How to make your own High Power LED Driver

[sy272004]

hey guys. anybody got how to for high power leds? i found some cheap led drivers at dealextreme but wondering how hard is it to make one yourself, how hard to get components. or just get it already made since its not worth the time and money to make one?
doesnt matter which led 1W 3W or 50W

searched google but didnt find info on how to make one

[azdave]

hey guys. anybody got how to for high power leds? i found some cheap led drivers at dealextreme but wondering how hard is it to make one yourself, how hard to get components. or just get it already made since its not worth the time and money to make one?
doesnt matter which led 1W 3W or 50W

searched google but didnt find info on how to make one

I've played with some fixed output ones from Dealextreme but it is very hard to reset the current if it happens to not be what you need. Most of the simple LED drivers on Dealextreme are for flashlight applications so using them at 12 volts is not a good idea.

The simplest adjustable driver still has to be the one the VanIsleDSM found for around $2-$3. The AMC7140 needs only one small resistor selected to be a complete driver package. Current can be set up to 700mA output and has a PWM on/off feature (you can ignore if you want). It also drives many, many LEDs in series (up to 50 volts worth of Vf) if you have the input supply voltage to support it so it also works for home use. The only disadvantage I see is that you have to work with SMT size tabs to solder it up.

[sy272004]

link?

i found this
http://www.micro-bridge.com/data/ADD...User_Guide.pdf

[azdave]

link?

i found this
http://www.micro-bridge.com/data/ADD...User_Guide.pdf

That is a pre-made board using the AMC7140 but not really what you want.

Here is VanIsle's review and if you search you'll find plenty about the driver here in the LED forum.

http://www.hidplanet.com/forums/viewtopic.php?t=42096

[sy272004]

ok. almost fried my brain reading through that.

can i get all parts that are needed from you?


http://www.besthongkong.com/product_...roducts_id=795 =P~
what you need to drive this thing?


i guess this will work too
http://www.besthongkong.com/index.php?cPath=19_51

[azdave]

ok. almost fried my brain reading through that.

can i get all parts that are needed from you?


http://www.besthongkong.com/product_...roducts_id=795 =P~
what you need to drive this thing?


i guess this will work too
http://www.besthongkong.com/index.php?cPath=19_51

I do have parts for the AMC7140 drivers.

Those multi-chip LEDs you linked could not be fully driven in series by a normal driver using 12 volts since 4 x vF is more than 12 volts. If you ran them in parallel (not recommended) you would need a driver that could supply 4 x the drive current. You would need a boost driver to make up the extra power required to run all 4 die in series.

The drivers you list are usually good for up to three white LEDs with 12 volt input.

[sy272004]

what about running 2 drivers to power 2 chips per each driver?

Dave, how much would parts for driver cost? whats included?

any pictures how everything supposed to be connected? im better with pics then drawn diagrams

[russgvrs]

I would recommend the lm317t for running 2 in series as the amc7140 shouldn't drop more than 1.5v. Plus it's a to220 package and easier to solder and heatsink. It's around $3 with set resistor.

[sy272004]

um little confused with your info. pictures are better explanation for me

[azdave]

I sell the AMC7140 with a resistor for about the same cost as a LM317T. The bigger LM317T is easier to work with since it's not so tiny but seems harder for people to set up with resistor choices.

Yes, The AMC7140 works best when it doesn't drop more than 1.5 volts comparing input to output so normally 3 white LEDs in series is good choice.

I'll try to find a pic of one of my setups but they are not hard to wire as they have few connections.