> Harold, > > I looked @ LT1370 it looks very good. So you used maxim part together > to make it constant current LED application right? > I like to know what maxim part you used if possible. > MAX4073TAUT-T . Also, I added a zener diode from the top of the LED (current source output) to the amplifier output so, should the LED open, the amplifier output would be pulled up as the boost converter output went up. This prevented exploding capacitors. Harold -- FCC Rules Updated Daily at http://www.hallikainen.com - Advertising opportunities available! -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist