In my searching I came across an outstanding site covering the theory behind all tpyes of voltage regulators: http://www.mohawkc.on.ca/dept/electro/staff/chanh/EE451/ppframe.htm I think I'll take a stab at putting together a boost regulator... BAJ -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads