b1eval.c

spice中支持多层次元件模型仿真的可单独运行的插件源码

    Vcut  =  - 40. * N0 * CONSTvt0 ;

/* The following 'if' statement has been modified so that subthreshold  *
 * current computation is always executed unless N0 >= 200. This should *
 * get rid of the Ids kink seen on Ids-Vgs plots at low Vds.            *
 *                                                Peter M. Lee          *
 *                                                6/8/90                *
 *  Old 'if' statement:                                                 *
 *  if( (N0 >=  200) || (Vgs_Vth < Vcut ) || (Vgs_Vth > (-0.5*Vcut)))   */
  
    if (N0 >=  200) {
        goto ChargeComputation;
    }
    
    NB  =  here->B1subthSlopeB;
    ND  =  here->B1subthSlopeD;
    N  =  N0 + NB * vbs + ND * vds; /* subthreshold slope */
    if( N < 0.5 ) N  =  0.5;
    Warg1  =  exp( - vds / CONSTvt0 );
    Wds  =  1 - Warg1;
    Wgs  =  exp( Vgs_Vth / ( N * CONSTvt0 ));
    Vtsquare = CONSTvt0 * CONSTvt0 ;
    Warg2  =  6.04965 * Vtsquare * here->B1betaZero;
    Ilimit  =  4.5 * Vtsquare * here->B1betaZero;
    Iexp = Warg2 * Wgs * Wds;
    DrainCurrent  =  DrainCurrent + Ilimit * Iexp / ( Ilimit + Iexp );
    Temp1  =  Ilimit / ( Ilimit + Iexp );
    Temp1  =  Temp1 * Temp1;
    Temp3  = Ilimit / ( Ilimit + Wgs * Warg2 );
    Temp3=Temp3 * Temp3 * Warg2 * Wgs;
/*    if ( Temp3 > Ilimit ) Temp3=Ilimit;*/
    gm  =  gm + Temp1 * Iexp / ( N * CONSTvt0 );
    /* gds term has been modified to prevent blow up at Vds=0 */
    gds = gds + Temp3 * ( -Wds / N / CONSTvt0 * (dVthdVds + 
        Vgs_Vth * ND / N ) + Warg1 / CONSTvt0 );
    gmbs  =  gmbs - Temp1 * Iexp * (dVthdVbs + Vgs_Vth * NB / N ) /  
        ( N * CONSTvt0 );

ChargeComputation:

    /* Some Limiting of DC Parameters */
    if(DrainCurrent < 0.0) DrainCurrent = 0.0;
    if(gm < 0.0) gm = 0.0;
    if(gds < 0.0) gds = 0.0;
    if(gmbs < 0.0) gmbs = 0.0;

    WLCox = model->B1Cox * 
        (here->B1l - model->B1deltaL * 1.e-6) * 
        (here->B1w - model->B1deltaW * 1.e-6) * 1.e4;   /* F */

    if( ! ChargeComputationNeeded )  {  
        qg  = 0;
        qd = 0;
        qb = 0;
        cggb = 0;
        cgsb = 0;
        cgdb = 0;
        cdgb = 0;
        cdsb = 0;
        cddb = 0;
        cbgb = 0;
        cbsb = 0;
        cbdb = 0;
        goto finished;
    }
    G  =  1. - 1./(1.744+0.8364 * Vpb);
    A  =  1. + 0.5*G*K1/SqrtVpb;
    A = MAX( A, 1.0);   /* Modified */
    /*Arg  =  1 + Ugs * Vgs_Vth;*/
    dGdVbs  =  -0.8364 * (1-G) * (1-G);
    dAdVbs  =  0.25 * K1 / SqrtVpb *(2*dGdVbs + G/Vpb);
    Phi  =  MAX( 0.1, Phi);

    if( model->B1channelChargePartitionFlag >= 1 ) {

/*0/100 partitioning for drain/source chArges at the saturation region*/
        Vth0 = Vfb + Phi + K1 * SqrtVpb;
        Vgs_Vth = vgs - Vth0;
        Arg1 = A * vds;
        Arg2 = Vgs_Vth - 0.5 * Arg1;
        Arg3 = vds - Arg1;
        Arg5 = Arg1 * Arg1;
        dVthdVbs =  - 0.5 * K1 / SqrtVpb;
        dAdVbs = 0.5 * K1 * (0.5 * G / Vpb - 0.8364 * (1 -G) * (1 - G) ) / 
            SqrtVpb ;
        Ent = MAX(Arg2,1.0e-8);
        dEntdVds =  - 0.5 * A;
        dEntdVbs =  - dVthdVbs - 0.5 * vds * dAdVbs;
        Vcom = Vgs_Vth * Vgs_Vth / 6.0 - 1.25e-1 * Arg1 * 
            Vgs_Vth + 2.5e-2 * Arg5;
        VdsPinchoff = MAX( Vgs_Vth / A, 0.0);
        Vgb  =  vgs  -  vbs ;
        Vgb_Vfb  =  Vgb  -  Vfb;

        if( Vgb_Vfb < 0){
            /* Accumulation Region */
            qg  =  WLCox * Vgb_Vfb;
            qb  =  - qg;
            qd  =  0. ;
            cggb  =  WLCox;
            cgdb  =  0.;
            cgsb  =  0.;
            cbgb  =  -WLCox;
            cbdb  =  0.;
            cbsb  =  0.;
            cdgb  =  0.;
            cddb  =  0.;
            cdsb  =  0.;
            goto finished;
        } else if ( vgs < Vth0 ){
            /* Subthreshold Region */
            qg  =  0.5 * WLCox * K1 * K1 * (-1 + 
                sqrt(1 + 4 * Vgb_Vfb / (K1 * K1)));
            qb  =  -qg;
            qd  =  0.;
            cggb  =  WLCox / sqrt(1 + 4 * Vgb_Vfb / (K1 * K1));
            cgdb  =  cgsb = 0.;
            cbgb  =  -cggb;
            cbdb  =  cbsb = cdgb = cddb = cdsb = 0.0;
            goto finished;
        } else if( vds < VdsPinchoff ){    /* triode region  */
            /*Vgs_Vth2 = Vgs_Vth*Vgs_Vth;*/
            EntSquare = Ent * Ent;
            Argl1 = 1.2e1 * EntSquare;
            Argl2 = 1.0 - A;
            Argl3 = Arg1 * vds;
            /*Argl4 = Vcom/Ent/EntSquare;*/
            if (Ent > 1.0e-8) {   
                Argl5 = Arg1 / Ent;
                /*Argl6 = Vcom/EntSquare;*/  
            } else {   
                Argl5 = 2.0;
                Argl6 = 4.0 / 1.5e1;
            }
            Argl7 = Argl5 / 1.2e1;
            Argl8 = 6.0 * Ent;
            Argl9 = 0.125 * Argl5 * Argl5;
            qg = WLCox * (vgs - Vfb - Phi - 0.5 * vds + vds * Argl7);
            qb = WLCox * ( - Vth0 + Vfb + Phi + 0.5 * Arg3 - Arg3 * Argl7);
            qd =  - WLCox * (0.5 * Vgs_Vth - 0.75 * Arg1 + 
                0.125 * Arg1 * Argl5);
            cggb = WLCox * (1.0 - Argl3 / Argl1);
            cgdb = WLCox * ( - 0.5 + Arg1 / Argl8 - Argl3 * dEntdVds / 
                Argl1);
            cgbb = WLCox * (vds * vds * dAdVbs * Ent - Argl3 * dEntdVbs) /
                Argl1;
            cgsb =  - (cggb + cgdb + cgbb);
            cbgb = WLCox * Argl3 * Argl2 / Argl1;
            cbdb = WLCox * Argl2 * (0.5 - Arg1 / Argl8 + Argl3 * dEntdVds /
                Argl1);
            cbbb =  - WLCox * (dVthdVbs + 0.5 * vds * dAdVbs + vds * 
                vds * ((1.0 - 2.0 * A) * dAdVbs * Ent - Argl2 * 
                A * dEntdVbs) / Argl1);
            cbsb =  - (cbgb + cbdb + cbbb);
            cdgb =  - WLCox * (0.5 - Argl9);
            cddb = WLCox * (0.75 * A - 0.25 * A * Arg1 / Ent + 
                Argl9 * dEntdVds);
            cdbb = WLCox * (0.5 * dVthdVbs + vds * dAdVbs * 
                (0.75 - 0.25 * Argl5 ) + Argl9 * dEntdVbs);
            cdsb =  - (cdgb + cddb + cdbb);
            goto finished;
        } else if( vds >= VdsPinchoff ) {    /* saturation region   */
            Args1 = 1.0 / (3.0 * A);
            qg = WLCox * (vgs - Vfb - Phi - Vgs_Vth * Args1);
            qb = WLCox * (Vfb + Phi - Vth0 + (1.0 - A) * Vgs_Vth * Args1);
            qd = 0.0;
            cggb = WLCox * (1.0 - Args1);
            cgdb = 0.0;
            cgbb = WLCox * Args1 * (dVthdVbs + Vgs_Vth * dAdVbs / A);
            cgsb =  - (cggb + cgdb + cgbb);
            cbgb = WLCox * (Args1 - 1.0 / 3.0);
            cbdb = 0.0;
            cbbb =  - WLCox * ((2.0 / 3.0 + Args1) * dVthdVbs  +  
                Vgs_Vth * Args1 * dAdVbs / A);      /* Modified */
            cbsb =  - (cbgb + cbdb + cbbb);
            cdgb = 0.0;
            cddb = 0.0;
            cdsb = 0.0;
            goto finished;
        }

