DVD Power Supply Repair TNY263P

Hi Joseph,

The repair of switching power supplies are very difficult and tricky. In some ways they are like a houses of cards. All the cards have to be in place and in good shape to do their jobs or the whole thing just falls down again. The failed chip could be the source of your failure but my experience is that the failed chips are almost always the victims and not the cause of the failure. I don't know if it will be of help but here is a link to the TNY263P Data Sheet.

https://www.power.com/sites/default/files/product-docs/tny263_268.pdf

I could not find an easy source for it but I will keep checking.  Once you have the chi out of the circuit it will be a good idea to check as many of the peripheral components as possible.

John

I was shown a great trick of fitting a mains voltage lamp of 100-150w in series with the mains supply when fixing these.

Rather than things going bang and smoke, the lamp lights ...

really useful tip.

Mark

Hi Mark,

This is an excellent technique for powering up a switching power supply after repair. Another is to use a variac and monitor the current as the voltage is slowly increased.

John

I've heard that before about using a light bulb, thanks for mentioning it. I am going to try it out on this repair. If anything I'll get some practice soldering and checking components if I can't track down the problem.

Thanks for info and the advice about smps being like a house of cards. Just knowing that is a great help. That pdf was very useful especially the power output table.

Joe

When I repair line-driven stuff I start with an appropriately-scaled isolation transformer, I have a collection

There are many ways to skin a cat but this is an idee fixe with me

Hi,

Anyone can share how to identify a burnt surface ic chip on a power supply board of dvd dvd player? I couldn't find the details.

Hi Nick,

Chips can go bad with no external indications. In this case the damage must be located by looking at voltage readings and how the chip functions. Occasionally the chip will show some outward damage like a discoloration or a burn. Sometimes the outer case will crack and the visual crack is an indicator. In extreme cases the top of the chip will be blown off by the failure.

Good Luck

John

Thank u for responding, i did recognized which ic chip was damaged but disfigured on surface till can't sight the part number or reference from it. I need to know how to find out which type of ic chip to buy for replacement. I can't post a pic here?

Hi Nick,

You can insert inline photos in the original discussion post, or in any comment, see here in the section 'Show me the editor tools' to see how to do this : How to Ask Questions using the Create Discussion tool

Most ICs look the same, so if there is no part number on it, it can be a guess (sometimes easier if it is a popular chip), otherwise there may be a reference diagram and parts list if you can find the service manual.

The service manual is normally not provided publicly, so it's just luck if you can find it via google, otherwise a service center may have access to that.

You might get lucky if it is the power supply board, if the part is well-known (but it might not be - you'll have to post a photo of that part of the board).

I think it may not be related to the topic of the title of the discussion? If it is not, maybe it's better to create a new discussion to avoid confusion, because I thought the photo in the discussion was what you were referring to..

That web page link above explains how to create a new discussion.