sidewall capacitance calculation removed

src/spicelib/devices/vdmos/vdmos.c

@@ -121,8 +121,6 @@ IFparm VDMOSmPTable[] = { /* model parameters */
  IOPA("cbd",  VDMOS_MOD_CBD,   IF_REAL,   "B-D junction capacitance"),
  IOPA("cbs",  VDMOS_MOD_CBS,   IF_REAL,   "B-S junction capacitance"),
  IOPA("cj",   VDMOS_MOD_CJ,    IF_REAL,   "Bottom junction cap per area"),
- IOPA("cjsw", VDMOS_MOD_CJSW,  IF_REAL,   "Side junction cap per area"),
- IOP("mjsw",  VDMOS_MOD_MJSW,  IF_REAL,   "Side grading coefficient"),
  IOP("js",    VDMOS_MOD_JS,    IF_REAL,   "Bulk jct. sat. current density"),
  IOP("tox",   VDMOS_MOD_TOX,   IF_REAL,   "Oxide thickness"),
  IOP("u0",    VDMOS_MOD_U0,    IF_REAL,   "Surface mobility"),

src/spicelib/devices/vdmos/vdmosdefs.h

@@ -65,7 +65,6 @@ typedef struct sVDMOSinstance {
     double VDMOStCbd;                /* temperature corrected B-D Capacitance */
     double VDMOStCbs;                /* temperature corrected B-S Capacitance */
     double VDMOStCj;         /* temperature corrected Bulk bottom Capacitance */
-    double VDMOStCjsw;       /* temperature corrected Bulk side Capacitance */
     double VDMOStBulkPot;    /* temperature corrected Bulk potential */
     double VDMOStDepCap;     /* temperature adjusted transition point in */
                             /* the cureve matching Fc * Vj */
@@ -300,10 +299,8 @@ typedef struct sVDMOSmodel {       /* model structure for a resistor */
     double VDMOScapBD;   /* input - use tCbd */
     double VDMOScapBS;   /* input - use tCbs */
     double VDMOSbulkCapFactor;   /* input - use tCj */
-    double VDMOSsideWallCapFactor;   /* input - use tCjsw */
     double VDMOSbulkJctPotential;    /* input - use tBulkPot */
     double VDMOSbulkJctBotGradingCoeff;
-    double VDMOSbulkJctSideGradingCoeff;
     double VDMOSfwdCapDepCoeff;
     double VDMOSphi; /* input - use tPhi */
     double VDMOSgamma;
@@ -331,10 +328,8 @@ typedef struct sVDMOSmodel {       /* model structure for a resistor */
     unsigned VDMOScapBDGiven :1;
     unsigned VDMOScapBSGiven :1;
     unsigned VDMOSbulkCapFactorGiven :1;
-    unsigned VDMOSsideWallCapFactorGiven   :1;
     unsigned VDMOSbulkJctPotentialGiven  :1;
     unsigned VDMOSbulkJctBotGradingCoeffGiven    :1;
-    unsigned VDMOSbulkJctSideGradingCoeffGiven   :1;
     unsigned VDMOSfwdCapDepCoeffGiven    :1;
     unsigned VDMOSphiGiven   :1;
     unsigned VDMOSgammaGiven :1;
@@ -394,8 +389,6 @@ enum {
     VDMOS_MOD_VJ,
     VDMOS_MOD_CJ,
     VDMOS_MOD_MJ,
-    VDMOS_MOD_CJSW,
-    VDMOS_MOD_MJSW,
     VDMOS_MOD_JS,
     VDMOS_MOD_TOX,
     VDMOS_MOD_U0,

