This came out of a cheap Sams Club Rocky 220 lumen LED flashlight. The flashlight is made by Fuji Industries in Japan. It uses 6 AAA batteries 3S2P at 4.5 Volts and runs a Cree XRE-R2 LED. The driver looks like it could easily be modified (appears to have extra pads for resistors and capicators) but I have know idea how to do so.
The host has a reflector that has perfect throw for a LedEngin LZ1-10R400 IR emitter. This IR emitter runs about 1 A at 2.5V. (I swapped out this emitter with the LED on an old Dorcy 3AAA, used a dummy battery in one slot, and it worked perfectly.) I cannot get this driver to do the same. It works fine at 4.5 V, but when I drop the voltage down to 2.5, I get nothing to the IR emitter. I tried adding a resistor before the emitter to compensate for the 2 V drop, but still get nothing.