Add coil diameter dia to the inductor parameters.

dia (diameter) takes preference over csect (cross section)

src/spicelib/devices/ind/ind.c

@@ -44,6 +44,7 @@ IFparm INDmPTable[] = { /* model parameters */
     IOPA(  "tc2",    IND_MOD_TC2,      IF_REAL,"Second order temp. coefficient"),
     IOPXU( "tnom",   IND_MOD_TNOM,     IF_REAL,"Parameter measurement temperature"),
     IOPA(  "csect",  IND_MOD_CSECT,    IF_REAL,"Inductor cross section"),
+    IOPA(  "dia",    IND_MOD_DIA,      IF_REAL,"Inductor diameter"),
     IOPA(  "length", IND_MOD_LENGTH,   IF_REAL,"Inductor length"),
     IOPA(  "nt",     IND_MOD_NT,       IF_REAL,"Model number of turns"),
     IOPA(  "mu",     IND_MOD_MU,       IF_REAL,"Relative magnetic permeability"),

src/spicelib/devices/ind/inddefs.h

@@ -101,6 +101,7 @@ struct sINDmodel {             /* model structure for an inductor */
     double INDtempCoeff1;  /* first temperature coefficient */
     double INDtempCoeff2;  /* second  temperature coefficient */
     double INDcsect;       /* Cross section of inductor */
+    double INDdia;         /* Diameter of (cylindrical) inductor */
     double INDlength;      /* Mean length of magnetic path */
     double INDmodNt;       /* Model number of turns */
     double INDmu;          /* Relative magnetic permeability */
@@ -109,6 +110,7 @@ struct sINDmodel {             /* model structure for an inductor */
     unsigned INDtc1Given   : 1; /* flag to indicate tc1 was specified */
     unsigned INDtc2Given   : 1; /* flag to indicate tc2 was specified */
     unsigned INDcsectGiven : 1; /* flag to indicate cross section given */
+    unsigned INDdiaGiven   : 1; /* flag to indicate diameter given */
     unsigned INDlengthGiven: 1; /* flag to indicate length given */
     unsigned INDmodNtGiven : 1; /* flag to indicate mod. n. of turns given */
     unsigned INDmuGiven    : 1; /* flag to indicate mu_r given */
@@ -196,6 +198,7 @@ enum {
     IND_MOD_TC2,
     IND_MOD_TNOM,
     IND_MOD_CSECT,
+    IND_MOD_DIA,
     IND_MOD_LENGTH,
     IND_MOD_NT,
     IND_MOD_MU,

src/spicelib/devices/ind/indmpar.c

@@ -37,6 +37,10 @@ INDmParam(int param, IFvalue *value, GENmodel *inModel)
         mod->INDcsect = value->rValue;
         mod->INDcsectGiven = TRUE;
         break;
+    case IND_MOD_DIA:
+        mod->INDdia = value->rValue;
+        mod->INDdiaGiven = TRUE;
+        break;
     case IND_MOD_LENGTH :
         mod->INDlength = value->rValue;
         mod->INDlengthGiven = TRUE;

src/spicelib/devices/ind/indsetup.c

@@ -32,10 +32,10 @@ INDsetup(SMPmatrix *matrix, GENmodel *inModel, CKTcircuit *ckt, int *states)
         if (!model->INDmIndGiven) {
              model->INDmInd = 0.0;
         }
-	if (!model->INDtnomGiven) {
+        if (!model->INDtnomGiven) {
              model->INDtnom = ckt->CKTnomTemp;
         }
-	if (!model->INDtc1Given) {
+        if (!model->INDtc1Given) {
              model->INDtempCoeff1 = 0.0;
         }
         if (!model->INDtc2Given) {
@@ -44,6 +44,9 @@ INDsetup(SMPmatrix *matrix, GENmodel *inModel, CKTcircuit *ckt, int *states)
         if (!model->INDcsectGiven){
              model->INDcsect = 0.0;
         }
+        if (!model->INDdiaGiven){
+             model->INDdia = 0.0;
+        }
         if (!model->INDlengthGiven) {
              model->INDlength = 0.0;
         }
@@ -54,30 +57,32 @@ INDsetup(SMPmatrix *matrix, GENmodel *inModel, CKTcircuit *ckt, int *states)
              model->INDmu = 1.0;
         }
 
-	/* precompute specific inductance (one turn) */
+        /* diameter takes preference over cross section */
-	if((model->INDlengthGiven) && (model->INDlength > 0.0)) {
+        if (model->INDdiaGiven) {
-         model->INDspecInd = (model->INDmu * CONSTmuZero
+            model->INDcsect = PI * model->INDdia * model->INDdia / 4.;
-		     * model->INDcsect) / model->INDlength;
+        }
-	} else  {
-	     model->INDspecInd = 0.0;
-	}
           
-    /* Lundin's geometry correction factor */
+        /* precompute specific inductance (one turn) */
-    model->INDspecInd *= Lundin(model->INDlength, model->INDcsect);
+        if((model->INDlengthGiven) && (model->INDlength > 0.0)) {
+             model->INDspecInd = (model->INDmu * CONSTmuZero
+		         * model->INDcsect) / model->INDlength;
+        } else  {
+            model->INDspecInd = 0.0;
+        }
+
+        /* Lundin's geometry correction factor */
+        model->INDspecInd *= Lundin(model->INDlength, model->INDcsect);
 
 /*
-    double kl = Lundin(model->INDlength, model->INDcsect);
+        double kl = Lundin(model->INDlength, model->INDcsect);
-    double Dl = model->INDlength / sqrt(model->INDcsect / PI) / 2.;
+        double Dl = model->INDlength / sqrt(model->INDcsect / PI) / 2.;
-    fprintf(stdout, "Lundin's correction factor %f at l/D %f\n", kl, Dl);
+        fprintf(stdout, "Lundin's correction factor %f at l/D %f\n", kl, Dl);
 */
 
-    /* How many turns ? */
+        /* How many turns ? */
-	if (!model->INDmIndGiven) 
+        if (!model->INDmIndGiven) 
             model->INDmInd = model->INDmodNt * model->INDmodNt * model->INDspecInd;
 	
-            
-        
-	
         /* loop through all the instances of the model */
         for (here = INDinstances(model); here != NULL ;
                 here=INDnextInstance(here)) {