 IC LFCSP,

CP-48-1 AD9287BCPZ-100, quad, 8-bit, 100 MSPS serial LVDS 1.8 V ADC

Analog Devices AD9287BCPZ-100

61 1 U203 IC SOT-23 ADR510ARTZ, 1.0 V, precision low noise shunt voltage reference

Analog Devices ADR510ARTZ

62 1 U202 IC LFCSP CP-32-2

AD9515BCPZ Analog Devices AD9515BCPZ

63 1 U403 IC SC70, MAA06A

NC7WZ07 Fairchild NC7WZ07P6X_NL

64 1 U404 IC SC70, MAA06A

NC7WZ16 Fairchild NC7WZ16P6X_NL

65 1 U402 IC 8-SOIC Flash prog mem 1k × 14, RAM size 64 × 8, 20 MHz speed, PIC12F controller series

Microchip PIC12F629-I/SN

1 This BOM is RoHS compliant.

Data Sheet AD9287


OUTLINE DIMENSIONS

COMPLIANT TO JEDEC STANDARDS MO-220-WKKD

1

0.50BSC

BOTTOM VIEW

48

1324

3637

5.655.50 SQ5.35

0.450.400.35

0.800.750.70

0.05 MAX0.02 NOM

0.20 REF

COPLANARITY0.08

0.300.230.18

7.107.00 SQ6.90

0.20 MIN

5.50 REF

TOP VIEW

10-

10

-20

18-

B

END VIEW

EXPOSEDPAD

PK

G-0

03

64

1/0

04

49

9

FOR PROPER CONNECTION OFTHE EXPOSED PAD, REFER TOTHE PIN CONFIGURATION ANDFUNCTION DESCRIPTIONSSECTION OF THIS DATA SHEET.

PIN 1IN D ICATO R AR E A OP TIO NS(SEE DETAIL A)

DETAIL A(JEDEC 95)

PIN 1INDICATOR

AREA

SEATINGPLANE

Figure 71. 48-Lead Lead Frame Chip Scale Package [LFCSP]

7 mm × 7 mm Body and 0.75 mm Package Height (CP-48-9)

Dimensions shown in millimeters

ORDERING GUIDE

Model1 Notes Temperature Range Package Description

Package Option

AD9287ABCPZ-100 −40°C to +85°C 48-Lead Lead Frame Chip Scale Package [LFCSP] CP-48-9 AD9287ABCPZRL7-100 −40°C to +85°C 48-Lead Lead Frame Chip Scale Package [LFCSP] 7” Tape and Reel CP-48-9 AD9287-100EBZ 2 Evaluation Board 1 Z = RoHS Compliant Part. 2 Interposer board (HSC-ADC-FIFO5-INTZ) is required to connect to HSC-ADC-EVALCZ data capture board.

©2006–2020 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05966-11/20(G)

http://www.analog.com/hsc_adc_evalcz?doc=AD9287.pdf


Quad, 8-Bit, 100 MSPS, Serial LVDS 1.8 V ADC Data Sheet AD9287

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