Driver that can handle 2x 10 high-power (1w) LED's

Forum 2005-2010 (read only) Hardware Interfacing
1

Hello,

I am new to this forum, and new to the Arduino in general. I'm interested in using the arduino to control 10 white 1W LED's and 10 amber 1W LED's, lighting up my apartment.
[ch960]

  1. What I really want is to connect each of the groups of LED's in serial, as I do not need individual control over the LED's. I guess this would require a driver that could handle two channels of about 3,5amps, but the only drivers I can seem to find are ones like ULN2003 Darlington driver, maxing out at 500mA. Any suggestions to what I could use?

  2. I will spread the LED's out over about 4 meters (13 feet). I understand to dim the LED's I will have to rapidly switch current on and off, using a PWM-pin into the driver. Will this cause problems over such a long distance?

Bless :slight_smile:

2

You might think this is an easy project but it it not.

A white LED requires about 3.5V so 10 in series needs at least 35V to drive it. Also you can't just switch it on you need to make a constant current supply. Look at these two links:-
http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1234273497

http://www.instructables.com/id/Circuits-for-using-High-Power-LED_s/

http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1824&appnote=en012124

Will this cause problems over such a long distance?

Yes radiated emissions will take out radios for quite some distance. Also due to the wiring capacitance you might not be able to switch as fast as you need to.