COB (chip on board) led 50w warm white


I will for sure bro thanks for all the help today


Anytime! Let me know when you get it, or need anything else.


I usually go to trc. It’s not the best, but reasonable. If you find that tool please let me know. It will be a lot easier than scrolling and then guessing that I’ve covered all of them that will work.


Ok so I couldn’t resist but to mount the cob on the heat sink and solder the fan +- and power cord +- to the cob on the heat sink. It looks like this

Did I solder the correct +- @dbrn32


So I had a old laptop driver that was 19.4v it boosted the fan power and light blinked twice and that was it, probably not enough juice to power it but the fan was full speed, and then calmed down to a low speed like a laptop would :rofl::wink: probably next paycheck getting the Correct driver would help lol

I’m also worried about that black mark over the cob it looks like it was used when I got it? Over heated maybe


Well not sure. You’re gonna need a separate power supply for the fan.


Really? I couldn’t just get the driver large enough to power them both? @dbrn32


I do have the correct power supply for the fan! But it wasn’t enough juice to power the cob haha!


Driver for fan is 19.4v (3.34A) it’s an old laptop driver actually and it worked like a startup of a computer high speed then low speed constant it is also cc/cv


Like I said, be very careful with constant voltage power supplies. They may not have a specific current limit so you might end up getting 10 amps through your COB and burn it up. COBs really should have constant current and the voltage will go to whatever it takes to get that current through the COB.

If you had a 36 volt constant voltage supply that could source 850 ma or more, you could make a constant current limiter with a LM317 1.5 amp voltage regulator and a 1.4 Ohm resistor from somebody like Digikey. That regulator is only about 58 cents and the resistor is less.


Nope this cc/cv driver from my laptop was 3.34A so no worries there it wasn’t enough to power the cob. So I’ll remove the solder form the cob and rewire the laptop driver for JUST the fan, and buy the correct driver for that cob and see how things go.


Honestly, I wouldn’t use that either. The efficiency loss on that will be more than the fan draws.

Do you have any small dc power supplies laying around? Like a battery charger or for some appliance you don’t have anymore? You just have to make sure the current rating for the fan is less than what the power supply has available. Something between 5-12 volts preferably, the higher the voltage the faster fan will spin.


Yes an AC/DC adapter, dell laptop power block

output 19.5v
Power 65w

this is for the fan. I want it to work I’m not worried about efficiency I’m sure it’s efficient enough. Efficiency rating is (V)

It did not work to power BOTH the fan and cob. The cob alone needs 36v correct as you gave me a meanwell npf-40d-36 to use for that driver, this did not include the fan.

Fan is Delta Electronics Model# AFB0712HHB
DC12v .45A

So fan barley uses anything.


You REALLY want to run that fan with 12 volts or less. 19 volts would burn it out very quickly.


You’re going to be overclocking fan, will probably lead to premature failure. Like I said I would look for something 12v or less.


Jinx lol. See @AmnesiaHaze, we’re not far off on this.


@dbrn32 and @1BigFella

I do have to agree, to disagree. Only because, when I powered the circuit up, the fan was at blazing speed like when you first start up your computer! Then it switched to a very low speed which was the sound of a normal operating fan on a computer. Utilizing the same origin (PC) it is a PC fan driven by a PC(laptop) block. Now the fan can only take as much juice as it gets I understand that. But if I could upload my video I would but you cannot upload videos in here. I’m telling you it went from that loud fan speed when you first boot up your computer, then it went to a slow and steady speed like the computer was running! So it stays at 12v after the 19v peak on startup. I hope you guys are getting what I’m saying lol. The power block(laptop driver) was thinking it was booting up a PC!


I have a good eye(ear) when it comes to fan speed. I know that the fan was not overclocked! It had the peak boost of 19v on startup then idled down to 12v constant like a computer!:+1::wink::sunglasses:I was SCARED at first but I let it do it’s thing I wouldn’t care if it melted lol I want to learn, but it idled down, don’t worry everything is gravy. Let’s try this out and see if it works, now I just need a proper driver for my COB, and we are off to the horse races :racehorse:


It could be that your power supply charged up to 19 volts unloaded and then dropped to 12 volts once it was loaded by the moving fan. It would be easier to see what really happened if you used a voltmeter.


I will be willing to do this if you guys can give me some time. I have some lasanga to eat :drooling_face: I’ll be right back give me 30-45 mins @1BigFella