OrCAD PSpice A/D
How to use this online manual
How to print this online manual
Welcome to OrCAD
Overview
Commands
Analog devices
Digital devices
Customizing device equations
Glossary
Reference Manual
Index

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Version 9.0, October, 1998.
Copyright 1998, OrCAD, Inc. All rights reserved.
Printed in the United States of America.
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Contents
How to Use This
Online Manual
How to print this online manual . . . . . . . . . . . . . . . . . . . . . xiv
Welcome to OrCAD . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvi
Typographical conventions . . . . . . . . . . . . . . . . . . . . . . xvi
Command syntax formats . . . . . . . . . . . . . . . . . . . . . . xvii
Numeric value conventions . . . . . . . . . . . . . . . . . . . . . xviii
Numeric expression conventions . . . . . . . . . . . . . . . . . . . xix
Command line options
for OrCAD applications . . . . . . . . . . . . . . . . . . . . . xxii
Command files . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxii
Creating and editing command files . . . . . . . . . . . . . . . xxii
Log files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxiii
Editing log files . . . . . . . . . . . . . . . . . . . . . . . . . xxiv
Simulation command line specification format . . . . . . . . . . . xxv
Simulation command line options . . . . . . . . . . . . . . . . xxvi
Specifying simulation command line options. . . . . . . . . . xxvii
Commands
Command reference
for PSpice and PSpice A/D . . . . . . . . . . . . . . . . . . . . . 30
.AC (AC analysis) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
.ALIASES, .ENDALIASES
(aliases and endaliases) . . . . . . . . . . . . . . . . . . . . . . . 33
.DC (DC analysis) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Linear sweep . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Logarithmic sweep . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Nested sweep . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
.DISTRIBUTION (user-defined distribution) . . . . . . . . . . . . . . . 37
Deriving updated parameter values . . . . . . . . . . . . . . . . . . 37
Usage example . . . . . . . . . . . . . . . . . . . . . . . . . . 38
.END (end of circuit) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
.EXTERNAL (external port) . . . . . . . . . . . . . . . . . . . . . . . . 40
.FOUR (Fourier analysis) . . . . . . . . . . . . . . . . . . . . . . . . . 41
.FUNC (function) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
.IC (initial bias point condition) . . . . . . . . . . . . . . . . . . . . . . 43
.INC (include file) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
.LIB (library file) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
.LOADBIAS (load bias point file) . . . . . . . . . . . . . . . . . . . . . 46
.MC (Monte Carlo analysis) . . . . . . . . . . . . . . . . . . . . . . . . 47
.MODEL (model definition) . . . . . . . . . . . . . . . . . . . . . . . . 50
Parameters for setting temperature . . . . . . . . . . . . . . . . . . . 53
Model parameters for device temperature . . . . . . . . . . . . 53
Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

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Contents
Special considerations. . . . . . . . . . . . . . . . . . . . . . . 54
.NODESET (set approximate node voltage for bias point) . . . . . . . . 55
.NOISE (noise analysis) . . . . . . . . . . . . . . . . . . . . . . . . . . 56
.OP (bias point) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
.OPTIONS (analysis options) . . . . . . . . . . . . . . . . . . . . . . . 59
Flag options . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Option with a name as its value . . . . . . . . . . . . . . . . . . 60
Numerical options with their default values . . . . . . . . . . . 61
PSpice A/D digital simulation condition messages . . . . . . . . . . 63
.PARAM (parameter) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
.PLOT (plot) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
.PRINT (print) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
.PROBE (Probe) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
DC Sweep and transient analysis output variables . . . . . . . . . . . 70
Multiple-terminal devices . . . . . . . . . . . . . . . . . . . . . . 71
AC analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Noise analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
.SAVEBIAS (save bias point to file) . . . . . . . . . . . . . . . . . . . . 75
Usage examples . . . . . . . . . . . . . . . . . . . . . . . . . . 76
.SENS (sensitivity analysis) . . . . . . . . . . . . . . . . . . . . . . . . 78
