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By braxtron
#165556
Hi all. I've come up with a constant-current LED driver that can handle up to 1A and drive multiple LEDs with PWM. I've made a couple prototypes (Sparkfun Arduino ProMicros were involved) and would like to see if anyone is interested in using them for a project or two. Maybe we could get SparkFun to be the US distributor ;)

Here are the main features:
*Input voltage range 3V-22V
*200mA to 1A constant current output (user-selectable)
*EN/DIM input for Enabling and PWM dimming
*Ultralow shutdown current (40nA @ 5V input)
*Under-voltage lockout

Here's the website: http://braxtron.com

Please feel free to either post here or contact me via email (info[at]braxtron.com) if you have any questions.
User avatar
By Ross Robotics
#165572
If you need some testers, I would be happy to put them through their paces. Email me trevor@rossrobotics.com
By braxtron
#165869
I just ran some tests with one Cree XM-L T5 LED. I'll do some more with 2+ LEDs in series, as the data sheet suggests that'll be more efficient:

200mA output
3.7Vin = 89.6% efficient (2.69Vout)
8.0Vin = 76.6% (2.73Vout)
10.4Vin = 73.7% (2.75Vout)


1000mA output
4.1Vin = 72.2% (2.73Vout)
8.0Vin = 69.4% (2.85Vout)
10.4Vin = 67.2% (2.86Vout)