This is a gold mine for someone still in the learning phase of the EE world. I love it. http://www.web-ee.com/primers/Tutorials.htm These are only a few of the links (mostly pdfs): - Battery manuals - Lithium Ion Charging Requirements - PIC tutorials - OP AMP tutorials - Intro to CMOS and the like - I2C - Cell phone design - Intro do USB development - Digital filters - USB in a Nutshell There's probably something in there for everyone. Enjoy. -Mario -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist