Hi, Richard. > Have you tried looking up the manufacturers websites for models? TI & > Philips are pretty good & I'm pretty sure Fairchild also has them. Yes, I have. The probloem is that I need some relative older and semi-obscure parts with less probability of obtaining models from the manufacturer (if they still are in the business!). > If you need to extract a model from a sample part, it gets a bit more > difficult. Pspice has a model generator, but it's only available for > diodes in the eval version I use. That is the quid. I am able to obtain the datasheets so I would like to build the models from them. The problem I am facing is that I can't find correspondence between some of the parameters from the datasheets and the models. By the way, I use LTSpice/SwitcherCAD from Linear Tech. It is an EXTREMELY good SPICE simulator. And it is freeware. Regards, Carlos. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist