On Thu, Mar 5, 2009 at 2:23 AM, al davis <[email protected]> wrote: > >> > >> > The Gnucap behavior is consistent with Hspice and Spectre. >> > At least that is what I have been told. I don't have >> > access to them to check it out. >> >> That's incorrect. Both Spectre and Hspice treat devices with >> m>1 as single entities. > > ok .... maybe you can help solve this.
Well, I'm not sure. I don't know how it is implemented in these simulators. I guess these guys have simply modified the models (they have modified quite a few other things there so I guess they wouldn't have minded adding "m" parameter as well). > Also consider that there are a bunch of parameters that can be > probed. Some multiply, some divide, some are not changed. > There is no indication in the code of which is which. There > could be hundreds of parameters that could be probed. All that > is known is a name and the type (real, int, string, ....) that > it returns. There is no notion of across, through, or anything > that helps the decision of how to scale. Perhaps it could be done at the time of stamping the matrix - by multiplying all gm's by a factor of "m". Then all the probes would "just work". I have no idea how it could be done technically, though. BTW, some simulators preprocess the netlist and reduce parallel devices into a single device with an "m" parameter set. This gives a huge performance boost in extracted sims. -r. _______________________________________________ geda-user mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
