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Burned transistor on CC Analog board
Posted by: TjLaZer on 2018-04-24 23:13:13
I have a burned transistor on my CC Analog Board!  It happened after using a Logic board that was recapped.  The system booted up with no sound and I started to smell something burning.  The smell got stronger and stronger and I turned it off.  Inspected the Logic board and it looked ok.  But would still get a burning smell.  Took the Analog board apart to inspect and I see DD1 is toast.  I stupidly tried this Logic board an another CC and it started to do the same thing!  Now these two do not have any sound on the internal speaker.   

I need to replace this transistor to get these two CC's working again.  Not going to use the bad Logic board at this point until I can get it repaired.  I have another working Logic board I can use.

Anyone know what values these transistors are and where to get some?  Or how to figure out what type they are. 

Thanks!

NOTE:  Third pic is after I cleaned it, and last pic is another one I found, no numbers on it.

burnt transistor before clean.jpg

burnt transistor before clean large.jpg

burnt transistor.jpg

transistor different one.jpg
Posted by: trag on 2018-04-25 09:52:56
Usually, there's a little two or three character code on the transistor which might be used to identify it.  I looks like it might be worn or melted off of the transistor in the image, but that could just be the image.  Take some magnification to it and see if you can make  out numbers and letters.  If you can't, perhaps someone else with the same board can.

http://matthieu.benoit.free.fr/cross/competitive/philips/SMD-PHILIPS.pdf
Posted by: Bolle on 2018-04-25 13:11:12
Pretty sure that’s a diode and not a transistor 😉

See how the same trace is connected to the two pins at the bottom? Totally wouldn’t make sense at all if it was a transistor.
Posted by: TjLaZer on 2018-04-25 16:54:48
Why would there be 3 solder points though?  There are multiple of these types on the board.  But they are not all the same value chip.
Posted by: TjLaZer on 2018-04-26 09:03:32
Found it, it is a Diode.  M5C  Orderd from Mouser!
Posted by: trag on 2018-04-26 10:14:36
Why would there be 3 solder points though?  There are multiple of these types on the board.  But they are not all the same value chip.
Because the SC70 and SOT23 packages are standard packages into which anything (with three or fewer terminals) can be packaged.   Why they don't put them in a rectangular package like a surface mount tantalum cap, I don' t know.     May be as simple as semiconductor manufacturers are comfortable with/ have tooling for certain package types, so they shove the diodes in them too.
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