src/spicelib/devices/vdmos/vdmosdset.c

@@ -285,118 +285,6 @@ VDMOSdSetup(GENmodel *inModel, CKTcircuit *ckt)
                  *
                  *.. bulk-drain and bulk-source depletion capacitances
                  */
-                    if (vbs < here->VDMOStDepCap){
-                        arg=1-vbs/here->VDMOStBulkPot;
-                        /*
-                         * the following block looks somewhat long and messy,
-                         * but since most users use the default grading
-                         * coefficients of .5, and sqrt is MUCH faster than an
-                         * exp(log()) we use this special case code to buy time.
-                         * (as much as 10% of total job time!)
-                         */
-                        if(model->VDMOSbulkJctBotGradingCoeff ==
-                                model->VDMOSbulkJctSideGradingCoeff) {
-                            if(model->VDMOSbulkJctBotGradingCoeff == .5) {
-                                sarg = sargsw = 1/sqrt(arg);
-                            } else {
-                                sarg = sargsw =
-                                        exp(-model->VDMOSbulkJctBotGradingCoeff*
-                                        log(arg));
-                            }
-                        } else {
-                            if(model->VDMOSbulkJctBotGradingCoeff == .5) {
-                                sarg = 1/sqrt(arg);
-                            } else {
-                                sarg = exp(-model->VDMOSbulkJctBotGradingCoeff*
-                                        log(arg));
-                            }
-                            if(model->VDMOSbulkJctSideGradingCoeff == .5) {
-                                sargsw = 1/sqrt(arg);
-                            } else {
-                                sargsw =exp(-model->VDMOSbulkJctSideGradingCoeff*
-                                        log(arg));
-                            }
-                        }
-		    /*
-		    lcapbs=here->VDMOSCbs*sarg+
-                                here->VDMOSCbssw*sargsw;
-				*/
-		    lcapbs2 = model->VDMOStype*0.5/here->VDMOStBulkPot*(
-			here->VDMOSCbs*model->VDMOSbulkJctBotGradingCoeff*
-			sarg/arg + here->VDMOSCbssw*
-			model->VDMOSbulkJctSideGradingCoeff*sargsw/arg);
-		    lcapbs3 = here->VDMOSCbs*sarg*
-			model->VDMOSbulkJctBotGradingCoeff*
-			(model->VDMOSbulkJctBotGradingCoeff+1);
-		    lcapbs3 += here->VDMOSCbssw*sargsw*
-			model->VDMOSbulkJctSideGradingCoeff*
-			(model->VDMOSbulkJctSideGradingCoeff+1);
-		    lcapbs3 = lcapbs3/(6*here->VDMOStBulkPot*
-			here->VDMOStBulkPot*arg*arg);
-                    } else {
-                    /*    *(ckt->CKTstate0 + here->VDMOSqbs)= here->VDMOSf4s +
-                                vbs*(here->VDMOSf2s+vbs*(here->VDMOSf3s/2));*/
-			/*
-                        lcapbs=here->VDMOSf2s+here->VDMOSf3s*vbs;
-			*/
-			lcapbs2 = 0.5*here->VDMOSf3s;
-			lcapbs3 = 0;
-                    }
-                    if (vbd < here->VDMOStDepCap) {
-                        arg=1-vbd/here->VDMOStBulkPot;
-                        /*
-                         * the following block looks somewhat long and messy,
-                         * but since most users use the default grading
-                         * coefficients of .5, and sqrt is MUCH faster than an
-                         * exp(log()) we use this special case code to buy time.
-                         * (as much as 10% of total job time!)
-                         */
-#ifndef NOSQRT
-                        if(model->VDMOSbulkJctBotGradingCoeff == .5 &&
-                                model->VDMOSbulkJctSideGradingCoeff == .5) {
-                            sarg = sargsw = 1/sqrt(arg);
-                        } else {
-                            if(model->VDMOSbulkJctBotGradingCoeff == .5) {
-                                sarg = 1/sqrt(arg);
-                            } else {
-#endif /*NOSQRT*/
-                                sarg = exp(-model->VDMOSbulkJctBotGradingCoeff*
-                                        log(arg));
-#ifndef NOSQRT
-                            }
-                            if(model->VDMOSbulkJctSideGradingCoeff == .5) {
-                                sargsw = 1/sqrt(arg);
-                            } else {
-#endif /*NOSQRT*/
-                                sargsw =exp(-model->VDMOSbulkJctSideGradingCoeff*
-                                        log(arg));
-#ifndef NOSQRT
-                            }
-                        }
-#endif /*NOSQRT*/
-		    /*
-		    lcapbd=here->VDMOSCbd*sarg+
-                                here->VDMOSCbdsw*sargsw;
-				*/
-		    lcapbd2 = model->VDMOStype*0.5/here->VDMOStBulkPot*(
-			here->VDMOSCbd*model->VDMOSbulkJctBotGradingCoeff*
-			sarg/arg + here->VDMOSCbdsw*
-			model->VDMOSbulkJctSideGradingCoeff*sargsw/arg);
-		    lcapbd3 = here->VDMOSCbd*sarg*
-			model->VDMOSbulkJctBotGradingCoeff*
-			(model->VDMOSbulkJctBotGradingCoeff+1);
-		    lcapbd3 += here->VDMOSCbdsw*sargsw*
-			model->VDMOSbulkJctSideGradingCoeff*
-			(model->VDMOSbulkJctSideGradingCoeff+1);
-		    lcapbd3 = lcapbd3/(6*here->VDMOStBulkPot*
-			here->VDMOStBulkPot*arg*arg);
-                    } else {
-			/*
-                        lcapbd=here->VDMOSf2d + vbd * here->VDMOSf3d;
-			*/
-			lcapbd2=0.5*here->VDMOSf3d;
-			lcapbd3=0;
-                    }
             /*
              *     meyer's capacitor model
              */

