ngspice/src/spicelib/devices/bjt/bjtnoise.c

230 lines
7.0 KiB
C

/**********
Copyright 1990 Regents of the University of California. All rights reserved.
Author: 1987 Gary W. Ng
**********/
#include "ngspice.h"
#include "bjtdefs.h"
#include "cktdefs.h"
#include "iferrmsg.h"
#include "noisedef.h"
#include "suffix.h"
/*
* BJTnoise (mode, operation, firstModel, ckt, data, OnDens)
*
* This routine names and evaluates all of the noise sources
* associated with BJT'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 BJT's is summed with the variable "OnDens".
*/
extern void NevalSrc();
extern double Nintegrate();
int
BJTnoise (int mode, int operation, GENmodel *genmodel, CKTcircuit *ckt,
Ndata *data, double *OnDens)
{
BJTmodel *firstModel = (BJTmodel *) genmodel;
BJTmodel *model;
BJTinstance *inst;
char name[N_MXVLNTH];
double tempOnoise;
double tempInoise;
double noizDens[BJTNSRCS];
double lnNdens[BJTNSRCS];
int i;
/* define the names of the noise sources */
static char *BJTnNames[BJTNSRCS] = {
/* Note that we have to keep the order consistent with the
strchr definitions in BJTdefs.h */
"_rc", /* noise due to rc */
"_rb", /* noise due to rb */
"_re", /* noise due to re */
"_ic", /* noise due to ic */
"_ib", /* noise due to ib */
"_1overf", /* flicker (1/f) noise */
"" /* total transistor noise */
};
for (model=firstModel; model != NULL; model=model->BJTnextModel) {
for (inst=model->BJTinstances; inst != NULL;
inst=inst->BJTnextInstance) {
if (inst->BJTowner != ARCHme) continue;
switch (operation) {
case N_OPEN:
/* see if we have to to produce a summary report */
/* if so, name all the noise generators */
if (((NOISEAN*)ckt->CKTcurJob)->NStpsSm != 0) {
switch (mode) {
case N_DENS:
for (i=0; i < BJTNSRCS; i++) {
(void)sprintf(name,"onoise_%s%s",
inst->BJTname,BJTnNames[i]);
data->namelist = (IFuid *)
trealloc((char *)data->namelist,
(data->numPlots + 1)*sizeof(IFuid));
if (!data->namelist) return(E_NOMEM);
(*(SPfrontEnd->IFnewUid))(ckt,
&(data->namelist[data->numPlots++]),
(IFuid)NULL,name,UID_OTHER,(void **)NULL);
/* we've added one more plot */
}
break;
case INT_NOIZ:
for (i=0; i < BJTNSRCS; i++) {
(void)sprintf(name,"onoise_total_%s%s",
inst->BJTname,BJTnNames[i]);
data->namelist = (IFuid *)
trealloc((char *)data->namelist,
(data->numPlots + 1)*sizeof(IFuid));
if (!data->namelist) return(E_NOMEM);
(*(SPfrontEnd->IFnewUid))(ckt,
&(data->namelist[data->numPlots++]),
(IFuid)NULL,name,UID_OTHER,(void **)NULL);
/* we've added one more plot */
(void)sprintf(name,"inoise_total_%s%s",
inst->BJTname,BJTnNames[i]);
data->namelist = (IFuid *)trealloc((char *)data->namelist,(data->numPlots + 1)*sizeof(IFuid));
if (!data->namelist) return(E_NOMEM);
(*(SPfrontEnd->IFnewUid))(ckt,
&(data->namelist[data->numPlots++]),
(IFuid)NULL,name,UID_OTHER,(void **)NULL);
/* we've added one more plot */
}
break;
}
}
break;
case N_CALC:
switch (mode) {
case N_DENS:
NevalSrc(&noizDens[BJTRCNOIZ],&lnNdens[BJTRCNOIZ],
