/********** Copyright 1999 Regents of the University of California. All rights reserved. Author: Weidong Liu and Pin Su Feb 1999 Author: 1998 Samuel Fung, Dennis Sinitsky and Stephen Tang File: b3soifdnoi.c 98/5/01 Modified by Paolo Nenzi 2002 **********/ /* * Revision 2.1 99/9/27 Pin Su * BSIMFD2.1 release */ #include "ngspice/ngspice.h" #include "b3soifddef.h" #include "ngspice/cktdefs.h" #include "ngspice/iferrmsg.h" #include "ngspice/noisedef.h" #include "ngspice/suffix.h" #include "ngspice/const.h" /* jwan */ /* * B3SOIFDnoise (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". */ /* Channel thermal and flicker noises are calculated based on the value of model->B3SOIFDnoiMod. If model->B3SOIFDnoiMod = 1, Channel thermal noise = SPICE2 model Flicker noise = SPICE2 model If model->B3SOIFDnoiMod = 2, Channel thermal noise = B3SOIFD model Flicker noise = B3SOIFD model If model->B3SOIFDnoiMod = 3, Channel thermal noise = SPICE2 model Flicker noise = B3SOIFD model If model->B3SOIFDnoiMod = 4, Channel thermal noise = B3SOIFD model Flicker noise = SPICE2 model */ static double B3SOIFDStrongInversionNoiseEval(double vgs, double vds, B3SOIFDmodel *model, B3SOIFDinstance *here, double freq, double temp) { struct b3soifdSizeDependParam *pParam; double cd, esat, DelClm, EffFreq, N0, Nl, Vgst; double T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, Ssi; pParam = here->pParam; cd = fabs(here->B3SOIFDcd) * here->B3SOIFDm; if (vds > here->B3SOIFDvdsat) { esat = 2.0 * pParam->B3SOIFDvsattemp / here->B3SOIFDueff; T0 = ((((vds - here->B3SOIFDvdsat) / pParam->B3SOIFDlitl) + model->B3SOIFDem) / esat); DelClm = pParam->B3SOIFDlitl * log (MAX(T0, N_MINLOG)); } else DelClm = 0.0; EffFreq = pow(freq, model->B3SOIFDef); T1 = CHARGE * CHARGE * 8.62e-5 * cd * temp * here->B3SOIFDueff; T2 = 1.0e8 * EffFreq * model->B3SOIFDcox * pParam->B3SOIFDleff * pParam->B3SOIFDleff; Vgst = vgs - here->B3SOIFDvon; N0 = model->B3SOIFDcox * Vgst / CHARGE; if (N0 < 0.0) N0 = 0.0; Nl = model->B3SOIFDcox * (Vgst - MIN(vds, here->B3SOIFDvdsat)) / CHARGE; if (Nl < 0.0) Nl = 0.0; T3 = model->B3SOIFDoxideTrapDensityA * log(MAX(((N0 + 2.0e14) / (Nl + 2.0e14)), N_MINLOG)); T4 = model->B3SOIFDoxideTrapDensityB * (N0 - Nl); T5 = model->B3SOIFDoxideTrapDensityC * 0.5 * (N0 * N0 - Nl * Nl); T6 = 8.62e-5 * temp * cd * cd; T7 = 1.0e8 * EffFreq * pParam->B3SOIFDleff * pParam->B3SOIFDleff * pParam->B3SOIFDweff * here->B3SOIFDm; T8 = model->B3SOIFDoxideTrapDensityA + model->B3SOIFDoxideTrapDensityB * Nl + model->B3SOIFDoxideTrapDensityC * Nl * Nl; T9 = (Nl + 2.0e14) * (Nl + 2.0e14); Ssi = T1 / T2 * (T3 + T4 + T5) + T6 / T7 * DelClm * T8 / T9; return Ssi; } int B3SOIFDnoise (int mode, int operation, GENmodel *inModel, CKTcircuit *ckt, Ndata *data, double *OnDens) { NOISEAN *job = (NOISEAN *) ckt->CKTcurJob; B3SOIFDmodel *model = (B3SOIFDmodel *)inModel; B3SOIFDinstance *here; struct b3soifdSizeDependParam *pParam; char name[N_MXVLNTH]; double tempOnoise; double tempInoise; double