Low voltage output.

[Vwolpert]

I'm working on a fridge. The control board is over $400. Fridge manufactur is AHT model ctb100. Number on control board BR84C-V1.1NE0661. Number on power supply is PSU-GA2. Power supply is part of main board. System should have 12vdc output but is only pushing 6.7vdc with 120vac input. I identified a blown capacitor. But there is a chip on the board looks like a voltage regulator or a mosfet. Has markings of "12"(printed vertical) and "A50X" (printed horizontal) any help on finding part would be great. Small guy in middle of picture with three legs.

 

[davenn]

hi there
welcome to EP

Has markings of "12"(printed vertical) and "A50X" (printed horizontal)

I suspect it really is X05V looks more like a V than an A ... can you really see a cross bar that would make it an A ?

so why do you think that particular part is faulty rather than, say, the IC to the left of it ?

and what markings are on that IC .... are there any other IC's / transistors on the board ?

 

[Vwolpert]

Unfortunately I don't know for certain which chip it is. But the leads and solder look discolored. No I can not see the bridge that would make it a "A".

 

[davenn]

Unfortunately I don't know for certain which chip it is. But the leads and solder look discolored. No I can not see the bridge that would make it a "A".

I cannot find any reference to A50 ( that doesnt mean that it doesn't exist )

But I did find a V50






again ..... and what markings are on that IC ??


Dave

 

[Vwolpert]

Where did you find that? I googled for awhile.
There's a lot on that chip. See attached picture.

 

[Bluejets]

I think you will have to show the board and essentially where you obtained the measurements quoted above.
Latest pic is a microprocessor.

 

[davenn]

There's a lot on that chip. See attached picture.

holy crap !! you are not wrong

it's an 8bit microprocessor
http://www.datasheetarchive.com.cn/dl/2a5d4ff31ee2c3416c6207d1a8b808ac83d409/P/EM78F661NASO16A

 

[davenn]

Where did you find that? I googled for awhile.

I googled SMD code V05

 

[(*steve*)]

You need to hope that the microcontroller is not damaged. Whilst you can possibly get a replacement, you won't get a replacement with the required program on it.

 

[Vwolpert]

Update: I ordered a new mosfet chip that looked damaged. I removed the old chip fitted the new chip after trimming the leads. And applied clean solder and it worked. Have an output of 12.2vdc. Thank you for all your help everyone.