On Tue, 23 Feb 1999 09:27:41 -0500 Vincent Deno writes: >My current project requires very low power consumption (remote >control). > >Here's the fun part: There are 50 indepedant LEDs. "Low power" and "50 LEDs" don't belong together. At the least, use high efficiency LEDs. >The board space is very small (at best) and real-estate is hard to >come >by. I have therefore considered removing the current limiting >resistors >and controlling intensity via PWM alone. Any thoughts on this? It's a bad idea. If you can reduce the voltage the LEDs use to just slightly more than the LED and driver forward voltage, the power lost in the resistors will be small. > >Finally, it was suggested that I control the power of some ICs by >hooking >up their power lines to a small FET. The Shift registers are the >biggest >offender as far as power goes (everything else goes to sleep). CMOS shift registers will use very little power when the LEDs are all off. I don't think it will be worthwhile disconnecting the power to them. ___________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com/getjuno.html or call Juno at (800) 654-JUNO [654-5866]