On Fri, Mar 6, 2009 at 6:09 PM, Yamazaki R2 <[email protected]> wrote: >> Message: 8 >> Date: Fri, 6 Mar 2009 21:39:03 +0000 >> From: r <[email protected]> >> Subject: Re: gEDA-user: Using .global statements in GNUcap and mult >> transistors >> To: gEDA user mailing list <[email protected]> >> Message-ID: >> <[email protected]> >> Content-Type: text/plain; charset=ISO-8859-1 >> >> 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. > **WOW** I'm an idiot I can't believe I didn't think of that! I'll just add a wrapper script for my simulations to preprocess the netlist and merge the transistors with the m parameter. That should be a quick and easy solution until gnucap automatically does this for you. If anybody is interested I can post the script on the mailing list for everybody else to use. I'll probably just use perl for regex capability.
_______________________________________________ geda-user mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
