Hello,
I am trying to implement a filter which has a sinc(f) frequency response or in otherwords, a rectangular pulse impulse response. I have implemented this with
Code:module myflt(in, out)
output out;
input in;
electrical in, out;
parameter tflt=10n;
electrical integ, dly;
analog begin
V(integ) <+ idt(V(in), 0.0, 0, Voltage)/tflt;
V(dly) <+ absdelay( V(integ), tflt);
V(out) <+ V(integ, dly);
end
endmodule
This works fine for transient analysis. However for PSS analysis (spectreRF) I get hidden state complaints. So I tried adding
Code:(* instrument_module *)
before the module line. That got rid of the complain and gave non-convergence. Then I tried adding:
Code:if( ! analysis("pss") ) begin
// original contribution statements here
end
because I really don't care if this module is active during PSS but it is nice to not have to change netlists between PSS and transient sims. However, that also fails with a zero jacobian at the integ node (integrator output). That says to me that the analysis() bit isn't really doing what I thought.
Any suggestions?
Thanks
-Dan