ckt,THERMNOISE,inst->BJTcolPrimeNode,inst->BJTcolNode,
model->BJTcollectorConduct * inst->BJTarea * inst->BJTm);
NevalSrc(&noizDens[BJTRBNOIZ],&lnNdens[BJTRBNOIZ],
ckt,THERMNOISE,inst->BJTbasePrimeNode,inst->BJTbaseNode,
*(ckt->CKTstate0 + inst->BJTgx) * inst->BJTm);
NevalSrc(&noizDens[BJT_RE_NOISE],&lnNdens[BJT_RE_NOISE],
ckt,THERMNOISE,inst->BJTemitPrimeNode,inst->BJTemitNode,
model->BJTemitterConduct * inst->BJTarea * inst-> BJTm);
NevalSrc(&noizDens[BJTICNOIZ],&lnNdens[BJTICNOIZ],
ckt,SHOTNOISE,inst->BJTcolPrimeNode, inst->BJTemitPrimeNode,
*(ckt->CKTstate0 + inst->BJTcc) * inst->BJTm);
NevalSrc(&noizDens[BJTIBNOIZ],&lnNdens[BJTIBNOIZ],
ckt,SHOTNOISE,inst->BJTbasePrimeNode, inst->BJTemitPrimeNode,
*(ckt->CKTstate0 + inst->BJTcb) * inst->BJTm);
NevalSrc(&noizDens[BJTFLNOIZ],(double*)NULL,ckt,
N_GAIN,inst->BJTbasePrimeNode, inst->BJTemitPrimeNode,
(double)0.0);
noizDens[BJTFLNOIZ] *= inst->BJTm * model->BJTfNcoef *
exp(model->BJTfNexp *
log(MAX(fabs(*(ckt->CKTstate0 + inst->BJTcb)),N_MINLOG))) /
data->freq;
lnNdens[BJTFLNOIZ] =
log(MAX(noizDens[BJTFLNOIZ],N_MINLOG));
noizDens[BJTTOTNOIZ] = noizDens[BJTRCNOIZ] +
noizDens[BJTRBNOIZ] +
noizDens[BJT_RE_NOISE] +
noizDens[BJTICNOIZ] +
noizDens[BJTIBNOIZ] +
noizDens[BJTFLNOIZ];
lnNdens[BJTTOTNOIZ] =
log(noizDens[BJTTOTNOIZ]);
*OnDens += noizDens[BJTTOTNOIZ];
if (data->delFreq == 0.0) {
/* if we haven't done any previous integration, we need to */
/* initialize our "history" variables */
for (i=0; i < BJTNSRCS; i++) {
inst->BJTnVar[LNLSTDENS][i] = lnNdens[i];
}
/* clear out our integration variables if it's the first pass */
if (data->freq == ((NOISEAN*)ckt->CKTcurJob)->NstartFreq) {
for (i=0; i < BJTNSRCS; i++) {
inst->BJTnVar[OUTNOIZ][i] = 0.0;
inst->BJTnVar[INNOIZ][i] = 0.0;
}
}
} else { /* data->delFreq != 0.0 (we have to integrate) */
/* In order to get the best curve fit, we have to integrate each component separately */
for (i=0; i < BJTNSRCS; i++) {
if (i != BJTTOTNOIZ) {
tempOnoise = Nintegrate(noizDens[i], lnNdens[i],
inst->BJTnVar[LNLSTDENS][i], data);
tempInoise = Nintegrate(noizDens[i] * data->GainSqInv ,
lnNdens[i] + data->lnGainInv,
inst->BJTnVar[LNLSTDENS][i] + data->lnGainInv,
data);
inst->BJTnVar[LNLSTDENS][i] = lnNdens[i];
data->outNoiz += tempOnoise;
data->inNoise += tempInoise;
if (((NOISEAN*)ckt->CKTcurJob)->NStpsSm != 0) {
inst->BJTnVar[OUTNOIZ][i] += tempOnoise;
inst->BJTnVar[OUTNOIZ][BJTTOTNOIZ] += tempOnoise;
inst->BJTnVar[INNOIZ][i] += tempInoise;
inst->BJTnVar[INNOIZ][BJTTOTNOIZ] += tempInoise;
}
}
}
}
if (data->prtSummary) {
for (i=0; i < BJTNSRCS; i++) { /* print a summary report */
data->outpVector[data->outNumber++] = noizDens[i];
}
}
break;
case INT_NOIZ: /* already calculated, just output */
if (((NOISEAN*)ckt->CKTcurJob)->NStpsSm != 0) {
for (i=0; i < BJTNSRCS; i++) {
data->outpVector[data->outNumber++] = inst->BJTnVar[OUTNOIZ][i];
data->outpVector[data->outNumber++] = inst->BJTnVar[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);
}