src/spicelib/devices/vdmos/vdmosload.c

@@ -493,8 +493,6 @@ VDMOSload(GENmodel *inModel, CKTcircuit *ckt)
                              * exp(log()) we use this special case code to buy time.
                              * (as much as 10% of total job time!)
                              */
-                            if (model->VDMOSbulkJctBotGradingCoeff ==
-                                model->VDMOSbulkJctSideGradingCoeff) {
                                 if (model->VDMOSbulkJctBotGradingCoeff == .5) {
                                     sarg = sargsw = 1 / sqrt(arg);
                                 }
@@ -503,29 +501,9 @@ VDMOSload(GENmodel *inModel, CKTcircuit *ckt)
                                         exp(-model->VDMOSbulkJctBotGradingCoeff*
                                             log(arg));
                                 }
-                            }
-                            else {
-                                if (model->VDMOSbulkJctBotGradingCoeff == .5) {
-                                    sarg = 1 / sqrt(arg);
-                                }
-                                else {
-                                    sarg = exp(-model->VDMOSbulkJctBotGradingCoeff*
-                                        log(arg));
-                                }
-                                if (model->VDMOSbulkJctSideGradingCoeff == .5) {
-                                    sargsw = 1 / sqrt(arg);
-                                }
-                                else {
-                                    sargsw = exp(-model->VDMOSbulkJctSideGradingCoeff*
-                                        log(arg));
-                                }
-                            }
                             *(ckt->CKTstate0 + here->VDMOSqbs) =
                                 here->VDMOStBulkPot*(here->VDMOSCbs*
-                                (1 - arg*sarg) / (1 - model->VDMOSbulkJctBotGradingCoeff)
-                                    + here->VDMOSCbssw*
-                                    (1 - arg*sargsw) /
-                                    (1 - model->VDMOSbulkJctSideGradingCoeff));
+                                (1 - arg*sarg) / (1 - model->VDMOSbulkJctBotGradingCoeff));
                             here->VDMOScapbs = here->VDMOSCbs*sarg +
                                 here->VDMOSCbssw*sargsw;
                         }
@@ -551,8 +529,7 @@ VDMOSload(GENmodel *inModel, CKTcircuit *ckt)
                              * exp(log()) we use this special case code to buy time.
                              * (as much as 10% of total job time!)
                              */
-                            if (model->VDMOSbulkJctBotGradingCoeff == .5 &&
-                                model->VDMOSbulkJctSideGradingCoeff == .5) {
+                            if (model->VDMOSbulkJctBotGradingCoeff == .5) {
                                 sarg = sargsw = 1 / sqrt(arg);
                             }
                             else {
@@ -563,21 +540,11 @@ VDMOSload(GENmodel *inModel, CKTcircuit *ckt)
                                     sarg = exp(-model->VDMOSbulkJctBotGradingCoeff*
                                         log(arg));
                                 }
-                                if (model->VDMOSbulkJctSideGradingCoeff == .5) {
-                                    sargsw = 1 / sqrt(arg);
-                                }
-                                else {
-                                    sargsw = exp(-model->VDMOSbulkJctSideGradingCoeff*
-                                        log(arg));
-                                }
                             }
                             *(ckt->CKTstate0 + here->VDMOSqbd) =
                                 here->VDMOStBulkPot*(here->VDMOSCbd*
                                 (1 - arg*sarg)
-                                    / (1 - model->VDMOSbulkJctBotGradingCoeff)
-                                    + here->VDMOSCbdsw*
-                                    (1 - arg*sargsw)
-                                    / (1 - model->VDMOSbulkJctSideGradingCoeff));
+                                    / (1 - model->VDMOSbulkJctBotGradingCoeff));
                             here->VDMOScapbd = here->VDMOSCbd*sarg +
                                 here->VDMOSCbdsw*sargsw;
                         }

