alternative temperature model for extrinsic resistances and subthreshold range

src/spicelib/devices/vdmos/vdmos.c

@@ -89,10 +89,20 @@ IFparm VDMOSmPTable[] = { /* model parameters */
  IOPR("bex",   VDMOS_MOD_MU,    IF_REAL,  "Exponent of gain temperature dependency"),
  IOP( "texp0", VDMOS_MOD_TEXP0, IF_REAL,  "Drain resistance rd0 temperature exponent"),
  IOP( "texp1", VDMOS_MOD_TEXP1, IF_REAL,  "Drain resistance rd1 temperature exponent"),
+ IOP( "trd1",  VDMOS_MOD_TRD1,  IF_REAL,  "Drain resistance linear temperature coefficient"),
+ IOP( "trd2",  VDMOS_MOD_TRD2,  IF_REAL,  "Drain resistance quadratic temperature coefficient"),
+ IOP( "trg1",  VDMOS_MOD_TRG1,  IF_REAL,  "Gate resistance linear temperature coefficient"),
+ IOP( "trg2",  VDMOS_MOD_TRG2,  IF_REAL,  "Gate resistance quadratic temperature coefficient"),
+ IOP( "trs1",  VDMOS_MOD_TRS1,  IF_REAL,  "Source resistance linear temperature coefficient"),
+ IOP( "trs2",  VDMOS_MOD_TRS2,  IF_REAL,  "Source resistance quadratic temperature coefficient"),
+ IOP( "trb1",  VDMOS_MOD_TRB1,  IF_REAL,  "Body resistance linear temperature coefficient"),
+ IOP( "trb2",  VDMOS_MOD_TRB2,  IF_REAL,  "Body resistance quadratic temperature coefficient"),
 
  /* weak inversion */
  IOP("subshift",  VDMOS_MOD_SUBSHIFT,   IF_REAL, "Shift of weak inversion plot on the vgs axis"),
  IOP("ksubthres", VDMOS_MOD_KSUBTHRES,  IF_REAL, "Slope of weak inversion log current versus vgs"),
+ IOP("tksubthres1", VDMOS_MOD_TKSUBTHRES1, IF_REAL,  "Linear temperature coefficient of ksubthres"),
+ IOP("tksubthres2", VDMOS_MOD_TKSUBTHRES2, IF_REAL,  "Quadratic temperature coefficient of ksubthres"),
 
 /* body diode */
  IOP("bv",    VDMOS_MOD_BV,    IF_REAL,   "Vds breakdown voltage"),

src/spicelib/devices/vdmos/vdmosdefs.h

@@ -69,6 +69,7 @@ typedef struct sVDMOSinstance {
     double VDMOStTransconductance;   /* temperature corrected transconductance*/
     double VDMOStPhi;                /* temperature corrected Phi */
     double VDMOStVth;                /* temperature corrected Vth */
+    double VDMOStksubthres;          /* temperature weak inversion slope */
 
     double VDMOSicVDS;   /* initial condition D-S voltage */
     double VDMOSicVGS;   /* initial condition G-S voltage */
@@ -332,13 +333,23 @@ typedef struct sVDMOSmodel {       /* model structure for a resistor */
     double VDIOgradCoeffTemp1;
     double VDIOgradCoeffTemp2;
 
+    double VDMOStcvth;
     double VDMOSrthjc;
     double VDMOSrthca;
     double VDMOScthj;
     double VDMOSmu;
     double VDMOStexp0;
     double VDMOStexp1;
-    double VDMOStcvth;
+    double VDMOStrd1;
+    double VDMOStrd2;
+    double VDMOStrg1;
+    double VDMOStrg2;
+    double VDMOStrs1;
+    double VDMOStrs2;
+    double VDMOStrb1;
+    double VDMOStrb2;
+    double VDMOStksubthres1;
+    double VDMOStksubthres2;
 
     double VDMOSvgsMax;
     double VDMOSvgdMax;
@@ -385,13 +396,23 @@ typedef struct sVDMOSmodel {       /* model structure for a resistor */
     unsigned VDMOSegGiven   :1;
     unsigned VDMOSxtiGiven   :1;
 
