gmadhavareddy
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Hi, I want to change the model of Schottky diode which is avilable in Cadence ahdlLib. I want to know the $Vt and what $ indicates in veriloga code?
Vd = V(vanode, vcathode); `ifdef __VAMS_ENABLE__ Id = I(<vanode>); `else Id = I(vanode, vanode); `endif // intrinsic diode. if (Vd < -5*n*$vt) begin if (Vd == -bv) begin I(vanode, vcathode) <+ -area*ibv; end else if (Vd > -bv) begin I(vanode, vcathode) <+ -area*is; end else begin I(vanode, vcathode) <+ -area*is*(exp(-(bv + Vd)/$vt) - 1 + bv/$vt); end end else begin I(vanode, vcathode) <+ area*is*(exp((Vd - rs*Id)/(n*$vt)) - 1); end
I(vanode, vcathode) <+ gmin * Vd; // capacitance (junction and diffusion). if (Vd <= fcp) begin Qd = tt*Id + area*cjo*phi*(1 - pow((1 - Vd/phi), (1 - m)))/(1 - m); end else begin Qd = tt*Id + area*cjo*(f1 + (1/f2)*(f3*(Vd - fcp) + (0.5*m/phi)* (Vd*Vd - fcp*fcp))); end I(vanode, vcathode) <+ ddt(Qd);
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