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/**********
Copyright 1990 Regents of the University of California. All rights reserved.
Author: 1987 Gary W. Ng
Modified: 2000 AlansFixes
**********/
#include "ngspice/ngspice.h"
#include "mos3defs.h"
#include "ngspice/cktdefs.h"
#include "ngspice/iferrmsg.h"
#include "ngspice/noisedef.h"
#include "ngspice/suffix.h"
#include "ngspice/compatmode.h"
/*
* MOS3noise (mode, operation, firstModel, ckt, data, OnDens)
* This routine names and evaluates all of the noise sources
* associated with MOSFET's. It starts with the model *firstModel and
* traverses all of its insts. It then proceeds to any other models
* on the linked list. The total output noise density generated by
* all of the MOSFET's is summed with the variable "OnDens".
*/
int
MOS3noise(int mode, int operation, GENmodel * genmodel, CKTcircuit * ckt,
Ndata * data, double * OnDens) {
NOISEAN * job = (NOISEAN * ) ckt->CKTcurJob;
MOS3model * firstModel = (MOS3model * ) genmodel;
MOS3model * model;
MOS3instance * inst;
double tempOnoise;
double tempInoise;
double noizDens[MOS3NSRCS];
double lnNdens[MOS3NSRCS];
int i;
double vgs, vds, vgd, vgst, alpha, beta, Sid;
double dtemp;
/* define the names of the noise sources */
static char * MOS3nNames[MOS3NSRCS] = {
/* Note that we have to keep the order */
"_rd",
/* noise due to rd */ /* consistent with thestrchr definitions */
"_rs",
/* noise due to rs */ /* in MOS3defs.h */
"_id",
/* noise due to id */
"_1overf",
/* flicker (1/f) noise */
"" /* total transistor noise */
};
for (model = firstModel; model != NULL; model = MOS3nextModel(model)) {
for (inst = MOS3instances(model); inst != NULL; inst = MOS3nextInstance(inst)) {
switch (operation) {
case N_OPEN:
/* see if we have to to produce a summary report */
/* if so, name all the noise generators */
if (job->NStpsSm != 0) {
switch (mode) {
case N_DENS:
for (i = 0; i < MOS3NSRCS; i++) {
NOISE_ADD_OUTVAR(ckt, data, "onoise_%s%s", inst->MOS3name, MOS3nNames[i]);
}
break;
case INT_NOIZ:
for (i = 0; i < MOS3NSRCS; i++) {
NOISE_ADD_OUTVAR(ckt, data, "onoise_total_%s%s", inst->MOS3name, MOS3nNames[i]);
NOISE_ADD_OUTVAR(ckt, data, "inoise_total_%s%s", inst->MOS3name, MOS3nNames[i]);
}
break;
}
}
break;
case N_CALC:
switch (mode) {
case N_DENS:
if (inst->MOS3tempGiven)
dtemp = inst->MOS3temp - ckt->CKTtemp + (model->MOS3tnom-CONSTCtoK);
else
dtemp = inst->MOS3dtemp;
NevalSrcInstanceTemp( & noizDens[MOS3RDNOIZ], & lnNdens[MOS3RDNOIZ],
ckt, THERMNOISE, inst->MOS3dNodePrime, inst->MOS3dNode,
inst->MOS3drainConductance, dtemp);
NevalSrcInstanceTemp( & noizDens[MOS3RSNOIZ], & lnNdens[MOS3RSNOIZ],
ckt, THERMNOISE, inst->MOS3sNodePrime, inst->MOS3sNode,
inst->MOS3sourceConductance, dtemp);
if (model->MOS3nlev < 3) {
Sid = 2.0 / 3.0 * fabs(inst->MOS3gm);
} else {
vds = *(ckt->CKTstate0 + inst->MOS3vds);
vgs = *(ckt->CKTstate0 + inst->MOS3vgs);
vgd = vgs - vds;
vgst=(inst->MOS3mode==1?vgs:vgd) - model->MOS3type*inst->MOS3von;
if (vgst > 0) {
if (vgst <= (vds*inst->MOS3mode)) {
/* saturation region */
alpha = 0.0;
} else {
/* linear region */
alpha = 1.0 - (vds*inst->MOS3mode/(model->MOS3type*inst->MOS3vdsat));
}
beta = inst->MOS3tTransconductance * inst->MOS3m *
inst->MOS3w/(inst->MOS3l - 2 * model->MOS3latDiff);
Sid = 2.0 / 3.0 * beta * vgst * (1.0+alpha+alpha*alpha) / (1.0+alpha) * model->MOS3gdsnoi;
} else {
