islw2863

I want to build a very small switching regulator circuit that will : accept voltage in from ~2v to 6v output 6v and 1 to 2 amps this is intended to solve the annoying problem that a flashlight gets steadily dimmer from the moment you turn it on with fresh batteries until you can no longer tolerate its yellow and dim color and toss/replace the batteries. This circuit would maintain the same brightness until the batteries suddenly die. Many LED flashlights already use such circuits. I would like to provide such a circuit for my 4 cell incandescent bulb Maglite. The circuits used by the LED flashlights won't (I think ?) work for an incandescent flashlight. I have scoured the internet already searching for a circuit that is very small with low parts count so it can fit inside my Maglite to no avail. If you know of good small design that would accomplish please steer me in that direction. Thanks