John, You've hit the nail on the head: I'm trying to usurp a Cadence flow for a high frequency continuous time analog design. As such, I have a lot of problems to overcome, but a rough order looks something like:
1) download/build GSchem 2) find/build symbol library for TSMC XXX 3) find a way to convert netlist to Spice format compatible w/TSMC parameterization (W,L,f,m,Corners) 4) find a way to do Monte Carlo, even if only with deltaVTH numbers from Pelgrom or Kinget . . . 99) find/build robust open source LVS flow Yesterday I did #1. Today I'm working on #2. I would love to get a copy of the OpenIP library, thank you. Are you saying that #3 is going to be harder than just downloading/building GNetlist? Many thanks, Dale Douglas http://www.linkedin.com/pub/2/184/925 -----Original Message----- >From: John Doty <[email protected]> >Sent: Mar 8, 2009 12:05 PM >To: gEDA user mailing list <[email protected]> >Cc: [email protected] >Subject: Re: gEDA-user: GSchem in CMOS Analog IC context? > > >On Mar 8, 2009, at 7:22 AM, Stuart Brorson wrote: > >> Hi -- >> >>> Has anyone successfully used GSchem in an CMOS analog IC context? -- >>> I'm looking at a plain-vanilla +MIM TSMC CMOS process at the ~ 0.18 >>> to 0.35u node. Has anyone built symbols for the typical TSMC nodes >>> (parameterized NMOS,CMOS,resistors with appropriate sheet resistance >>> and tempco)? > > >Dale, assuming you're using SPICE, the question is whether the >currently maintained gnetlist back end (spice-sdb) understands the >parameter names. A regular resistor symbol should work fine with the >right attributes. > >So, Stuart, does spice-sdb know how to transfer attributes to >parameters in the following syntax (ngspice)? > >General form: > > RXXXXXXX n+ n- <value> <mname> <l=length> <w=width> <temp=val> > + <dtemp=val> m=<val> <ac=val> <scale=val> <noisy = 0|1> > > >> >> Peter Kaiser in Germany has done some chip designs using gEDA. Here's >> the website he put up recording some of his tips, including some >> symbols for instantiating devices: >> >> http://www.easyasic.com/ >> >> You might try contacting him in person if you have questions. His >> e-mail addr is on his website. >> >> John Doty has also done mixed-signal designs using gEDA. He has >> published papers on his work, and has written an interesting gnetlist >> back-end, all of which he has posted on his website. I didn't see any >> schematic symbols on his website, but here's a link: >> >> http://www.noqsi.com/home.html >> >> John is very active on the e-mail list, so I expect that he'll turn up >> to provide more info to you soon. > >Gotta be less predictable ;-) > >Dale, I've done several design variations on my delta-sigma CCD >chains using 350 nm TSMC. However, I haven't gotten into careful >modeling of the resistors. I use very few resistors in these designs, >always in noncritical places. Gains are set by capacitor ratios. > >If you're interested, I've been working on symbols for professor >Ikeda's OpenIP (http://research.kek.jp/people/ikeda/openIP/). I can >send you an alpha version of that library if you wish (you get to >check them, as I've only used a subset), and I can answer specific >questions if you can't read the Japanese documentation. > >John Doty Noqsi Aerospace, Ltd. >http://www.noqsi.com/ >[email protected] > > _______________________________________________ geda-user mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
