Welcome to my white LED flashlight page. This page is about my white LED flashlight that I made using a pic as a driver IC and a luxeon emitter as the light source. These new luxeon units are outstanding. They claim a one watt dissipation with proper heat dissapation. What I have done is take a bank of 3 NIMH cells in series as the power source to the pic. This keeps the voltage low enough you can drive the LED's directly without a limiting resistor. The unfourtunate part when I was designing this was that I needed to sink about 100MA with the pic. Each pin is capable of only around 25, so I simply ganged a few of the pins together to come up with the required sink current capability. To see what pins are what simply look at the source. Also part of my design was the need to have a fully dimmable by software system, so there are 2 pins that are tied high by a 1k resistor. Short one pin to ground and it will either dim or increase the brightess depending on which one you short. I just used a few push button switches for this. On start up the unit is as dim as it goes. In this mode, I suspect that the unit would run for some months before requiring a recharge using decent capacity nimh cells. Its nice to just leave on in this mode as its easy to find in the dark. Then using the buttons you can increase the brightness. Once max brightness is reached, it simply restarts at the dimmest setting and will continue this cycle indefinitely given that the button is held down. Why a white led microcontroller controlled flashlight you ask? Well, with good nimh cells, it lasts so long, youd swear it was powered by a nuclear power source, the LED will virtually never burn out, its efficient, runs cool, is fully dimmable to whatever level you desire and its just plain cool to have something like that you built with your own 2 hands. If you have any questions, feel free to mail me at plappycf at netscape.net (asdf@asdf.com format, the typing of the addy keeps spam bots away.) HERE IS THE SOURCE CODE