Electronic – COB LED Dimming via Poentiometer

cobdimmerdimmingled

I want to create a dimmer for high power LED light's i'm building for video work. I'm using CREE CXB3590 chips, which have run at 36V with a forward current of 3.6A. I am powering these through a 150W 12V power adapter, hookued up to a step up converter that has a separate pot for current and voltage regulation. I want to create a dimmer for these lights, and I would like to do it as simply as possible. I have a box of assorted resistors and some 100K pots, so the question is, can I use these resistors and a 100K pot to dim my lights, and if so, how would I go about doing so? I don't know how the math works, but I can follow a schematic so I'd appreciate any help the community could offer. Thank you!

Best Answer

I'd recommend you 86 the 12V power supply and boost driver.

Use a $40 Mean Well HLG-150H-36 CC Driver. It has a pair of DIM wires where you connect a 100K pot to set the current. I use 10 resistors and a jumper to select the current.

I have to question your use of the CXB3590.

  1. The typical forward voltage is 38.5V @ 3.6 Amp.
  2. Running it at 3.6 Amp makes thermal management very difficult.

I would only use a CoB if size is an issue. If you were to use some $4 1200 lumen Bridgelux EB Series Gen 2 strips you will get a much better lumens per watt ratio and thermal management would not be needed. Cost would be less per lumen but would take up about a sq. ft. of real estate strips are 11" x 1". Light uniformity would be better with the strips.

The max lm/W for the CXB3590 is 145 lm/W. The strips are 180-175 lm/W. Heatsinks and fan for the CXB3590 will add considerable cost. The CBX3590 will also loose efficiency if you do not keep the temperature down.