Laptop LCD Controller is Getting very hot

I've extracted a 17 inch lcd from a hp pavilion 6. I knew that the lcd is fine so i ordered a Controller on ebay. gave them the model number and here it is.
Now i don't have the proper adapter for it but I use a PC power supply the controller is rated for 12V 4A and the power supply's rail that I'm using is 12V 15A one yellow and one black wire. - and + wires are correctly soldered checked 5 times :D.

When i turn the controller board on, the chip is actually cold but after I start sending signals to the lcd it heats up really fast to the point I feel uneasy with the finger on.

Is this normal or am I doing something wrong? If anybody has experience with those controllers please help.


you are pumping a HUGE amount of amps into it. the controller is pulling more amps then it needs. should be fine as long as it doesnt get to hot. anything above 80C is a no go.

Yep I knew one of thouse days I am gonna frie something... so I failed basic electronics...

To start from beginning xD if a device is rated for 2 Amps and the source can deliver more is it gonna pull more from the source if its availabe?

yeah to a degree. if a device is rated for 2 amps then you could deliver ~2.75 amps before it pulls more current then necessary. but if you provide it 100A then it wont make much of a difference then 20A. if my understanding is right.

No. If it is 12V 2A rated, you need a power source that supplies 12 Volts and can supply at least 2 Amps. The ability to supply 15A is perfectly fine.

If it's running too hot just put some thermal paste and a heatsink onto the black chip in the center. Another chip that could be overheating is the little one in the upper-right corner which I guess could be a voltage regulator (or a power transistor).

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So I was right. Thx for the confirmation and yes I'm gonna stick on a heatsink if nothing else it's gonna improve the lifespan :D.

That is not how power supplies work.

Most of the Electrical devices we use are constant Voltage devices. They need or supply a specific constant Voltage. The current the devices draw / supply are variable and dependent on the need of the device. The rated currents that are printed on the devices tells you how much a power suppy can deliver at most before the voltage starts to drop or in case of a consumer how much current it will draw at the maximum.

So in this case the LCD controller might draw up to 4Amps and the power supply can deliver up to 15Amps. It will not however push 15Amps into the LCD controller.

Considering however that 4A *12V = 48W that power has to go somewhere. And apart from light energy that gets put out the display, the rest will be converted into heat. So its not really unusual for it to heat up even beyond a temperature that would be to hot to touch. Although a heatsink is never a bad idea. I bet that the manufacturer left it off since it just about worked without it and saved a few cents even though it would have been better to use one.

Also allot of devices have thermal shut-down circuit integrated that prevent them from getting to hot. So if they are reaching this point they will usually shut themself off until they cool off, and then back on again.

Now that this is sorted out, I can continue my project. If its going to be successful I will post it as a Build log :D