b4ld.c

ngspice又一个电子CAD仿真软件代码.功能更全

	      if (Rds > 0.0)
		  here->BSIM4grdsw = 1.0 / Rds; 
	      else
                  here->BSIM4grdsw = 0.0;
          }
	  
          /* Calculate Abulk */
	  T9 = 0.5 * pParam->BSIM4k1ox * Lpe_Vb / sqrtPhis;
          T1 = T9 + here->BSIM4k2ox - pParam->BSIM4k3b * Vth_NarrowW;
          dT1_dVb = -T9 / sqrtPhis * dsqrtPhis_dVb;

          T9 = sqrt(pParam->BSIM4xj * Xdep);
          tmp1 = Leff + 2.0 * T9;
          T5 = Leff / tmp1; 
          tmp2 = pParam->BSIM4a0 * T5;
          tmp3 = pParam->BSIM4weff + pParam->BSIM4b1; 
          tmp4 = pParam->BSIM4b0 / tmp3;
          T2 = tmp2 + tmp4;
          dT2_dVb = -T9 / tmp1 / Xdep * dXdep_dVb;
          T6 = T5 * T5;
          T7 = T5 * T6;

          Abulk0 = 1.0 + T1 * T2; 
          dAbulk0_dVb = T1 * tmp2 * dT2_dVb + T2 * dT1_dVb;

          T8 = pParam->BSIM4ags * pParam->BSIM4a0 * T7;
          dAbulk_dVg = -T1 * T8;
          Abulk = Abulk0 + dAbulk_dVg * Vgsteff; 
          dAbulk_dVb = dAbulk0_dVb - T8 * Vgsteff * (dT1_dVb
		     + 3.0 * T1 * dT2_dVb);

          if (Abulk0 < 0.1) /* added to avoid the problems caused by Abulk0 */
	  {   T9 = 1.0 / (3.0 - 20.0 * Abulk0);
	      Abulk0 = (0.2 - Abulk0) * T9;
	      dAbulk0_dVb *= T9 * T9;
	  }

          if (Abulk < 0.1)
	  {   T9 = 1.0 / (3.0 - 20.0 * Abulk);
	      Abulk = (0.2 - Abulk) * T9;
              T10 = T9 * T9;
	      dAbulk_dVb *= T10;
              dAbulk_dVg *= T10;
	  }
	  here->BSIM4Abulk = Abulk;

          T2 = pParam->BSIM4keta * Vbseff;
	  if (T2 >= -0.9)
	  {   T0 = 1.0 / (1.0 + T2);
              dT0_dVb = -pParam->BSIM4keta * T0 * T0;
	  }
	  else
	  {   T1 = 1.0 / (0.8 + T2);
	      T0 = (17.0 + 20.0 * T2) * T1;
              dT0_dVb = -pParam->BSIM4keta * T1 * T1;
	  }
	  dAbulk_dVg *= T0;
	  dAbulk_dVb = dAbulk_dVb * T0 + Abulk * dT0_dVb;
	  dAbulk0_dVb = dAbulk0_dVb * T0 + Abulk0 * dT0_dVb;
	  Abulk *= T0;
	  Abulk0 *= T0;

          /* Mobility calculation */
          if (model->BSIM4mobMod == 0)
          {   T0 = Vgsteff + Vth + Vth;
              T2 = pParam->BSIM4ua + pParam->BSIM4uc * Vbseff;
              T3 = T0 / model->BSIM4toxe;
              T5 = T3 * (T2 + pParam->BSIM4ub * T3);
              dDenomi_dVg = (T2 + 2.0 * pParam->BSIM4ub * T3) / model->BSIM4toxe;
              dDenomi_dVd = dDenomi_dVg * 2.0 * dVth_dVd;
              dDenomi_dVb = dDenomi_dVg * 2.0 * dVth_dVb + pParam->BSIM4uc * T3;
          }
          else if (model->BSIM4mobMod == 1)
          {   T0 = Vgsteff + Vth + Vth;
              T2 = 1.0 + pParam->BSIM4uc * Vbseff;
              T3 = T0 / model->BSIM4toxe;
              T4 = T3 * (pParam->BSIM4ua + pParam->BSIM4ub * T3);
              T5 = T4 * T2;
              dDenomi_dVg = (pParam->BSIM4ua + 2.0 * pParam->BSIM4ub * T3) * T2
                          / model->BSIM4toxe;
              dDenomi_dVd = dDenomi_dVg * 2.0 * dVth_dVd;
              dDenomi_dVb = dDenomi_dVg * 2.0 * dVth_dVb + pParam->BSIM4uc * T4;
          }
	  else
	  {   T0 = (Vgsteff + here->BSIM4vtfbphi1) / model->BSIM4toxe;
	      T1 = exp(pParam->BSIM4eu * log(T0));
	      dT1_dVg = T1 * pParam->BSIM4eu / T0 / model->BSIM4toxe;
	      T2 = pParam->BSIM4ua + pParam->BSIM4uc * Vbseff;
	      T5 = T1 * T2;
 	      dDenomi_dVg = T2 * dT1_dVg;
              dDenomi_dVd = 0.0;
              dDenomi_dVb = T1 * pParam->BSIM4uc;
	  }

