Too bright...

georges80

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Oct 23, 2002
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Location
Sunnyvale, CA
So, had a customer ask about a custom hyperboost configuration to drive a nominal 100W LED array.

Been doing some testing today with part of the challenge in keeping the 100W LED cool....

So, here's some pictures of today's fun for your viewing pleasure...

100W input power with about 94W going to the LED (yep, around 94% efficiency)

hb100w1.jpg


Power supply (input into the hyperboost) about 100W

hb100w2.jpg


Hyperboost on its heatsink - basically just sitting on some thermal pad against a hunk of aluminium

hb100w3.jpg


After 10 minutes, the heatsink temperature

hb100w4.jpg


and the hottest area on the hyperboost driver, pretty impressive considering it's just "sitting" on the thermal pad

hb100w5.jpg


Water getting pretty warm in the LED bath

hb100w6.jpg


The 100W LED array bolted down to a hunk of aluminium having a swim

hb100w7.jpg


cheers,
george.
 

PapaLumen

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UK
Nice efficiency! And thanks to that, nice board temp. What application is this going to be used for George? (if they dont mind you saying). That a bridgelux array?
 

georges80

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Nice efficiency! And thanks to that, nice board temp. What application is this going to be used for George? (if they dont mind you saying). That a bridgelux array?

I can't comment on the application or the specific LED array.

I think the supplied array is just a test sample, basically something I could use as a load to prove out the modified hyperboost capability. The array is running with a Vf of just over 30V driven at 3A. It is stupid bright :)

Yeah, I was very pleased with the efficiency, obviously having a close Vin to Vout is helping a lot. I did drop down the Vin to just under 20V (5A input) and was still getting a bit over 90%.

cheers,
george.
 

georges80

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Oct 23, 2002
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Location
Sunnyvale, CA
How low could you go with input voltage? What about 7.4 or 11.1v 14.8v?

It's a boost driver, so as input voltage goes down, input current goes up. For hyperboost I recommend a maximum input current of 5A. So based on that requirement you can calculate how much power can be fed into hyperboost for a particular input voltage.

Obviously if you tried to get 100W output from only 7.4V input that would mean over 100W/7.4V = 13A

So, assuming 5A max input, then for 7.4V the max input power would be 5 x 7.4 = 36W, for 14.8V it would be 5 x 14.8 = 74W etc etc.

cheers,
george.
 
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