Name that SMD...

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Hi All,

My kids were watching their portable DVD player last night when, all of a
sudden, the smoke escaped :-)

Opening it up revealed a 'fried' SMD near where the 12V DC input enters the
circuit board (the 'fried' SMD is near the centre of the following photo and
the 12V DC input socket is at the top middle of the photo):
http://users.tpg.com.au/usul//DVDBoardAll.JPG

A close up of the 'fried' SMD is in this photo:
http://users.tpg.com.au/usul//DVDBoardZoom.JPG

So, anybody like to take a stab at identifying it (my guess was some form of
voltage regulator?). Yep, I probably will end up trashing it and buying a
new DVD player, but thought I'd try my hand at a repair out of interest
(I've really nothing to loose).

Thanks for your help.



Re: Name that SMD...
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photo):http://users.tpg.com.au/usul//DVDBoardAll.JPG
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photo:http://users.tpg.com.au/usul//DVDBoardZoom.JPG
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Yeah, possibly a small adjustable or pin strapable linear reg to power
some small supplementary circuit.
These things usually don't just go KAPUT on their own, probably
something else went KAPUT and took the poor fella out.
Can't help with the ID though, sorry.

Dave.

Re: Name that SMD...

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Thanks Dave,
Yes, strange it seems to have died by itself (but I see no other
damage/scorching of any other component on either side of the board - though
that's no indicator that some other component might have failed less
catastrophically), I wonder if it might have been some power surge/spike
viathe external transformer.
Thanks again.



Re: Name that SMD...
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The external supply would be a switchmode? In which case such a surge
would have likely taken out the plugpack first before it was passed on
to the 12V output.
But who knows with those cheap'n'cheerful asian plugpacks, some of
them are such a worry they almost keep me awake at night.

Dave.

Re: Name that SMD...

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wowzers look where pin 3 ended up.
remove it and see if there is any writing on the under side of the chip.


Re: Name that SMD...
finger to keyboard and composed:

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It may help if you could at least identify the supply pins. Otherwise
I'm guessing that it could be a power supply supervisor with a reset
output, although I would think that these chips would be monitoring
the 5V or 3.3V rails, not the +12V.

BTW, is it possible that the wrong DC adapter was used?

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

Re: Name that SMD...

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Thanks Franc,
It was using the same DC adapter that's been is use the past 18 month. I'll
see what further info I can discover when I remove the component from the
board (as MisterE suggested).



Re: Name that SMD...
Hi,
before you remove it - try putting a little isoporpyl on it, it may enhance
the case markings which could help, it may not - but worth a try as it will
probably fall apart when you try and remove it

Greg



Re: Name that SMD...

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http://groups.google.com/group/sci.electronics.repair/msg/3fd0514ee3c482d9?dmode=source
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Sounds amazing, I'll give it a go.
Thanks.



Re: Name that SMD...
On Thu, 02 Oct 2008 06:05:04 +1000, Franc Zabkar

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I've just checked my ADSL modem. It has two supervisor ICs, one to
monitor the CPU Vcc, the other to monitor the unregulated +12V rail
via a potential divider.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

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