	  if (T5 >= -0.8)
	  {   Denomi = 1.0 + T5;
	  }
	  else
	  {   T9 = 1.0 / (7.0 + 10.0 * T5);
	      Denomi = (0.6 + T5) * T9;
	      T9 *= T9;
              dDenomi_dVg *= T9;
              dDenomi_dVd *= T9;
              dDenomi_dVb *= T9;
	  }

          here->BSIM4ueff = ueff = here->BSIM4u0temp / Denomi;
	  T9 = -ueff / Denomi;
          dueff_dVg = T9 * dDenomi_dVg;
          dueff_dVd = T9 * dDenomi_dVd;
          dueff_dVb = T9 * dDenomi_dVb;

          /* Saturation Drain Voltage  Vdsat */
          WVCox = Weff * here->BSIM4vsattemp * model->BSIM4coxe;
          WVCoxRds = WVCox * Rds; 

          Esat = 2.0 * here->BSIM4vsattemp / ueff;
          here->BSIM4EsatL = EsatL = Esat * Leff;
          T0 = -EsatL /ueff;
          dEsatL_dVg = T0 * dueff_dVg;
          dEsatL_dVd = T0 * dueff_dVd;
          dEsatL_dVb = T0 * dueff_dVb;
  
	  /* Sqrt() */
          a1 = pParam->BSIM4a1;
	  if (a1 == 0.0)
	  {   Lambda = pParam->BSIM4a2;
	      dLambda_dVg = 0.0;
	  }
	  else if (a1 > 0.0)
	  {   T0 = 1.0 - pParam->BSIM4a2;
	      T1 = T0 - pParam->BSIM4a1 * Vgsteff - 0.0001;
	      T2 = sqrt(T1 * T1 + 0.0004 * T0);
	      Lambda = pParam->BSIM4a2 + T0 - 0.5 * (T1 + T2);
	      dLambda_dVg = 0.5 * pParam->BSIM4a1 * (1.0 + T1 / T2);
	  }
	  else
	  {   T1 = pParam->BSIM4a2 + pParam->BSIM4a1 * Vgsteff - 0.0001;
	      T2 = sqrt(T1 * T1 + 0.0004 * pParam->BSIM4a2);
	      Lambda = 0.5 * (T1 + T2);
	      dLambda_dVg = 0.5 * pParam->BSIM4a1 * (1.0 + T1 / T2);
	  }

          Vgst2Vtm = Vgsteff + 2.0 * Vtm;
          if (Rds > 0)
          {   tmp2 = dRds_dVg / Rds + dWeff_dVg / Weff;
              tmp3 = dRds_dVb / Rds + dWeff_dVb / Weff;
          }
          else
          {   tmp2 = dWeff_dVg / Weff;
              tmp3 = dWeff_dVb / Weff;
	  }
          if ((Rds == 0.0) && (Lambda == 1.0))
          {   T0 = 1.0 / (Abulk * EsatL + Vgst2Vtm);
              tmp1 = 0.0;
	      T1 = T0 * T0;
	      T2 = Vgst2Vtm * T0;
              T3 = EsatL * Vgst2Vtm;
              Vdsat = T3 * T0;
                           
              dT0_dVg = -(Abulk * dEsatL_dVg + EsatL * dAbulk_dVg + 1.0) * T1;
              dT0_dVd = -(Abulk * dEsatL_dVd) * T1; 
              dT0_dVb = -(Abulk * dEsatL_dVb + dAbulk_dVb * EsatL) * T1;   

