SIMULATION OF AMPLIFIERS USING NGSPICE

VISHNU V

2nd Year M.Tech VLSI and Embedded Systems

Govt. Model Engineering College, Thrikkakara

TECHNICAL WORKSHOP MARATHON 2012

ANALYSIS OF AMPLIFIERS USING NGSPICE

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CONSIDER THE AMPLIFIER SHOWN IN FIGURE

MODEL DESCRIPTION OF TRANSISTOR

.MODEL GENERIC NPN

Q1 C B E GENERIC

MODEL TYPEMODEL NAME

WHAT IS THE NEED OF COUPLING CAPACITORS IN AN AMPLIFIER ???

NEED OF COUPLING CAPACITORS

B

C

E

OUTPUT NODE

NEED OF COUPLING CAPACITORS

B

C

E

OUTPUT NODE

WHAT ARE THE WAVEFORMS AT BASE NODE AND COLLECTOR NODE ???

NEED OF COUPLING CAPACITORS

WAVEFORM AT BASE NODE AND COLLECTOR NODE

OUTPUT(COLLECTOR)

INPUT(BASE)

NEED OF COUPLING CAPACITORS

WAVEFORM AT BASE NODE AND OUTPUT NODE

OUTPUT

INPUT(BASE)

AFTER ADDING INPUT COUPLING CAPACITOR

B

C

E

OUTPUT NODE

INPUT VOLTAGE

VOLTAGE AT BASE NODE

VOLTAGE AT COLLECTOR NODE

OUTPUT NODE VOLTAGE

EFFECT OF BYPASS CAPACITOR

BYPASS CAPACITOR

FREQUENCY RESPONSE PLOT WITH BYPASS CAPACITOR

FREQUENCY RESPONSE PLOT WITHOUT BYPASS CAPACITOR

ANALYSE BOTH FREQUENCY RESPONSE PLOTS AND MAKE CONCLUSIONS

ANALYSIS OF BJT AMPLIFIERS

ANALYSE THE FOLLOWING CIRCUIT USING NGSPICE

PLOT THE FREQUENCY RESPONSE PLOTS FOR THE CIRCUIT WITH AND WITHOUT Rce RESISTANCE

DESIGN A COMMON EMITTER AMPLIFIER FOR THE GIVEN SPECIFICATIONS AND PLOT ITS TRANSIENT AND AC RESPONSE USING NGSPICE ??

(Use Circuit in ELECTRONIC CIRCUITS Lab)

DESIGN COMMON BASE AMPLIFIER AND COMMON COLLECTOR AMPLIFIER FOR THE GIVEN CONFIGURATIONS AND PLOT ITS TRANSIENT AND AC RESPONSE USING NGSPICE AND COMPARE THE OUTPUTS

(Use Circuit in ELECTRONIC CIRCUITS Lab)

MOS AMPLIFIERS

DIFFERENT TYPES OF MOS AMPLIFIERS

COMMON SOURCE AMPLIFIER

COMMON GATE AMPLIFIER

COMMON DRAIN AMPLIFIER

MODEL DESCRIPTION OF MOSFET

.MODEL MOS1 NMOS

M1 D G S B MOS1 W=22.0U L=0.6U

MODEL NAME MODEL TYPE

SCALING PARAMETERS

MODEL DESCRIPTION OF MOSFET CONSIDERING ALL THE PARAMETERS

.MODEL MOS1 NMOS VTO=0.7 GAMMA=0.5 LAMBDA=0.1 PHI=0.8 CGBO=0.38E-9 CGDO=0.4E-9 CGSO=0.4E-9 CJ=0.57E-3 CJSW=0.12E-9 TOX=9.5E-9 UO=460 LD=0.08E-6 JS=10E-9 MJ=0.5 MJSW=0.4 PB = 0.9

COMMON SOURCE AMPLIFIER

PLOT THE TRANSIENT RESPONSE AND FREQUENCY RESPONSE OF THE FOLLOWING AMPLIFIER USING NGSPICE

OUTPUT WAVEFORMS – TRANSIENT RESPONSE

FREQUENCY RESPONSE

FREQUENCY RESPONSE WITHOUT BYPASS(CS) CAPACITOR

DC ANALYSIS CONTROL LINE O/P CHARACTERISTICS OF MOSFET

DC VDS 0 5 0.2 VGS 1 4 1PLOT -vds#branch vs V(2)

TRANSFER CHARACTERISTICS

LAB SESSION

EXPERIMENTS

LOW PASS AND HIGH PASS FREQUENCY RESPONSE

DC ANALYSIS OF CE, CB and CC CONFIGURATIONS

PLOT TRANSIENT AND FREQUENCY RESPONE OF

- CE, CB and CC AMPLIFIERS

- CS, CG and CD AMPLIFIERS

EXPERIMENTS IN ELECTRONIC CIRCUITS LAB RECORD

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