Constant current drive for LEDs

Just happened to find this link on Hack-A-Day this afternoon and decided to post it because of a recent discussion here on the forum.

http://www.pcbheaven.com/userpages/LED_driving_and_controlling_methods/

...Tiger

Good Tutorial, I like it touches on Pulse-Width Modulation (PWM) for controlling brightness of the LED

The tutorial here will certainly add to what I already know, thanks for post Tiger


EDIT: For the mathematically challenged like myself I found his On-line LED Calculator. Although I have seen allot of these types of On-line Calculators but this would seem to be one of the better ones. I'm assuming this Calculator incorporates all the MATH he discuses in his tutorial on Limiting Resistors 

On-Line Calculator: http://www.pcbheaven.com/drcalculus/index.php?calc=leds