/* subthreshold region */
Sid = 0.0;
}
}
NevalSrcInstanceTemp( & noizDens[MOS3IDNOIZ], & lnNdens[MOS3IDNOIZ],
ckt, THERMNOISE, inst->MOS3dNodePrime, inst->MOS3sNodePrime,
Sid, dtemp);
NevalSrc( & noizDens[MOS3FLNOIZ], NULL, ckt,
N_GAIN, inst->MOS3dNodePrime, inst->MOS3sNodePrime,
(double) 0.0);
if (newcompat.s3) {
noizDens[MOS3FLNOIZ] *= model->MOS3fNcoef *
exp(model->MOS3fNexp *
log(MAX(fabs(inst->MOS3cd), N_MINLOG))) /
(data->freq *
(inst->MOS3w - 2 * model->MOS3widthNarrow) *
(inst->MOS3l - 2 * model->MOS3latDiff) *
model->MOS3oxideCapFactor * model->MOS3oxideCapFactor);
} else {
switch (model->MOS3nlev) {
case 0:
noizDens[MOS3FLNOIZ] *= model->MOS3fNcoef *
exp(model->MOS3fNexp *
log(MAX(fabs(inst->MOS3cd), N_MINLOG))) /
(data->freq *
(inst->MOS3l - 2 * model->MOS3latDiff) *
(inst->MOS3l - 2 * model->MOS3latDiff) *
model->MOS3oxideCapFactor);
break;
case 1:
noizDens[MOS3FLNOIZ] *= model->MOS3fNcoef *
exp(model->MOS3fNexp *
log(MAX(fabs(inst->MOS3cd), N_MINLOG))) /
(data->freq *
(inst->MOS3w - 2 * model->MOS3widthNarrow) *
(inst->MOS3l - 2 * model->MOS3latDiff) *
model->MOS3oxideCapFactor);
break;
case 2: case 3:
noizDens[MOS3FLNOIZ] *= model->MOS3fNcoef *
inst->MOS3gm * inst->MOS3gm /
(pow(data->freq, model->MOS3fNexp) *
(inst->MOS3w - 2 * model->MOS3widthNarrow) *
(inst->MOS3l - 2 * model->MOS3latDiff) *
model->MOS3oxideCapFactor);
break;
}
}
lnNdens[MOS3FLNOIZ] =
log(MAX(noizDens[MOS3FLNOIZ], N_MINLOG));
noizDens[MOS3TOTNOIZ] = noizDens[MOS3RDNOIZ] +
noizDens[MOS3RSNOIZ] +
noizDens[MOS3IDNOIZ] +
noizDens[MOS3FLNOIZ];
lnNdens[MOS3TOTNOIZ] =
log(MAX(noizDens[MOS3TOTNOIZ], N_MINLOG));
* OnDens += noizDens[MOS3TOTNOIZ];
if (data->delFreq == 0.0) {
/* if we haven't done any previous integration, we need to */
/* initialize our "history" variables */
for (i = 0; i < MOS3NSRCS; i++) {
inst->MOS3nVar[LNLSTDENS][i] = lnNdens[i];
}
/* clear out our integration variables if it's the first pass */
if (data->freq == job->NstartFreq) {
for (i = 0; i < MOS3NSRCS; i++) {
inst->MOS3nVar[OUTNOIZ][i] = 0.0;
inst->MOS3nVar[INNOIZ][i] = 0.0;
}
}
} else {
/* data->delFreq != 0.0 (we have to integrate) */
for (i = 0; i < MOS3NSRCS; i++) {
if (i != MOS3TOTNOIZ) {
tempOnoise = Nintegrate(noizDens[i], lnNdens[i],
inst->MOS3nVar[LNLSTDENS][i], data);
tempInoise = Nintegrate(noizDens[i] * data->GainSqInv,
lnNdens[i] + data->lnGainInv,
inst->MOS3nVar[LNLSTDENS][i] + data->lnGainInv,
data);
inst->MOS3nVar[LNLSTDENS][i] = lnNdens[i];
data->outNoiz += tempOnoise;
data->inNoise += tempInoise;
if (job->NStpsSm != 0) {
inst->MOS3nVar[OUTNOIZ][i] += tempOnoise;
inst->MOS3nVar[OUTNOIZ][MOS3TOTNOIZ] += tempOnoise;
inst->MOS3nVar[INNOIZ][i] += tempInoise;
inst->MOS3nVar[INNOIZ][MOS3TOTNOIZ] += tempInoise;
}
}
}
}
if (data->prtSummary) {
for (i = 0; i < MOS3NSRCS; i++) {
/* print a summary report */
data->outpVector[data->outNumber++] = noizDens[i];
}
}
break;
case INT_NOIZ:
/* already calculated, just output */
if (job->NStpsSm != 0) {
for (i = 0; i < MOS3NSRCS; i++) {
data->outpVector[data->outNumber++] = inst->MOS3nVar[OUTNOIZ][i];
data->outpVector[data->outNumber++] = inst->MOS3nVar[INNOIZ][i];
}
} /* if */
break;
} /* switch (mode) */
break;
case N_CLOSE:
return (OK); /* do nothing, the main calling routine will close */
break; /* the plots */
} /* switch (operation) */
} /* for inst */
} /* for model */
return (OK);
}