EE314 Intel Pentium 4 Field Effect Field Effect Transistors Transistors Equivalent Circuits Equivalent Circuits
Nov 10, 2015
EE314Intel Pentium 4Field Effect Transistors Equivalent Circuits
Chapter 12: Field Effect TransistorsSmall-Signal Equivalent CircuitsExamplesTechnologyFuture Devices
MOSFET Transistor
Current-Voltage RelationsMOSFET TransistorNMOS transistor, 0.25mm, Ld = 10mm, W/L = 1.5, VDD = 2.5V, VT = 0.4VVDS = VGS - VTcut-off
Load-Line Analysis of NMOS AmplifierIt is a graphical analysis similar to load-line analysis of pn diode.SchematicCircuit Analysis:Input loopOutput loopLoad linevGSvDSWe look for the operating point
Load-Line Analysis of NMOS AmplifierExercise:
Draw the Load lineRD= 1 kW
Load-Line Analysis of NMOS AmplifierLoad lineTaking iD=0 or vDS=0 we find out the load lane and the quiescent operating point Q for VGS=4VThe quiescent valuesvin(t)=0 then iDQ=9 mAvGSQ=4V and vDSQ=11VPoints A & B intersection of curve and the load-line for the maximum and the minimum gate voltage
Input signalLoad-Line Analysis of NMOS Amplifier(peak-to-peak amplitude is 2V)12V peak-to-peakInverse operationThe positive peak of the input occurs at the same time as the min. value of vDS. The output is not a symmetrical sinusoid! (nonlinear distortion)vDS(t)vin(t)2V peak-to-peak
Self Bias CircuitsAnalysis of amplifier circuits is often undertaken in two steps:(1) The dc circuit analysis to determine the Q point. It involves the nonlinear equation or the load-line method. This is called bias analysisThe fixed-plus self-bias circuitExercise: Find VG voltage as a function of VDD, R1 and R2
Self Bias CircuitsAnalysis of amplifier circuits is often undertaken in two steps:(1) The dc circuit analysis to determine the Q point. It involves the nonlinear equation or the load-line method. This is called bias analysisThe fixed-plus self-bias circuit
Self Bias CircuitsAnalysis of amplifier circuits is often undertaken in two steps:(1) The dc circuit analysis to determine the Q point. It involves the nonlinear equation or the load-line method. This is called bias analysis(2) Use a linear small-signal equivalent circuit to determine circuit parametersEquivalent circuitAnalysisvGSvDSfind vGS
Self Bias CircuitsAnalysis of amplifier circuits is often undertaken in two steps:(1) The dc circuit analysis to determine the Q point. It involves the nonlinear equation or the load-line method. This is called bias analysis(2) Use a linear small-signal equivalent circuit to determine circuit parametersEquivalent circuitAnalysisvGSvDSFor saturation regionfind iD
Self Bias CircuitsAnalyze the self-bias circuit shown. The transistor has KP=50mA/V2, Vto=2V, L=10mm, and W=400mmfind vGSfind iDExercise 12.5find vDS
FlexibleField Effect TransistorsEE314
Q: How we can do this?A: A new generation of MOSFETs for plastic electronicsPlay video about plastic electronicshttp://www.plasticlogic.com
http://www.hkn.org/imgs/bridge_sp06_figure2.gifTransistor Feature Sizes
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