.STEP (parametric analysis) . . . . . . . . . . . . . . . . . . . . . . . . 79
Usage examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
.STIMLIB (stimulus library file) . . . . . . . . . . . . . . . . . . . . . . 82
.STIMULUS (stimulus) . . . . . . . . . . . . . . . . . . . . . . . . . . 83
.SUBCKT (subcircuit) . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
.ENDS (end subcircuit) . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Usage examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
.TEMP (temperature) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
.TEXT (text parameter) . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
.TF (transfer) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
.TRAN (transient analysis) . . . . . . . . . . . . . . . . . . . . . . . . . 90
.VECTOR (digital output) . . . . . . . . . . . . . . . . . . . . . . . . . 92
.WATCH (watch analysis results) . . . . . . . . . . . . . . . . . . . . . 94
.WCASE (sensitivity/worst-case analysis) . . . . . . . . . . . . . . . . . 95
* (comment) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
; (in-line comment) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
+ (line continuation) . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Differences between PSpice and Berkeley SPICE2 . . . . . . . . . . . 102
Analog devices
Analog devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Device types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Analog device summary . . . . . . . . . . . . . . . . . . . . . . . 107
GaAsFET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Capture parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Setting operating temperature . . . . . . . . . . . . . . . . . . . 111
Model parameters . . . . . . . . . . . . . . . . . . . . . . . . . . 112
GaAsFET model parameters for all levels . . . . . . . . . . . . 112
GaAsFET model parameters specific to model levels . . . . . . 113
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Contents
Auxiliary model parameters BTRK, DVT, and DVTT . . . . . . 116
GaAsFET equations . . . . . . . . . . . . . . . . . . . . . . . . . 117
GaAsFET equations for DC current: all levels . . . . . . . . . . 117
GaAsFET equations for DC current: specific to model levels . . 118
GaAsFET equations for capacitance . . . . . . . . . . . . . . . 123
GaAsFET equations for temperature effect . . . . . . . . . . . 125
GaAsFET equations for noise. . . . . . . . . . . . . . . . . . . 126
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
Capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Capture parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
Breakout parts . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
Capacitor model parameters . . . . . . . . . . . . . . . . . . . . . 130
Capacitor equations . . . . . . . . . . . . . . . . . . . . . . . . . . 130
Capacitor value formula. . . . . . . . . . . . . . . . . . . . . . 130
Capacitor equation for noise . . . . . . . . . . . . . . . . . . . 130
Diode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Capture parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
Setting operating temperature . . . . . . . . . . . . . . . . . . . 132
Diode model parameters . . . . . . . . . . . . . . . . . . . . . . . 133
Diode equations . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
Diode equations for DC current . . . . . . . . . . . . . . . . . 134
Diode equations for capacitance . . . . . . . . . . . . . . . . . 134
Diode equations for noise . . . . . . . . . . . . . . . . . . . . . 135
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
Diode equations for temperature effects . . . . . . . . . . . . . 135
Voltage-controlled voltage source . . . . . . . . . . . . . . . . . . . . 136
Voltage-controlled current source . . . . . . . . . . . . . . . . . . . . 136
Basic SPICE polynomial expressions (POLY) . . . . . . . . . . . . 138
Basic controlled source properties . . . . . . . . . . . . . . . . 138
Implementation examples . . . . . . . . . . . . . . . . . . . . . 139
Current-controlled current source . . . . . . . . . . . . . . . . . . . . 141
Current-controlled voltage source . . . . . . . . . . . . . . . . . . . . 141
Basic SPICE polynomial expressions (POLY) . . . . . . . . . . . . 141
Independent current source & stimulus . . . . . . . . . . . . . . . . . 142
Independent voltage source & stimulus . . . . . . . . . . . . . . . . . 142
Independent current source & stimulus (EXP) . . . . . . . . . . . . 144
Independent current source and stimulus
exponential waveform formulas . . . . . . . . . . . . . 144
Independent current source & stimulus (PULSE) . . . . . . . . . . 145
