DVD PS - help identifying damaged components

[centaur068]

Here's the scoop.. PS came out of a DVD Player, heard a pop during a t-storm and of course it doesn't work any more (big surprise).

Decided I would give it a shot to see if I could repair it (it's a dvd player, nothing critical here). I'm well aware the problems could be numerous in a situation like this, but i'm going to take a crack at it anyways.. with that said..

I've inspected this thing closely about a dozen times and located two places of physical damage, one was a red LED, the other some surface mount device.. See pictures attached

I understand basic electricity (from a physics point of view) and can replace caps just fine (ive got a pretty steady and precise hand), Here are the q's:

1) When replacing the red LED, what technical specs should I be concerned about to get an exact or close to exact match? Can I find a replaceable match? See pictures attached

2) What is that surface mount device where the casing is blown off? (Pardon my electronics noobness) Is this a diode, a transistor, something else entirely? Seems like some sort of switching device. See pictures attached

3) Same questions as #1 but for the surface mount device. What things should I be concerned with when looking for a replaceable part?

4) Anything in particular I could quickly check with a DMM to help discover other damaged parts?

Thanks in advance for any help,
- centaur068

[shadow]

Re: DVD PS - help identifying damaged components

I do not think that the exact specifications for the LED are important. However get one that is similar in size and it will probably have similar or maybe the same specs as old one (that is only a guess thou).

The burnt SMD component is a small transistor. It is difficult to tell what sort it is because it is half blown off (so you can not see the model at all).

Maybe someone else can help you out more.


Assuming that only the power supply is stuffed, you could probably fix this without too many problems. It is a relatively simple design. I guess this could be good and bad.

Maybe if you knew what voltages are required from the power supply you could use an ATX power supply or another small power supply just to make sure that the other parts of the DVD player are working correctly.

[Krankshaft]

Re: DVD PS - help identifying damaged components

Check the line rectifier diodes (to the right of the big cap), the main switching transistor (on the tiny heatsink), the secondary diodes (the diodes from the power switch all the way back to the transformer), and any large resistors. Any of these parts may have been blown up by the strike.

As for your transistor look at the circuit it's in and what polarities you are dealing with. In order to determine it was an NPN or PNP. A general purpose transistor will probably suffice.

From the pics you gave the transistor is probably a latch for the on / off switch.

[i4004]

Re: DVD PS - help identifying damaged components

you have burnt components on the secondary(output) of the smps, so what is suggesting remainder of the dvd(esp. the video chips) survived this accident?
it probably didn't.

and looking at the voltages it gives, it's non-trivial to find something to replace it with just to check if rest is ok....and then see if fixing smps will bring it back to life at all...

again, tough....