+    unsigned VDMOStcvthGiven :1;
     unsigned VDMOSrthjcGiven :1;
     unsigned VDMOSrthcaGiven :1;
     unsigned VDMOScthjGiven :1;
     unsigned VDMOSmuGiven :1;
     unsigned VDMOStexp0Given :1;
     unsigned VDMOStexp1Given :1;
-    unsigned VDMOStcvthGiven :1;
+    unsigned VDMOStrd1Given :1;
+    unsigned VDMOStrd2Given :1;
+    unsigned VDMOStrg1Given :1;
+    unsigned VDMOStrg2Given :1;
+    unsigned VDMOStrs1Given :1;
+    unsigned VDMOStrs2Given :1;
+    unsigned VDMOStrb1Given :1;
+    unsigned VDMOStrb2Given :1;
+    unsigned VDMOStksubthres1Given :1;
+    unsigned VDMOStksubthres2Given :1;
 
     unsigned VDMOSvgsMaxGiven  :1;
     unsigned VDMOSvgdMaxGiven  :1;
@@ -462,13 +483,23 @@ enum {
     VDMOS_MOD_TT,
     VDMOS_MOD_EG,
     VDMOS_MOD_XTI,
+    VDMOS_MOD_TCVTH,
     VDMOS_MOD_RTHJC,
     VDMOS_MOD_RTHCA,
     VDMOS_MOD_CTHJ,
     VDMOS_MOD_MU,
     VDMOS_MOD_TEXP0,
     VDMOS_MOD_TEXP1,
-    VDMOS_MOD_TCVTH,
+    VDMOS_MOD_TRD1,
+    VDMOS_MOD_TRD2,
+    VDMOS_MOD_TRG1,
+    VDMOS_MOD_TRG2,
+    VDMOS_MOD_TRS1,
+    VDMOS_MOD_TRS2,
+    VDMOS_MOD_TRB1,
+    VDMOS_MOD_TRB2,
+    VDMOS_MOD_TKSUBTHRES1,
+    VDMOS_MOD_TKSUBTHRES2,
     VDMOS_MOD_VGS_MAX,
     VDMOS_MOD_VGD_MAX,
     VDMOS_MOD_VDS_MAX,

src/spicelib/devices/vdmos/vdmosload.c

@@ -372,7 +372,7 @@ VDMOSload(GENmodel *inModel, CKTcircuit *ckt)
                  * Scale the voltage overdrive vgst logarithmically in weak inversion.
                  * Best fits LTSPICE curves with shift=0
                  */
-                double slope = model->VDMOSksubthres;
+                double slope = here->VDMOStksubthres;
                 double lambda = model->VDMOSlambda;
                 double theta = model->VDMOStheta;
                 double shift = model->VDMOSsubshift;

src/spicelib/devices/vdmos/vdmosmask.c

@@ -125,6 +125,9 @@ VDMOSmAsk(CKTcircuit *ckt, GENmodel *inst, int which, IFvalue *value)
         case VDMOS_MOD_XTI:
             value->rValue = model->VDMOSxti;
             return(OK);
+        case VDMOS_MOD_TCVTH:
+            value->rValue = model->VDMOStcvth;
+            return(OK);
         case VDMOS_MOD_RTHJC:
             value->rValue = model->VDMOSrthjc; 
             return(OK);
@@ -143,8 +146,35 @@ VDMOSmAsk(CKTcircuit *ckt, GENmodel *inst, int which, IFvalue *value)
         case VDMOS_MOD_TEXP1:
             value->rValue = model->VDMOStexp1; 
             return(OK);
-        case VDMOS_MOD_TCVTH:
-            value->rValue = model->VDMOStcvth;
+        case VDMOS_MOD_TRD1:
+            value->rValue = model->VDMOStrd1; 
+            return(OK);
+        case VDMOS_MOD_TRD2:
+            value->rValue = model->VDMOStrd2; 
+            return(OK);
+        case VDMOS_MOD_TRG1:
+            value->rValue = model->VDMOStrg1; 
+            return(OK);
+        case VDMOS_MOD_TRG2:
+            value->rValue = model->VDMOStrg2; 
+            return(OK);
+        case VDMOS_MOD_TRS1:
+            value->rValue = model->VDMOStrs1; 
+            return(OK);
+        case VDMOS_MOD_TRS2:
+            value->rValue = model->VDMOStrs2; 
+            return(OK);
+        case VDMOS_MOD_TRB1:
+            value->rValue = model->VDMOStrb1; 
+            return(OK);
+        case VDMOS_MOD_TRB2:
+            value->rValue = model->VDMOStrb2; 
+            return(OK);
+        case VDMOS_MOD_TKSUBTHRES1:
+            value->rValue = model->VDMOStksubthres1; 
+            return(OK);
+        case VDMOS_MOD_TKSUBTHRES2:
+            value->rValue = model->VDMOStksubthres2; 
             return(OK);
         case VDMOS_MOD_VGS_MAX:
             value->rValue = model->VDMOSvgsMax;

src/spicelib/devices/vdmos/vdmosmpar.c

@@ -174,6 +174,10 @@ VDMOSmParam(int param, IFvalue *value, GENmodel *inModel)
             model->VDMOSxti = value->rValue;
             model->VDMOSxtiGiven = TRUE;
             break;
+        case VDMOS_MOD_TCVTH:
+            model->VDMOStcvth = value->rValue;
+            model->VDMOStcvthGiven = TRUE;
+            break;
         case  VDMOS_MOD_RTHJC:
             model->VDMOSrthjc = value->rValue;
             model->VDMOSrthjcGiven = TRUE;
@@ -198,9 +202,45 @@ VDMOSmParam(int param, IFvalue *value, GENmodel *inModel)
             model->VDMOStexp1 = value->rValue;
             model->VDMOStexp1Given = TRUE;
             break;
-        case VDMOS_MOD_TCVTH:
-            model->VDMOStcvth = value->rValue;
-            model->VDMOStcvthGiven = TRUE;
+        case  VDMOS_MOD_TRD1:
+            model->VDMOStrd1 = value->rValue;
+            model->VDMOStrd1Given = TRUE;
+            break;
+        case  VDMOS_MOD_TRD2:
+            model->VDMOStrd2 = value->rValue;
+            model->VDMOStrd2Given = TRUE;
+            break;
+        case  VDMOS_MOD_TRG1:
+            model->VDMOStrg1 = value->rValue;
+            model->VDMOStrg1Given = TRUE;
+            break;
+        case  VDMOS_MOD_TRG2:
+            model->VDMOStrg2 = value->rValue;
+            model->VDMOStrg2Given = TRUE;
+            break;
+        case  VDMOS_MOD_TRS1:
+            model->VDMOStrs1 = value->rValue;
+            model->VDMOStrs1Given = TRUE;
+            break;
+        case  VDMOS_MOD_TRS2:
+            model->VDMOStrs2 = value->rValue;
+            model->VDMOStrs2Given = TRUE;
+            break;
+        case  VDMOS_MOD_TRB1:
+            model->VDMOStrb1 = value->rValue;
+            model->VDMOStrb1Given = TRUE;
+            break;
+        case  VDMOS_MOD_TRB2:
+            model->VDMOStrb2 = value->rValue;
+            model->VDMOStrb2Given = TRUE;
+            break;
+        case  VDMOS_MOD_TKSUBTHRES1:
+            model->VDMOStksubthres1 = value->rValue;
+            model->VDMOStksubthres1Given = TRUE;
+            break;
+        case  VDMOS_MOD_TKSUBTHRES2:
+            model->VDMOStksubthres2 = value->rValue;
+            model->VDMOStksubthres2Given = TRUE;
             break;
         case VDMOS_MOD_VGS_MAX:
             model->VDMOSvgsMax = value->rValue;

src/spicelib/devices/vdmos/vdmosset.c

@@ -139,6 +139,36 @@ VDMOSsetup(SMPmatrix *matrix, GENmodel *inModel, CKTcircuit *ckt,
         if (!model->VDMOStexp1Given)
             model->VDMOStexp1 = 0.3;
 
