I want to do some modifiaction of BSIM3v3 model MOS equations in Spectre.
Can anybody please tell how it can be done in Spectre.
You can't do it directly, because the model is implemented in C. However, I believe there are some Verilog-A implementations of the various BSIM models "out there" which you then may be able to take and modify to suit your needs.
Changing the model equations is not for the faint hearted - I presume you have a good reason for doing this? Can you not achieve the same end by altering the model parameters rather than the equations themselves?
Thanks Andrew for your suggestions