        goto finished;

    } else {
        /* ChannelChargePartionFlag  < = 0 */

/*40/60 partitioning for drain/source chArges at the saturation region*/
        co4v15 = 4./15.;
        Vth0 = Vfb+Phi+K1*SqrtVpb;
        Vgs_Vth = vgs-Vth0;
        Arg1 = A*vds;
        Arg2 = Vgs_Vth-0.5*Arg1;
        Arg3 = vds-Arg1;
        Arg5 = Arg1*Arg1;
        dVthdVbs = -0.5*K1/SqrtVpb;
        dAdVbs = 0.5*K1*(0.5*G/Vpb-0.8364*(1-G)*(1-G))/SqrtVpb;
        Ent = MAX(Arg2,1.0e-8);
        dEntdVds = -0.5*A;
        dEntdVbs = -dVthdVbs-0.5*vds*dAdVbs;
        Vcom = Vgs_Vth*Vgs_Vth/6.0-1.25e-1*Arg1*Vgs_Vth+2.5e-2*Arg5;
        VdsPinchoff = MAX( Vgs_Vth/A, 0.0);
        Vgb  =  vgs - vbs ;
        Vgb_Vfb  =  Vgb - Vfb;
  
        if( Vgb_Vfb < 0) {           /* Accumulation Region */
            qg  =  WLCox * Vgb_Vfb;
            qb  =  - qg;
            qd  =  0. ;
            cggb  =  WLCox;
            cgdb  =  0.;
            cgsb  =  0.;
            cbgb  =  -WLCox;
            cbdb  =  0.;
            cbsb  =  0.;
            cdgb  =  0.;
            cddb  =  0.;
            cdsb  =  0.;
            goto finished;
        } else if ( vgs < Vth0 ) {    /* Subthreshold Region */
            qg  =  0.5 * WLCox * K1 * K1 * (-1+sqrt(1+4*Vgb_Vfb/(K1*K1)));
            qb  =  -qg;
            qd  =  0.;
            cggb  =  WLCox/sqrt(1+4*Vgb_Vfb/(K1*K1));
            cgdb  =  cgsb = 0.;
            cbgb  =  -cggb;
            cbdb  =  cbsb = cdgb = cddb = cdsb = 0.0;
            goto finished;
        } else if ( vds < VdsPinchoff ) {      /* triode region */
    
