@User, I am extracting a pex netlist in sky and it has these NWDIODEs. It seems like spectre has convergence issues if these diodes are present. If I remove these diodes, I will get the spectre sim results. Do you know the reason behind this? Thanks

There is no "nwdiode" (that I am aware of). Where are you getting these device models from? There is a device

sky130_fd_pr__model__parasitic__diode_ps2nw

.

Thanks for the response, now I am using the spectre models from src-nda.

I cannot be of much help with the spectre models, since I don't have spectre. For what help I can give, we should be using the #nda channel. One thing that looks odd to me, though, is that the netlist has "A" and "P" parameters, where the model (diode level 3) has "area", and I'm not sure that the model even understands perimeter.