--0__=85256AC7004870418f9e8a93df938690918c85256AC700487041 Content-type: text/plain; charset=us-ascii A 2 transistor current mirror should suffice. Scott F. Touchton 1550 Engineering Manager JDS Uniphase Anand Dhuru cc: Sent by: pic Subject: Re: [OT]:Constant Current Source microcontrolle r discussion list 09/14/01 09:16 AM Please respond to Anand Dhuru Hi guys, I need to have a constant current of 1uA flowing thru' two terminals in a circuit. What would be the easiest way to do this? One way I know would involve a 3 pin voltage regulator, with the (normal) ground connected to the output thru' a resistance instead. Would this approach work for a current this small? Or is there an easier way to do it? BTW, the actual amount of current does not have to be very precise. Just in that magnitude, but should be pretty stable. Any advice would be greatly appreciated. Regards, Anand -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! 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