            Vgs_VthSquare = Vgs_Vth*Vgs_Vth;
            EntSquare = Ent*Ent;
            Argl1 = 1.2e1*EntSquare;
            Argl2 = 1.0-A;
            Argl3 = Arg1*vds;
            Argl4 = Vcom/Ent/EntSquare;
            if (Ent > 1.0e-8) { 
                Argl5 = Arg1/Ent;
                Argl6 = Vcom/EntSquare;    
            } else {   
                Argl5 = 2.0;
                Argl6 = 4.0/1.5e1;   
            }
            Argl7 = Argl5/1.2e1;
            Argl8 = 6.0*Ent;
            qg = WLCox*(vgs-Vfb-Phi-0.5*vds+vds*Argl7);
            qb = WLCox*(-Vth0+Vfb+Phi+0.5*Arg3-Arg3*Argl7);
            qd = -WLCox*(0.5*(Vgs_Vth-Arg1)+Arg1*Argl6);
            cggb = WLCox*(1.0-Argl3/Argl1);
            cgdb = WLCox*(-0.5+Arg1/Argl8-Argl3*dEntdVds/Argl1);
            cgbb = WLCox*(vds*vds*dAdVbs*Ent-Argl3*dEntdVbs)/Argl1;
            cgsb = -(cggb+cgdb+cgbb);
            cbgb = WLCox*Argl3*Argl2/Argl1;
            cbdb = WLCox*Argl2*(0.5-Arg1/Argl8+Argl3*dEntdVds/Argl1);
            cbbb = -WLCox*(dVthdVbs+0.5*vds*dAdVbs+vds*vds*((1.0-2.0*A)
                *dAdVbs*Ent-Argl2*A*dEntdVbs)/Argl1);
            cbsb = -(cbgb+cbdb+cbbb);
            cdgb = -WLCox*(0.5+Arg1*(4.0*Vgs_Vth-1.5*Arg1)/Argl1-
                2.0*Arg1*Argl4);
            cddb = WLCox*(0.5*A+2.0*Arg1*dEntdVds*Argl4-A*(2.0*Vgs_VthSquare
                -3.0*Arg1*Vgs_Vth+0.9*Arg5)/Argl1);
            cdbb = WLCox*(0.5*dVthdVbs+0.5*vds*dAdVbs+2.0*Arg1*dEntdVbs
                *Argl4-vds*(2.0*Vgs_VthSquare*dAdVbs-4.0*A*Vgs_Vth*dVthdVbs-3.0
                *Arg1*Vgs_Vth*dAdVbs+1.5*A*Arg1*dVthdVbs+0.9*Arg5*dAdVbs)
                /Argl1);
            cdsb = -(cdgb+cddb+cdbb);
            goto finished;
        } else if( vds >= VdsPinchoff ) {      /* saturation region */
     
            Args1 = 1.0/(3.0*A);
            qg = WLCox*(vgs-Vfb-Phi-Vgs_Vth*Args1);
            qb = WLCox*(Vfb+Phi-Vth0+(1.0-A)*Vgs_Vth*Args1);
            qd = -co4v15*WLCox*Vgs_Vth;
            cggb = WLCox*(1.0-Args1);
            cgdb = 0.0;
            cgbb = WLCox*Args1*(dVthdVbs+Vgs_Vth*dAdVbs/A);
            cgsb = -(cggb+cgdb+cgbb);
            cbgb = WLCox*(Args1-1.0/3.0);
            cbdb = 0.0;
            cbbb = -WLCox*((2.0/3.0+Args1)*dVthdVbs+Vgs_Vth*Args1*dAdVbs/A);
            cbsb = -(cbgb+cbdb+cbbb);
            cdgb = -co4v15*WLCox;
            cddb = 0.0;
            cdbb = co4v15*WLCox*dVthdVbs;
            cdsb = -(cdgb+cddb+cdbb);
            goto finished;
        }
    }

finished:       /* returning Values to Calling Routine */
       
    *gmPointer  =  MAX(gm,0.0);
    *gdsPointer  =  MAX( gds, 0.0); 
    *gmbsPointer  =  MAX(gmbs,0.0);
    *qgPointer  =  qg;
    *qbPointer  =  qb;
    *qdPointer  =  qd;
    *cggbPointer  =  cggb;
    *cgdbPointer  =  cgdb;
    *cgsbPointer  =  cgsb;
    *cbgbPointer  =  cbgb;
    *cbdbPointer  =  cbdb;
    *cbsbPointer  =  cbsb;
    *cdgbPointer  =  cdgb;
    *cddbPointer  =  cddb;
    *cdsbPointer  =  cdsb; 
    *cdrainPointer  =  MAX(DrainCurrent,0.0);
    *vonPointer  =  Von;
    *vdsatPointer  =  VdsSat;

}