Anyone built a high power LED driver?

[Madman Lighting]

This is an off the wall question but has anyone built a high current LED driver using one of the commercially available driver chips?

As a demo product or similar I was thinking about building one which would include etching a PCB. Yes, I know there's lots of them out there but I was just thinking about trying.

The other thing I was thinking about building was an adjustable constant current power supply. Not just for LEDs, but for a magnetic levitation experiment/project. I need to do more research but I think I'd need on the order of tens of amps at low voltage to make it happen.

Thanks!

-John C.

[macfrank]

This is an off the wall question but has anyone built a high current LED driver using one of the commercially available driver chips?

I've used the Max 1595 as a regulator. it's a very efficient 3.3V or 5V power supply, designed to run (among other things) white LEDs at up to 125ma directly.

I've used it as a regulator, using either a solar cell or 2 NiMH batteries (charged by the solar cells) as the voltage source. The output was a rock steady 3.3V to run an Atmel Butterfly board. This was a very low current requirement, but it was in an extremely hostile environment - the Mojave desert during the summer.

I made a PCB for it to fit an 8 pin DIP socket, but for this application, I just expoxied it to the underside of the solar panel. The whole thing survived for 160 days (until I picked it up). Internal temps reached 170F, with external ones (on the rock) reaching 150 - 160F.

I did test the 5V version of the regulator with just some white LEDs, and it works really well.

If you want a 30A! LED driver, they have the MAX16818

Frank

[Madman Lighting]

Cool, I mean ouch! HOT!

What were you monitoring with your board for that long?

There's lots of chip cos that that good power supply ICs, I just havent played with them much (yet).

Thanks.

-JC

[macfrank]

What were you monitoring with your board for that long?

I just thought it would be interesting to see if I could build a data logger that would work unattended for a long time in a very difficult environment. I measured three temperatures (one internal and two external) light level and battery voltage (I wanted to see how well the solar panel/voltage regulator/NiMH battery and charger system worked).

I was expecting it to only last a few weeks, and if it lasted all 160 days (that's how much storage space I had for the data) the LCD or some other component would have probably failed. It turns out that the box was pristine; a little bit of dust but otherwise OK.

One interesting effect I noticed is that the light sensor picked up the full Moon every 28 or so days.