hi all, I'm looking for a cheap (and by extension simple) circuit. i have a special pot (Piher's 10mm hex PT-10) that can't be changed. the pots can be physically changed but i have to use this type. the series has a 150mw power rating, with resistances of : 100,150,200,250,500,1k,2k,2.5k,5k,10k,20k,25k,50k,100k,200k,500k. i have a 3.3v source (tight), with 750-1000ma available to play with. i want to drive 15-30 LEDs in parallel, each pulling 19ma. so a total current of ≈ 375ma - 600-650 would be nice; but i could live with a cap of 500ma. i need to be able to take them from (as close to) off to (as close to) full brightness as i get get, via control of the Phier pot. the Phier pots can rotate about 250°, and i can use about 180° (about 75% of its resistive range). full brightness would be the LEDS seeing 3.1-3.3v does anyone have any sugestions as to what setup to use to supply the current i need? id take ideas above 350ma. EDIT: forgot to mention id like it to in/decrease linearly, like one would see with voltage dividing pot (that was of cource non-logarithmic in style).