Independent current source and stimulus
pulse waveform formulas . . . . . . . . . . . . . . . . . 146
Independent current source & stimulus (PWL) . . . . . . . . . . . 147
Independent current source & stimulus (SFFM) . . . . . . . . . . 150
Independent current source & stimulus (SIN) . . . . . . . . . . . . 151
Independent current source and stimulus
sinusoidal waveform formulas . . . . . . . . . . . . . . 152
Junction FET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153
Capture parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154
Setting operating temperature . . . . . . . . . . . . . . . . . . . 154
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Contents
Model parameters . . . . . . . . . . . . . . . . . . . . . . . . . . 155
JFET equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
JFET equations for DC current . . . . . . . . . . . . . . . . . . 157
JFET equations for capacitance . . . . . . . . . . . . . . . . . . 158
JFET equations for temperature effects . . . . . . . . . . . . . . 159
JFET equations for noise . . . . . . . . . . . . . . . . . . . . . 159
Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
Inductor coupling (and magnetic core) . . . . . . . . . . . . . . . . . . 160
Transmission line coupling . . . . . . . . . . . . . . . . . . . . . . . . 160
Inductor coupling
. . . . . . . . . . . . . . . . . . . . . . . . 161
Capture parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163
Breakout parts . . . . . . . . . . . . . . . . . . . . . . . . . . . 163
Inductor coupling: Jiles-Atherton model . . . . . . . . . . . . . 165
Inductor coupling model parameters . . . . . . . . . . . . . . . . 165
Including air-gap effects in the inductor coupling model. . . . . 166
Getting core inductor coupling model values . . . . . . . . . . . 167
Transmission line coupling . . . . . . . . . . . . . . . . . . . . . . 167
Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168
Lossy lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169
Inductor
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
Capture parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Breakout parts . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
Inductor equations . . . . . . . . . . . . . . . . . . . . . . . . . . 173
Inductance value formula . . . . . . . . . . . . . . . . . . . . . 173
Inductor equation for noise . . . . . . . . . . . . . . . . . . . . 173
Inductor model parameters . . . . . . . . . . . . . . . . . . . . . . 173
MOSFET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
Capture parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177
Setting operating temperature . . . . . . . . . . . . . . . . . . . 177
MOSFET model parameters . . . . . . . . . . . . . . . . . . . . . 178
For all model levels . . . . . . . . . . . . . . . . . . . . . . . . 178
Model levels 1, 2, and 3 . . . . . . . . . . . . . . . . . . . . . . 178
Model level 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . 178
Model level 5 (EKV version 2.6) . . . . . . . . . . . . . . . . . 179
Model level 6 (BSIM3 version 2.0) . . . . . . . . . . . . . . . . 181
Model level 7 (BSIM3 version 3.1) . . . . . . . . . . . . . . . . 181
MOSFET model parameters . . . . . . . . . . . . . . . . . . . 184
MOSFET Equations . . . . . . . . . . . . . . . . . . . . . . . . . 198
MOSFET equations for DC current. . . . . . . . . . . . . . . . 199
MOSFET equations for capacitance . . . . . . . . . . . . . . . 200
MOSFET equations for temperature effects . . . . . . . . . . . 201
MOSFET equations for noise . . . . . . . . . . . . . . . . . . 202
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
Bipolar transistor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Capture parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
Setting operating temperature . . . . . . . . . . . . . . . . . . . 205
Bipolar transistor model parameters . . . . . . . . . . . . . . . . . 206
Distribution of the CJC capacitance . . . . . . . . . . . . . . . 208
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Contents
Bipolar transistor equations . . . . . . . . . . . . . . . . . . . . . 209
Bipolar transistor equations for DC current. . . . . . . . . . . . 210
Bipolar transistor equations for capacitance . . . . . . . . . . . 211
Bipolar transistor equations for quasi-saturation effect . . . . . 212
Bipolar transistor equations for temperature effect . . . . . . . 213
Bipolar transistor equations for noise . . . . . . . . . . . . . . 214
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
Resistor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Capture parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Breakout parts . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
Resistor model parameters . . . . . . . . . . . . . . . . . . . . . . 217
Resistor equations . . . . . . . . . . . . . . . . . . . . . . . . . . 218
Resistor value formulas . . . . . . . . . . . . . . . . . . . . . . 218
Resistor equation for noise . . . . . . . . . . . . . . . . . . . . 218
Voltage-controlled switch . . . . . . . . . . . . . . . . . . . . . . . . 219
Capture parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220
Ideal switches . . . . . . . . . . . . . . . . . . . . . . . . . . . 220
Voltage-controlled switch model parameters . . . . . . . . . . . . 220
Special considerations. . . . . . . . . . . . . . . . . . . . . . . 220
Voltage-controlled switch equations . . . . . . . . . . . . . . . . . 221
Voltage-controlled switch equations for switch resistance . . . . 222
Voltage-controlled switch equation for noise . . . . . . . . . . . 222
Transmission line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223
Ideal line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224
Lossy line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225
Capture parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226
Ideal and lossy transmission lines. . . . . . . . . . . . . . . . . 226
Coupled transmission lines . . . . . . . . . . . . . . . . . . . . 227
Simulating coupled lines . . . . . . . . . . . . . . . . . . . . . 228
Simulation considerations. . . . . . . . . . . . . . . . . . . . . 228
Transmission line model parameters . . . . . . . . . . . . . . . . . 229
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
Independent voltage source & stimulus . . . . . . . . . . . . . . . . . 231
Current-controlled switch . . . . . . . . . . . . . . . . . . . . . . . . 232
Capture parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
Ideal switches . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
Current-controlled switch model parameters . . . . . . . . . . . . . 234
Special considerations. . . . . . . . . . . . . . . . . . . . . . . 234
Current-controlled switch equations . . . . . . . . . . . . . . . . . 234
Current-controlled switch equations for switch resistance . . . . 235
Current-controlled switch equation for noise . . . . . . . . . . . 235
Subcircuit instantiation . . . . . . . . . . . . . . . . . . . . . . . . . . 236
IGBT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237
Capture parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238
Setting operating temperature . . . . . . . . . . . . . . . . . . . 238
IGBT device parameters . . . . . . . . . . . . . . . . . . . . . . . 239
IGBT model parameters . . . . . . . . . . . . . . . . . . . . . . . 240
IGBT equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
IGBT equations for DC current . . . . . . . . . . . . . . . . . . 242
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Contents
IGBT equations for capacitance . . . . . . . . . . . . . . . . . 243
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
Digital devices
Digital device summary . . . . . . . . . . . . . . . . . . . . . . . . . 246
Digital primitive summary . . . . . . . . . . . . . . . . . . . . . . . . 247
General digital primitive format . . . . . . . . . . . . . . . . . . . 250
Timing models . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
Treatment of unspecified propagation delays . . . . . . . . . . . 252
Treatment of unspecified timing constraints . . . . . . . . . . . 253
Gates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254
Standard gates . . . . . . . . . . . . . . . . . . . . . . . . . . . 255
Standard gate timing model parameters. . . . . . . . . . . . . . 257
Tristate gates . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
Tristate gate types . . . . . . . . . . . . . . . . . . . . . . . . . 259
Tristate gate timing model parameters . . . . . . . . . . . . . . 260
Bidirectional transfer gates . . . . . . . . . . . . . . . . . . . . 261
Flip-flops and latches . . . . . . . . . . . . . . . . . . . . . . . . . 264
Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264
Timing violations . . . . . . . . . . . . . . . . . . . . . . . . . 264
Edge-triggered flip-flops . . . . . . . . . . . . . . . . . . . . . 265
Edge-triggered flip-flop timing model parameters . . . . . . . . 267
Edge-triggered flip-flop truth tables DFF and JKFF
. . . . 268
Edge-triggered flip-flop truth tables DFFDE and JKFFDE. . . . 269
Gated latch . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270
Gated latch truth tables . . . . . . . . . . . . . . . . . . . . . . 272
Pullup and pulldown . . . . . . . . . . . . . . . . . . . . . . . . . 273
Delay line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274
Programmable logic array . . . . . . . . . . . . . . . . . . . . . . 275
Read only memory . . . . . . . . . . . . . . . . . . . . . . . . . . 279
Random access read-write memory . . . . . . . . . . . . . . . . . 283
Multi-bit A/D and D/A converter . . . . . . . . . . . . . . . . . . 286
Multi-bit analog-to-digital converter . . . . . . . . . . . . . . . 287
Multi-bit digital-to-analog converter . . . . . . . . . . . . . . . 289
Behavioral primitives . . . . . . . . . . . . . . . . . . . . . . . . . 291
Logic expression . . . . . . . . . . . . . . . . . . . . . . . . . 292
Pin-to-pin delay . . . . . . . . . . . . . . . . . . . . . . . . . . 295
Constraint checker . . . . . . . . . . . . . . . . . . . . . . . . 304
Stimulus devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310
Stimulus generator . . . . . . . . . . . . . . . . . . . . . . . . . . 311
Time units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 312
Stimulus generator examples . . . . . . . . . . . . . . . . . . . 313
File stimulus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317
Stimulus file format . . . . . . . . . . . . . . . . . . . . . . . . 317
Transition format . . . . . . . . . . . . . . . . . . . . . . . . . 318
File stimulus device . . . . . . . . . . . . . . . . . . . . . . . . 319
Input/output model . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
Input/output model parameters . . . . . . . . . . . . . . . . . . . 322
Digital/analog interface devices . . . . . . . . . . . . . . . . . . . . . 324
8

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Contents
Digital input (N device) . . . . . . . . . . . . . . . . . . . . . . . 324
Digital input model parameters . . . . . . . . . . . . . . . . . . 325
Digital output (O Device) . . . . . . . . . . . . . . . . . . . . . . 328
Digital output model parameters . . . . . . . . . . . . . . . . . 328
Digital model libraries . . . . . . . . . . . . . . . . . . . . . . . . . 332
7400-series TTL and CMOS library files . . . . . . . . . . . . . . 333
4000-series CMOS library . . . . . . . . . . . . . . . . . . . . . . 333
Programmable array logic devices . . . . . . . . . . . . . . . . . . 334
Customizing device equations
Introduction to Device Equations . . . . . . . . . . . . . . . . . . . . 336
Making device model changes . . . . . . . . . . . . . . . . . . . . . . 337
Changing a parameter name . . . . . . . . . . . . . . . . . . . . . 338
Giving a parameter an alias . . . . . . . . . . . . . . . . . . . . . 338
Adding a parameter . . . . . . . . . . . . . . . . . . . . . . . . . . 338
Changing the device equations . . . . . . . . . . . . . . . . . . . . 339
Functional subsections of the device source file . . . . . . . . . 340
Adding a new device . . . . . . . . . . . . . . . . . . . . . . . . . 341
Specifying new internal device structure . . . . . . . . . . . . . . . 342
Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 342
Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343
Recompiling and linking the
Device Equations option . . . . . . . . . . . . . . . . . . . . . 345
Personalizing your DLL . . . . . . . . . . . . . . . . . . . . . . . 345
Simulating with the Device Equations option . . . . . . . . . . . . . . 346
Selecting which models to use from a Device Equations DLL . . . 346
Glossary
Index
9

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Contents
10

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Document Outline

• Contents
  • How to Use This Online Manual
  • Commands
  • Analog devices
  • Digital devices
  • Customizing device equations
  • Glossary
  • Index
• How to Use This Online Manual
  • How to print this online manual
  • Welcome to OrCAD
  • Overview
    • Typographical conventions
    • Command syntax formats
    • Numeric value conventions
    • Numeric expression conventions
  • Command line options for OrCAD applications
    • Command files
    • Log files
    • Simulation command line specification format
• Commands
  • Command reference for PSpice and PSpice A/D
  • .AC(ACanalysis)
  • .ALIASES,.ENDALIASES (aliases and endaliases)
  • .DC(DCanalysis)
    • Linear sweep
    • Logarithmic sweep
    • Nested sweep
  • .DISTRIBUTION(user-defineddistribution)
    • Deriving updated parameter values
  • .END(endofcircuit)
  • .EXTERNAL(externalport)
  • .FOUR(Fourieranalysis)
  • .FUNC(function)
  • .IC(initialbiaspointcondition)
  • .INC(includefile)
  • .LIB(libraryfile)
  • .LOADBIAS(loadbiaspointfile)
  • .MC(MonteCarloanalysis)
  • .MODEL(model definition)
    • Parametersforsettingtemperature
  • .NODESET(setapproximatenode voltagefor biaspoint)
  • .NOISE(noiseanalysis)
  • .OP(biaspoint)
  • .OPTIONS(analysisoptions)
    • PSpice A/D digital simulation condition messages
  • .PARAM(parameter)
  • .PLOT(plot)
  • .PRINT(print)
  • .PROBE(Probe)
    • DC Sweep and transient analysis output variables
    • AC analysis
    • Noise analysis
  • .SAVEBIAS(savebiaspointtofile)
  • .SENS(sensitivityanalysis)
  • .STEP(parametricanalysis)
    • Usage examples
  • .STIMLIB(stimuluslibraryfile)
  • .STIMULUS(stimulus)
  • .SUBCKT (subcircuit)
  • .ENDS(end subcircuit)
    • Usage examples
  • .TEMP(temperature)
  • .TEXT(text parameter)
  • .TF(transfer)
  • .TRAN(transient analysis)
  • .VECTOR(digital output)
  • .WATCH(watch analysis results)
  • .WCASE(sensitivity/worst-case analysis)
  • *(comment)
  • ;(in-linecomment)
  • +(linecontinuation)
  • Differences between PSpice and Berkeley SPICE2
• Analog devices
  • Analog devices
  • Device types
    • Analog device summary (continued)
  • GaAsFET
    • Capture parts
    • Model parameters
    • GaAsFET equations
    • References
  • Capacitor
    • Capture parts
    • Capacitor model parameters
    • Capacitor equations
  • Diode
    • Capture parts
    • Diode model parameters
    • Diode equations
    • References
  • Voltage-controlled voltage source
  • Voltage-controlled current source
    • Basic SPICE polynomial expressions (POLY)
  • Current-controlled current source
  • Current-controlled voltage source
    • Basic SPICE polynomial expressions (POLY)
  • Independent current source & stimulus
  • Independent voltage source & stimulus
    • Independent current source & stimulus (EXP)
    • Independent current source & stimulus (PULSE)
    • Independent current source & stimulus (PWL)
    • Independent current source & stimulus (SFFM)
    • Independent current source & stimulus (SIN)
  • Junction FET
    • Capture parts
    • Model parameters
    • JFET equations
    • Reference
  • Inductor coupling (and magnetic core)
  • Transmission line coupling
    • Inductor coupling 
    • Capture parts
    • Inductor coupling model parameters
    • Transmission line coupling
    • References
  • Inductor
    • Capture parts
    • Inductor model parameters
    • Inductor equations
  • MOSFET
    • Capture parts
    • MOSFET model parameters
    • MOSFET Equations
    • References
  • Bipolar transistor
    • Capture parts
    • Bipolar transistor model parameters
    • Bipolar transistor equations
    • References
  • Resistor
    • Capture parts
    • Resistor model parameters
    • Resistor equations
  • Voltage-controlled switch
    • Capture parts
    • Voltage-controlled switch model parameters
    • Voltage-controlled switch equations
  • Transmission line
    • Ideal line 
    • Lossy line
    • Capture parts
    • Transmission line model parameters
    • References
  • Independent voltage source & stimulus
  • Current-controlled switch
    • Capture parts
    • Current-controlled switch model parameters
    • Current-controlled switch equations
  • Subcircuit instantiation
  • IGBT
    • Capture parts
    • IGBT device parameters
    • IGBT model parameters
    • IGBT equations
    • References
• Digital devices
  • Digital device summary
  • Digital primitive summary
    • General digital primitive format
    • Timing models
    • Gates
    • Flip-flops and latches
    • Pullup and pulldown
    • Delay line
    • Programmable logic array
    • Read only memory
    • Random access read-write memory
    • Multi-bit A/D and D/A converter
    • Behavioral primitives
  • Stimulus devices
    • Stimulus generator
    • File stimulus
  • Input/output model
    • Input/output model parameters (continued)
  • Digital/analog interface devices
    • Digital input (N device)
    • Digital output (O Device)
  • Digital model libraries
    • 7400-series TTL and CMOS library files
    • 4000-series CMOS library
    • Programmable array logic devices
• Customizing device equations
  • Introduction to Device Equations
  • Making device model changes
    • Changing a parameter name
    • Giving a parameter an alias
    • Adding a parameter
    • Changing the device equations
    • Adding a new device
    • Specifying new internal device structure
  • Recompiling and linking the Device Equations option
    • Personalizing your DLL
  • Simulating with the Device Equations option
    • Selecting which models to use from a Device Equations DLL
• Glossary
• Index
  • Numerics
  • A
  • B
  • C
  • D
  • E
  • F
  • G
  • H
  • I
  • J
  • K
  • L
  • M
  • N
  • O
  • P
  • Q
  • R
  • S
  • T
  • U
  • V
  • W
  • X
  • Z

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