              dVdsat_dVg = T3 * dT0_dVg + T2 * dEsatL_dVg + EsatL * T0;
              dVdsat_dVd = T3 * dT0_dVd + T2 * dEsatL_dVd;
              dVdsat_dVb = T3 * dT0_dVb + T2 * dEsatL_dVb;   
          }
          else
          {   tmp1 = dLambda_dVg / (Lambda * Lambda);
              T9 = Abulk * WVCoxRds;
	      T8 = Abulk * T9;
	      T7 = Vgst2Vtm * T9;
              T6 = Vgst2Vtm * WVCoxRds;
              T0 = 2.0 * Abulk * (T9 - 1.0 + 1.0 / Lambda); 
              dT0_dVg = 2.0 * (T8 * tmp2 - Abulk * tmp1
		      + (2.0 * T9 + 1.0 / Lambda - 1.0) * dAbulk_dVg);
             
              dT0_dVb = 2.0 * (T8 * (2.0 / Abulk * dAbulk_dVb + tmp3)
		      + (1.0 / Lambda - 1.0) * dAbulk_dVb);
	      dT0_dVd = 0.0; 
              T1 = Vgst2Vtm * (2.0 / Lambda - 1.0) + Abulk * EsatL + 3.0 * T7;
             
              dT1_dVg = (2.0 / Lambda - 1.0) - 2.0 * Vgst2Vtm * tmp1
		      + Abulk * dEsatL_dVg + EsatL * dAbulk_dVg + 3.0 * (T9
		      + T7 * tmp2 + T6 * dAbulk_dVg);
              dT1_dVb = Abulk * dEsatL_dVb + EsatL * dAbulk_dVb
	              + 3.0 * (T6 * dAbulk_dVb + T7 * tmp3);
              dT1_dVd = Abulk * dEsatL_dVd;

              T2 = Vgst2Vtm * (EsatL + 2.0 * T6);
              dT2_dVg = EsatL + Vgst2Vtm * dEsatL_dVg
		      + T6 * (4.0 + 2.0 * Vgst2Vtm * tmp2);
              dT2_dVb = Vgst2Vtm * (dEsatL_dVb + 2.0 * T6 * tmp3);
              dT2_dVd = Vgst2Vtm * dEsatL_dVd;

              T3 = sqrt(T1 * T1 - 2.0 * T0 * T2);
              Vdsat = (T1 - T3) / T0;

              dT3_dVg = (T1 * dT1_dVg - 2.0 * (T0 * dT2_dVg + T2 * dT0_dVg))
	              / T3;
              dT3_dVd = (T1 * dT1_dVd - 2.0 * (T0 * dT2_dVd + T2 * dT0_dVd))
		      / T3;
              dT3_dVb = (T1 * dT1_dVb - 2.0 * (T0 * dT2_dVb + T2 * dT0_dVb))
		      / T3;

              dVdsat_dVg = (dT1_dVg - (T1 * dT1_dVg - dT0_dVg * T2
			 - T0 * dT2_dVg) / T3 - Vdsat * dT0_dVg) / T0;
              dVdsat_dVb = (dT1_dVb - (T1 * dT1_dVb - dT0_dVb * T2
			 - T0 * dT2_dVb) / T3 - Vdsat * dT0_dVb) / T0;
              dVdsat_dVd = (dT1_dVd - (T1 * dT1_dVd - T0 * dT2_dVd) / T3) / T0;
          }
          here->BSIM4vdsat = Vdsat;

          /* Calculate Vdseff */
          T1 = Vdsat - Vds - pParam->BSIM4delta;
          dT1_dVg = dVdsat_dVg;
          dT1_dVd = dVdsat_dVd - 1.0;
          dT1_dVb = dVdsat_dVb;

          T2 = sqrt(T1 * T1 + 4.0 * pParam->BSIM4delta * Vdsat);
	  T0 = T1 / T2;
   	  T9 = 2.0 * pParam->BSIM4delta;
	  T3 = T9 / T2;
          dT2_dVg = T0 * dT1_dVg + T3 * dVdsat_dVg;
          dT2_dVd = T0 * dT1_dVd + T3 * dVdsat_dVd;
          dT2_dVb = T0 * dT1_dVb + T3 * dVdsat_dVb;

	  if (T1 >= 0.0)
	  {   Vdseff = Vdsat - 0.5 * (T1 + T2);
	      dVdseff_dVg = dVdsat_dVg - 0.5 * (dT1_dVg + dT2_dVg);
              dVdseff_dVd = dVdsat_dVd - 0.5 * (dT1_dVd + dT2_dVd);
              dVdseff_dVb = dVdsat_dVb - 0.5 * (dT1_dVb + dT2_dVb);
	  }
	  else
	  {   T4 = T9 / (T2 - T1);
	      T5 = 1.0 - T4;
	      T6 = Vdsat * T4 / (T2 - T1);
	      Vdseff = Vdsat * T5;
              dVdseff_dVg = dVdsat_dVg * T5 + T6 * (dT2_dVg - dT1_dVg);
              dVdseff_dVd = dVdsat_dVd * T5 + T6 * (dT2_dVd - dT1_dVd);
              dVdseff_dVb = dVdsat_dVb * T5 + T6 * (dT2_dVb - dT1_dVb);
	  }

          if (Vds == 0.0)
          {  Vdseff = 0.0;
             dVdseff_dVg = 0.0;
             dVdseff_dVb = 0.0; 
          }

          if (Vdseff > Vds)
              Vdseff = Vds;
          diffVds = Vds - Vdseff;
          here->BSIM4Vdseff = Vdseff;
          
          /* Velocity Overshoot */
        if((model->BSIM4lambdaGiven) && (model->BSIM4lambda > 0.0) )
        {  
          T1 =  Leff * ueff;
          T2 = pParam->BSIM4lambda / T1;
          T3 = -T2 / T1 * Leff;
          dT2_dVd = T3 * dueff_dVd;
          dT2_dVg = T3 * dueff_dVg;
          dT2_dVb = T3 * dueff_dVb;
          T5 = 1.0 / (Esat * pParam->BSIM4litl);
          T4 = -T5 / EsatL;
          dT5_dVg = dEsatL_dVg * T4;
          dT5_dVd = dEsatL_dVd * T4; 
          dT5_dVb = dEsatL_dVb * T4; 
          T6 = 1.0 + diffVds  * T5;
          dT6_dVg = dT5_dVg * diffVds - dVdseff_dVg * T5;
          dT6_dVd = dT5_dVd * diffVds + (1.0 - dVdseff_dVd) * T5;
          dT6_dVb = dT5_dVb * diffVds - dVdseff_dVb * T5;
          T7 = 2.0 / (T6 * T6 + 1.0);
          T8 = 1.0 - T7;
          T9 = T6 * T7 * T7;
          dT8_dVg = T9 * dT6_dVg;
          dT8_dVd = T9 * dT6_dVd;
          dT8_dVb = T9 * dT6_dVb;
          T10 = 1.0 + T2 * T8;
          dT10_dVg = dT2_dVg * T8 + T2 * dT8_dVg;
          dT10_dVd = dT2_dVd * T8 + T2 * dT8_dVd;
          dT10_dVb = dT2_dVb * T8 + T2 * dT8_dVb;
          if(T10 == 1.0)
                dT10_dVg = dT10_dVd = dT10_dVb = 0.0;

          dEsatL_dVg *= T10;
          dEsatL_dVg += EsatL * dT10_dVg;
          dEsatL_dVd *= T10;
          dEsatL_dVd += EsatL * dT10_dVd;
          dEsatL_dVb *= T10;
          dEsatL_dVb += EsatL * dT10_dVb;
          EsatL *= T10;
          here->BSIM4EsatL = EsatL;
        }

          /* Calculate Vasat */
          tmp4 = 1.0 - 0.5 * Abulk * Vdsat / Vgst2Vtm;
          T9 = WVCoxRds * Vgsteff;
	  T8 = T9 / Vgst2Vtm;
          T0 = EsatL + Vdsat + 2.0 * T9 * tmp4;
         
          T7 = 2.0 * WVCoxRds * tmp4;
          dT0_dVg = dEsatL_dVg + dVdsat_dVg + T7 * (1.0 + tmp2 * Vgsteff)
		  - T8 * (Abulk * dVdsat_dVg - Abulk * Vdsat / Vgst2Vtm
		  + Vdsat * dAbulk_dVg);   
		  
          dT0_dVb = dEsatL_dVb + dVdsat_dVb + T7 * tmp3 * Vgsteff
		  - T8 * (dAbulk_dVb * Vdsat + Abulk * dVdsat_dVb);
          dT0_dVd = dEsatL_dVd + dVdsat_dVd - T8 * Abulk * dVdsat_dVd;