> Followed a link from a Luxeon LED application page and ended up at > this patent. Wow. That may be the most vitriol I've ever seen come from you, Russell. Not that I disagree... Essentially, they are attempting to patent the use of a constant current regulator to drive LEDs. A part search at Linear.com for the chip they cite yields this doc http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1042,C1031,C1061,P2079,D4570 Unwrap link as needed. Published well before the date on their patent application. Let's hope the system works. Mike H. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist