louis@irisa.UUCP (Louis Chevallier ) (03/22/88)
I have 2 problems with sim2spice. Sim2spice is a Berkeley tool which generates a spice source file from a .sim file. I did not succeed in having it to produce the area and perimeter parameters for the transistors while the necessary data seem available. I also would like to know how I can take into account the width and length corrections on the transistors channel without modifying myself their L and W attributes within the spice file. Thanks in advance.
aes@whuts.UUCP (STEVENS) (03/23/88)
> I did not succeed in having it to produce the > area and perimeter parameters for the transistors while the > necessary data seem available. This is not a feature of sim2spice. Sim2spice will estimate these capacitances as ideal capacitances ("C" cards). It gets the values for these capacitances from the Magic tech file. > I also would like to know how I can take into account > the width and length corrections on the transistors channel > without modifying myself their L and W attributes within the > spice file. You can correct the length in MOS2 and MOS3 by adjusting the model parameter LD. You can adjust the length and width in MOS4 (BSIM) by changing DL and DW. In my personal experience, I have found that sim2spice is a waste of time for the following reasons: 1) As you mentioned above, it does not include areas and perimeters 2) It frequently causes transistors to be connected upsidedown, which if not corrected, will cause SPICE to crash 3) It does not make MAGIC subcells into SPICE subcircuits, and the resulting SPICE files are big and unruly. You end up wasting a lot of time massaging the sim2spice-generated file, when you could write your own SPICE file which will probably converge a lot better. --Andy Stevens AT&T Bell Labs, Whippany NJ aes@zeppo.att.com