src/spicelib/devices/vdmos/vdmosmask.c

@@ -84,12 +84,6 @@ VDMOSmAsk(CKTcircuit *ckt, GENmodel *inst, int which, IFvalue *value)
         case VDMOS_MOD_MJ:
             value->rValue = model->VDMOSbulkJctBotGradingCoeff;
             return(OK);
-        case VDMOS_MOD_CJSW:
-            value->rValue = model->VDMOSsideWallCapFactor;
-            return(OK);
-        case VDMOS_MOD_MJSW:
-            value->rValue = model->VDMOSbulkJctSideGradingCoeff;
-            return(OK);
         case VDMOS_MOD_JS:
             value->rValue = model->VDMOSjctSatCurDensity;
             return(OK);

src/spicelib/devices/vdmos/vdmosmpar.c

@@ -75,14 +75,6 @@ VDMOSmParam(int param, IFvalue *value, GENmodel *inModel)
             model->VDMOSbulkJctBotGradingCoeff = value->rValue;
             model->VDMOSbulkJctBotGradingCoeffGiven = TRUE;
             break;
-        case VDMOS_MOD_CJSW:
-            model->VDMOSsideWallCapFactor = value->rValue;
-            model->VDMOSsideWallCapFactorGiven = TRUE;
-            break;
-        case VDMOS_MOD_MJSW:
-            model->VDMOSbulkJctSideGradingCoeff = value->rValue;
-            model->VDMOSbulkJctSideGradingCoeffGiven = TRUE;
-            break;
         case VDMOS_MOD_JS:
             model->VDMOSjctSatCurDensity = value->rValue;
             model->VDMOSjctSatCurDensityGiven = TRUE;

src/spicelib/devices/vdmos/vdmosset.c

@@ -45,18 +45,12 @@ VDMOSsetup(SMPmatrix *matrix, GENmodel *inModel, CKTcircuit *ckt,
         if (!model->VDMOSbulkCapFactorGiven) {
             model->VDMOSbulkCapFactor = 0;
         }
-        if (!model->VDMOSsideWallCapFactorGiven) {
-            model->VDMOSsideWallCapFactor = 0;
-        }
         if (!model->VDMOSbulkJctPotentialGiven) {
             model->VDMOSbulkJctPotential = .8;
         }
         if (!model->VDMOSbulkJctBotGradingCoeffGiven) {
             model->VDMOSbulkJctBotGradingCoeff = .5;
         }
-        if (!model->VDMOSbulkJctSideGradingCoeffGiven) {
-            model->VDMOSbulkJctSideGradingCoeff = .5;
-        }
         if (!model->VDMOSfwdCapDepCoeffGiven) {
             model->VDMOSfwdCapDepCoeff = .5;
         }

src/spicelib/devices/vdmos/vdmostemp.c

@@ -174,9 +174,6 @@ VDMOStemp(GENmodel *inModel, CKTcircuit *ckt)
             here->VDMOStCbd = model->VDMOScapBD * capfact;
             here->VDMOStCbs = model->VDMOScapBS * capfact;
             here->VDMOStCj = model->VDMOSbulkCapFactor * capfact;
-            capfact = 1/(1+model->VDMOSbulkJctSideGradingCoeff*
-                    (4e-4*(model->VDMOStnom-REFTEMP)-gmaold));
-            here->VDMOStCjsw = model->VDMOSsideWallCapFactor * capfact;
             here->VDMOStBulkPot = fact2 * pbo+pbfact;
             gmanew = (here->VDMOStBulkPot-pbo)/pbo;
             capfact = (1+model->VDMOSbulkJctBotGradingCoeff*
@@ -184,9 +181,6 @@ VDMOStemp(GENmodel *inModel, CKTcircuit *ckt)
             here->VDMOStCbd *= capfact;
             here->VDMOStCbs *= capfact;
             here->VDMOStCj *= capfact;
-            capfact = (1+model->VDMOSbulkJctSideGradingCoeff*
-                    (4e-4*(here->VDMOStemp-REFTEMP)-gmanew));
-            here->VDMOStCjsw *= capfact;
             here->VDMOStDepCap = model->VDMOSfwdCapDepCoeff * here->VDMOStBulkPot;
             if (here->VDMOStSatCurDens == 0) {
                 here->VDMOSsourceVcrit = here->VDMOSdrainVcrit =
@@ -201,22 +195,14 @@ VDMOStemp(GENmodel *inModel, CKTcircuit *ckt)
                 czbdsw=0;
             arg = 1-model->VDMOSfwdCapDepCoeff;
             sarg = exp( (-model->VDMOSbulkJctBotGradingCoeff) * log(arg) );
-            sargsw = exp( (-model->VDMOSbulkJctSideGradingCoeff) * log(arg) );
             here->VDMOSCbd = czbd;
             here->VDMOSCbdsw = czbdsw;
-            here->VDMOSf2d = czbd*(1-model->VDMOSfwdCapDepCoeff*
-                        (1+model->VDMOSbulkJctBotGradingCoeff))* sarg/arg
-                    +  czbdsw*(1-model->VDMOSfwdCapDepCoeff*
-                        (1+model->VDMOSbulkJctSideGradingCoeff))*
-                        sargsw/arg;
-            here->VDMOSf3d = czbd * model->VDMOSbulkJctBotGradingCoeff * sarg/arg/
-                        here->VDMOStBulkPot
-                    + czbdsw * model->VDMOSbulkJctSideGradingCoeff * sargsw/arg /
-                        here->VDMOStBulkPot;
-            here->VDMOSf4d = czbd*here->VDMOStBulkPot*(1-arg*sarg)/
-                        (1-model->VDMOSbulkJctBotGradingCoeff)
-                    + czbdsw*here->VDMOStBulkPot*(1-arg*sargsw)/
-                        (1-model->VDMOSbulkJctSideGradingCoeff)
+            here->VDMOSf2d = czbd * (1 - model->VDMOSfwdCapDepCoeff *
+                (1 + model->VDMOSbulkJctBotGradingCoeff)) * sarg / arg;
+            here->VDMOSf3d = czbd * model->VDMOSbulkJctBotGradingCoeff * sarg / arg /
+                here->VDMOStBulkPot;
+            here->VDMOSf4d = czbd * here->VDMOStBulkPot * (1 - arg * sarg) /
+                (1 - model->VDMOSbulkJctBotGradingCoeff);
                     -here->VDMOSf3d/2*
                         (here->VDMOStDepCap*here->VDMOStDepCap)
                     -here->VDMOStDepCap * here->VDMOSf2d;
@@ -228,22 +214,14 @@ VDMOStemp(GENmodel *inModel, CKTcircuit *ckt)
                 czbssw=0;
             arg = 1-model->VDMOSfwdCapDepCoeff;
             sarg = exp( (-model->VDMOSbulkJctBotGradingCoeff) * log(arg) );
-            sargsw = exp( (-model->VDMOSbulkJctSideGradingCoeff) * log(arg) );
             here->VDMOSCbs = czbs;
             here->VDMOSCbssw = czbssw;
-            here->VDMOSf2s = czbs*(1-model->VDMOSfwdCapDepCoeff*
-                        (1+model->VDMOSbulkJctBotGradingCoeff))* sarg/arg
-                    +  czbssw*(1-model->VDMOSfwdCapDepCoeff*
-                        (1+model->VDMOSbulkJctSideGradingCoeff))*
-                        sargsw/arg;
-            here->VDMOSf3s = czbs * model->VDMOSbulkJctBotGradingCoeff * sarg/arg/
-                        here->VDMOStBulkPot
-                    + czbssw * model->VDMOSbulkJctSideGradingCoeff * sargsw/arg /
-                        here->VDMOStBulkPot;
+            here->VDMOSf2s = czbs * (1 - model->VDMOSfwdCapDepCoeff *
+                (1 + model->VDMOSbulkJctBotGradingCoeff)) * sarg / arg;
+            here->VDMOSf3s = czbs * model->VDMOSbulkJctBotGradingCoeff * sarg / arg /
+                here->VDMOStBulkPot;
             here->VDMOSf4s = czbs*here->VDMOStBulkPot*(1-arg*sarg)/
                         (1-model->VDMOSbulkJctBotGradingCoeff)
-                    + czbssw*here->VDMOStBulkPot*(1-arg*sargsw)/
-                        (1-model->VDMOSbulkJctSideGradingCoeff)
                     -here->VDMOSf3s/2*
                         (here->VDMOStDepCap*here->VDMOStDepCap)
                     -here->VDMOStDepCap * here->VDMOSf2s;