+        if (!model->VDMOStrd1Given)
+            model->VDMOStrd1 = 0.0;
+
+        if (!model->VDMOStrd2Given)
+            model->VDMOStrd2 = 0.0;
+
+        if (!model->VDMOStrg1Given)
+            model->VDMOStrg1 = 0.0;
+
+        if (!model->VDMOStrg2Given)
+            model->VDMOStrg2 = 0.0;
+
+        if (!model->VDMOStrs1Given)
+            model->VDMOStrs1 = 0.0;
+
+        if (!model->VDMOStrs2Given)
+            model->VDMOStrs2 = 0.0;
+
+        if (!model->VDMOStrb1Given)
+            model->VDMOStrb1 = 0.0;
+
+        if (!model->VDMOStrb2Given)
+            model->VDMOStrb2 = 0.0;
+
+        if (!model->VDMOStksubthres1Given)
+            model->VDMOStksubthres1 = 0.0;
+
+        if (!model->VDMOStksubthres2Given)
+            model->VDMOStksubthres2 = 0.0;
+
         if (!model->VDMOSvgsMaxGiven)
             model->VDMOSvgsMax = 1e99;
 

src/spicelib/devices/vdmos/vdmostemp.c

@@ -98,7 +98,16 @@ VDMOStemp(GENmodel *inModel, CKTcircuit *ckt)
 
             here->VDMOStVth = model->VDMOSvth0 - model->VDMOStype * model->VDMOStcvth * dt;
 
-            here->VDMOSdrainResistance =  model->VDMOSdrainResistance / here->VDMOSm * pow(ratio, model->VDMOStexp0);
+            here->VDMOStksubthres =  model->VDMOSksubthres * (1.0 + (model->VDMOStksubthres1 * dt) + (model->VDMOStksubthres2 * dt * dt));
+
+            if (model->VDMOStexp0Given)
+                here->VDMOSdrainResistance =  model->VDMOSdrainResistance / here->VDMOSm * pow(ratio, model->VDMOStexp0);
+            else
+                here->VDMOSdrainResistance =  model->VDMOSdrainResistance / here->VDMOSm * (1.0 + (model->VDMOStrd1 * dt) + (model->VDMOStrd2 * dt * dt));
+
+            here->VDMOSgateConductance =  here->VDMOSgateConductance / (1.0 + (model->VDMOStrg1 * dt) + (model->VDMOStrg2 * dt * dt));
+
+            here->VDMOSsourceConductance =  here->VDMOSsourceConductance / (1.0 + (model->VDMOStrs1 * dt) + (model->VDMOStrs2 * dt * dt));
 
             if (model->VDMOSqsGiven)
                 here->VDMOSqsResistance = model->VDMOSqsResistance / here->VDMOSm * pow(ratio, model->VDMOStexp1);
@@ -206,8 +215,8 @@ VDMOStemp(GENmodel *inModel, CKTcircuit *ckt)
                 + (model->VDIOtranTimeTemp2 * dt * dt);
             here->VDIOtTransitTime = model->VDIOtransitTime * factor;
 
-            /* Series resistance temperature adjust (not implemented yet) */
-            here->VDIOtConductance = here->VDIOconductance;
+            /* Series resistance temperature adjust */
+            here->VDIOtConductance = here->VDIOconductance / (1.0 + (model->VDMOStrb1 * dt) + (model->VDMOStrb2 * dt * dt));
 
             here->VDIOtF2 = exp((1 + here->VDIOtGradingCoeff)*xfc);
             here->VDIOtF3 = 1 - model->VDIOdepletionCapCoeff*