Need help to find IC

[nicola]

Hi, i nedd to find the IC in the picture attached. Come from a Notebook powersupply (Lite on power supply). The PS is a classical Flyback converter. This IC i think is the controller.

Thanks

[tomelec]

Re: Need help to find IC

It´s hard to read the label on the photo. I bet you can read it at good lighting ...

[nicola]

Re: Need help to find IC

This is the best pictures i have. It's very difficult to capture a better pics. I thinks the code is like TA703S

[tomelec]

Re: Need help to find IC

What is written in the second line?
What is connected to which pin of the IC? Any other controller related devices on the board?
I think you need to get some more information, in order to find out what that thing is and what it is supposed to do.

[nicola]

Re: Need help to find IC

The 2nd line is something like "NAE" and last line is "SYB".
I will check the connection later. This is the only IC in the board.
Like any other classic flyback there are an n-ch mosfet (tested and ok), output diode (tested ok), diode bridge (tested and ok), bulk capacitor (after the bridge) and an optocoupler (tested and ok).

[nicola]

Re: Need help to find IC

With good probability the ic is a TEA1733 from NXP. In the App note AN10868 the output diode and n-ch mosfet have the same part number of the my power supply.
Unfortunately i can't find any reference on how this IC is marked on top side

[nicola]

Re: Need help to find IC

Checking the connection and searching on internet i found that the ic is probably an On-Bright electronics product. At the moment i know only that pin1 is GND

http://www.on-bright.com/cn/english/index.htm

On-bright produce many SMPS IC controller so it's not easy to find the right one

[nicola]

Re: Need help to find IC

Under different light i see this code:
TA703S
TKHAE
SYB

but nothing on internet correspond to this code

[kasfamily]

Re: Need help to find IC

Show the full picture the power supply board and assign it a name - the model power supply

[Agent24]

Re: Need help to find IC

It looks like it has flux residue on it. Try cleaning it with some alcohol or such, then you may find it easier to read...

[nicola]

Re: Need help to find IC

Thanks for your reply. Here is attached the PS model.

[kasfamily]

Re: Need help to find IC

LTA703S Fairchild http://finance.yahoo.com/news/power-...123000979.html

[Agent24]

Re: Need help to find IC

Did you check start\run capacitor?

[nicola]

Re: Need help to find IC

Thanks very much for the reply.
I can't find a datasheet of LTA703S and where to buy.
Does exist an alternative?

Thanks again

P.S. Yes the caps are OK

[kasfamily]

Re: Need help to find IC

Need a good photo and will have an alternative, check resistor 3R3

[nicola]

Re: Need help to find IC

Please check the pics attached

[kasfamily]

Re: Need help to find IC

May be alternative SG5851

[nicola]

Re: Need help to find IC

Thanks very much

[nicola]

Re: Need help to find IC

The SG5851 is obsolete so is there another alternative?

[kasfamily]

Re: Need help to find IC

Look for the evening, and you checked the 3R3 ?