This is the demonstration of powering 100W/34V  LED  from 12V power-supply .

there are 5 parts
1, 12V/7.4Ah UPS sealed lead acid battery

2, DC-DC step up converter [12v to 34V boost converter ]

3, constant current driver [ not include ]
   low cost LED driver from

4, LED 100w /34V with sufficient heat sink [ Processor heat sink  is a good option  ]

5,  LED Lens and Lens holder 

 video: old

video: new

crazypj made it!1 month ago

I thought I would check how flat the LED and heatsink were. They are terrible so I polished the back of LED with 400, 600, 1000 grit wetordry on a flat surface. It seems to reduced temps. I also used a copper heat spreader before the aluminium heatsink

100w LED 1.JPG100w LED 2.JPG
crazypj crazypj1 month ago

Oh, forgot to mention, the second pic is before I was finished removing scratches from 400 grit. The copper disc is a 'scrap' piece from motorcycle head gasket I made for my 1974 Honda. Copper has much better thermal conductivity than aluminium. I also used. thermal paste It used to be quite common to check the flatness of PC processors before fitting heatsink to get better heat transfer

Jestin_Cubetech (author)  crazypj1 month ago



great work.

reklrekl3 months ago
Nice thing.
But do i really need a current limiter to drive the LED and if yes, what transistors/resistors will I need?(32V, 3A) and do I need PNP or NPN transistors?
I think the step up converter is current limited at 6A, sso that would kill the LED...

Jestin_Cubetech (author)  reklrekl3 months ago

DC-DC 100W Constant Current Boost Step-up Module Power Supply.

pumpdatbass6 months ago
ever check temps on that thing? id be curious as to how much light it actually produced and how warm it is 2-3" from the led edge and center.
Jestin_Cubetech (author)  pumpdatbass6 months ago
9000 Lumens.
at least 40 deg C
TheGreatS8 months ago
Very cool. Or rather, due to 100 watts, hot? Still, a great instructable.

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