COB LED Constant Voltage Driver Selection Tool

I’ve had a number of requests to put up a constant voltage version of my COB LED Driver Selection Tool so I drafted one up today. Please see the notes at the bottom of this post for some important additional info. Also, if you’d like to see any COBs added, let me know which ones and I’ll see if I can include them.


  1. Select a COB from the dropdown.
  2. Enter the quantity of COBs.
  3. Select a drive current.

The spreadsheet will calculate the voltage of your circuit as well as the total current and highlight all of the Mean Well HLG drivers that are compatible with the parameters you entered. If the voltage of your COB(s) falls within the rated voltage adjustment range of a driver and your total current draw is less than that driver’s rated current , that driver will turn green, indicating it is a match. This calculator assumes all COBs will be wired in parallel so voltage is the same throughout each of them.


1. All drivers are “A” type with built-in voltage adjustment potentiometer.

2. Mean Well HLG drivers are considered “constant voltage plus constant current” (CV+CC). This means that if your COBs try to pull more current than the driver is rated to produce, the driver will switch to constant current mode and hold steady at the max current it can provide. It will distribute this current to the COBs it’s connected to, and vary its voltage output to match the COBs’ forward voltage. As long as the COBs’ forward voltage does not dip too low as a result of the current it’s receiving, this functionality will allow you to use slightly smaller drivers than you actually need.

E.g – 4x CLU048-1212s pull 5.6A at 1,400mA. Would this still work on an HLG-185H-36A which is only rated for 5.2A? The answer is yes. The COBs will pull the full 5.2A from the driver, kicking it into constant current mode. 5.2A divided by 4 COBs will be 1,300mA each. At 1,300mA, these COBs should produce a voltage of 35.8V, which is within the constant current range of the HLG-185H driver (check spec sheet for this range).

3. All driver specifications are pulled from the official specification sheets. Some of these specs are underrated, so if a particular driver is just slightly out of range, check the “Reports” section of the Mean Well data sheet package for that particular driver to see if it may still work. E.g. – rated current on an HLG-185H-36 is 5.2A on spec sheet, but the test unit on their report page was able to reach 5.9A.

4. Rated power is derived from nominal voltage x rated current (HLG-185H-36A = 36V x 5.2A = 187.2W)


  1. Could add the luminous and the seoul semiconductor chips, but they are 50 volt chips just like the citizen 1818’s though. They are all fairly the same voltages though it seems.

    • LEDGardener

      March 12, 2017 at 10:34 pm

      Sure thing. Ill try and track down some info on the Seoul Semis – I have the luminous data sheets somewhere already.

  2. just a heads up you may want to make some of the cells orange like for example for 50V chips where they are operating ove rthe stated 52V max of a -48A driver.. most of these drivers go up to 53.5-54V (see test report not datasheet for actual test data)

    great site btw!

    • Thanks Cobby! I did touch on this in my third note at the bottom of the post but making these instances orange is a great idea.

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