noizDens[B3SOIFDNSRCS]; double lnNdens[B3SOIFDNSRCS]; double vgs, vds, Slimit; double T1, T10, T11; double Ssi, Swi; int i; /* define the names of the noise sources */ static char *B3SOIFDnNames[B3SOIFDNSRCS] = { /* Note that we have to keep the order */ ".rd", /* noise due to rd */ /* consistent with the index definitions */ ".rs", /* noise due to rs */ /* in B3SOIFDdefs.h */ ".id", /* noise due to id */ ".1overf", /* flicker (1/f) noise */ ".fb", /* noise due to floating body */ "" /* total transistor noise */ }; for (; model != NULL; model = model->B3SOIFDnextModel) { for (here = model->B3SOIFDinstances; here != NULL; here = here->B3SOIFDnextInstance) { pParam = here->pParam; 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 < B3SOIFDNSRCS; i++) { (void) sprintf(name, "onoise.%s%s", here->B3SOIFDname, B3SOIFDnNames[i]); data->namelist = TREALLOC(IFuid, data->namelist, data->numPlots + 1); if (!data->namelist) return(E_NOMEM); SPfrontEnd->IFnewUid (ckt, &(data->namelist[data->numPlots++]), NULL, name, UID_OTHER, NULL); /* we've added one more plot */ } break; case INT_NOIZ: for (i = 0; i < B3SOIFDNSRCS; i++) { (void) sprintf(name, "onoise_total.%s%s", here->B3SOIFDname, B3SOIFDnNames[i]); data->namelist = TREALLOC(IFuid, data->namelist, data->numPlots + 1); if (!data->namelist) return(E_NOMEM); SPfrontEnd->IFnewUid (ckt, &(data->namelist[data->numPlots++]), NULL, name, UID_OTHER, NULL); /* we've added one more plot */ (void) sprintf(name, "inoise_total.%s%s", here->B3SOIFDname, B3SOIFDnNames[i]); data->namelist = TREALLOC(IFuid, data->namelist, data->numPlots + 1); if (!data->namelist) return(E_NOMEM); SPfrontEnd->IFnewUid (ckt, &(data->namelist[data->numPlots++]), NULL, name, UID_OTHER, NULL); /* we've added one more plot */ } break; } } break; case N_CALC: switch (mode) { case N_DENS: NevalSrc(&noizDens[B3SOIFDRDNOIZ], &lnNdens[B3SOIFDRDNOIZ], ckt, THERMNOISE, here->B3SOIFDdNodePrime, here->B3SOIFDdNode, here->B3SOIFDdrainConductance * here->B3SOIFDm); NevalSrc(&noizDens[B3SOIFDRSNOIZ], &lnNdens[B3SOIFDRSNOIZ], ckt, THERMNOISE, here->B3SOIFDsNodePrime, here->B3SOIFDsNode, here->B3SOIFDsourceConductance * here->B3SOIFDm); switch( model->B3SOIFDnoiMod ) { case 1: case 3: NevalSrc(&noizDens[B3SOIFDIDNOIZ], &lnNdens[B3SOIFDIDNOIZ], ckt, THERMNOISE, here->B3SOIFDdNodePrime, here->B3SOIFDsNodePrime, (2.0 / 3.0 * fabs(here->B3SOIFDm * (here->B3SOIFDgm + here->B3SOIFDgds + here->B3SOIFDgmbs)))); break; case 2: case 4: NevalSrc(&noizDens[B3SOIFDIDNOIZ], &lnNdens[B3SOIFDIDNOIZ], ckt, THERMNOISE, here->B3SOIFDdNodePrime, here->B3SOIFDsNodePrime, (here->B3SOIFDueff * fabs((here->B3SOIFDqinv * here->B3SOIFDm) / (pParam->B3SOIFDleff * pParam->B3SOIFDleff)))); break; } NevalSrc(&noizDens[B3SOIFDFLNOIZ], NULL, ckt, N_GAIN, here->B3SOIFDdNodePrime, here->B3SOIFDsNodePrime, (double) 0.0); switch( model->B3SOIFDnoiMod ) { case 1: case 4: noizDens[B3SOIFDFLNOIZ] *= model->B3SOIFDkf * exp(model->B3SOIFDaf * log(MAX(fabs(here->B3SOIFDcd * here->B3SOIFDm), N_MINLOG))) / (pow(data->freq, model->B3SOIFDef) * pParam->B3SOIFDleff * pParam->B3SOIFDleff * model->B3SOIFDcox); break; case 2: case 3: vgs = *(ckt->CKTstates[0] + here->B3SOIFDvgs); vds = *(ckt->CKTstates[0] + here->B3SOIFDvds); if (vds < 0.0) { vds = -vds; vgs = vgs + vds; } if (vgs >= here->B3SOIFDvon + 0.1) { Ssi = B3SOIFDStrongInversionNoiseEval(vgs, vds, model, here, data->freq, ckt->CKTtemp); noizDens[B3SOIFDFLNOIZ] *= Ssi; } else { pParam = here->pParam; T10 = model->B3SOIFDoxideTrapDensityA * 8.62e-5 * ckt->CKTtemp; T11 = pParam->B3SOIFDweff * here->B3SOIFDm * pParam->B3SOIFDleff * pow(data->freq, model->B3SOIFDef) * 4.0e36; Swi = T10 / T11 * here->B3SOIFDcd * here->B3SOIFDm * here->B3SOIFDcd * here->B3SOIFDm; Slimit = B3SOIFDStrongInversionNoiseEval( here->B3SOIFDvon + 0.1, vds, model, here, data->freq, ckt->CKTtemp); T1 = Swi + Slimit; if (T1 > 0.0) noizDens[B3SOIFDFLNOIZ] *= (Slimit * Swi) / T1; else noizDens[B3SOIFDFLNOIZ] *= 0.0; } break; } lnNdens[B3SOIFDFLNOIZ] = log(MAX(noizDens[B3SOIFDFLNOIZ], N_MINLOG)); /* Low frequency excess noise due to FBE */ noizDens[B3SOIFDFBNOIZ] = 0.0; noizDens[B3SOIFDTOTNOIZ] = noizDens[B3SOIFDRDNOIZ] + noizDens[B3SOIFDRSNOIZ] + noizDens[B3SOIFDIDNOIZ] + noizDens[B3SOIFDFLNOIZ] + noizDens[B3SOIFDFBNOIZ]; lnNdens[B3SOIFDTOTNOIZ] = log(MAX(noizDens[B3SOIFDTOTNOIZ], N_MINLOG)); *OnDens += noizDens[B3SOIFDTOTNOIZ]; if (data->delFreq == 0.0) { /* if we haven't done any previous integration, we need to initialize our "history" variables. */ for (i = 0; i < B3SOIFDNSRCS; i++) { here->B3SOIFDnVar[LNLSTDENS][i] = lnNdens[i]; } /* clear out our integration variables if it's the first pass */ if (data->freq == job->NstartFreq) { for (i = 0; i < B3SOIFDNSRCS; i++) { here->B3SOIFDnVar[OUTNOIZ][i] = 0.0; here->B3SOIFDnVar[INNOIZ][i] = 0.0; } } } else { /* data->delFreq != 0.0, we have to integrate. */ for (i = 0; i < B3SOIFDNSRCS; i++) { if (i != B3SOIFDTOTNOIZ) { tempOnoise = Nintegrate(noizDens[i], lnNdens[i], here->B3SOIFDnVar[LNLSTDENS][i], data); tempInoise = Nintegrate(noizDens[i] * data->GainSqInv, lnNdens[i] + data->lnGainInv, here->B3SOIFDnVar[LNLSTDENS][i] + data->lnGainInv, data); here->B3SOIFDnVar[LNLSTDENS][i] = lnNdens[i]; data->outNoiz += tempOnoise; data->inNoise += tempInoise; if (job->NStpsSm != 0) { here->B3SOIFDnVar[OUTNOIZ][i] += tempOnoise; here->B3SOIFDnVar[OUTNOIZ][B3SOIFDTOTNOIZ] += tempOnoise; here->B3SOIFDnVar[INNOIZ][i] += tempInoise; here->B3SOIFDnVar[INNOIZ][B3SOIFDTOTNOIZ] += tempInoise; } } } } if (data->prtSummary) { for (i = 0; i < B3SOIFDNSRCS; 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 < B3SOIFDNSRCS; i++) { data->outpVector[data->outNumber++] = here->B3SOIFDnVar[OUTNOIZ][i]; data->outpVector[data->outNumber++] = here->B3SOIFDnVar[INNOIZ][i]; } } break; } break; case N_CLOSE: /* do nothing, the main calling routine will close */ return (OK); break; /* the plots */ } /* switch (operation) */ } /* for here */ } /* for model */ return(OK); }