I am seeing that the ICs are faulty on these boards (3407F). But how to test them? These boards are found in Samsung 50' plasma TV sets.
Testing a Buffer Board LJ41-05121A
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Re: Testing a Buffer Board LJ41-05121A
Full-time computer repair tech (10am - 6pm) and full-time, (8am - 11pm), Ruby on Rails DeveloperComment
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Re: Testing a Buffer Board LJ41-05121A
Hi there, Got the buffer boards and Y-MAIN board from Samsung 50" HD
LJ41-05120A
R1.3
Buffers LJ-05121A & 22A with R1.0
Fluke 115 set to diode RED to input between 1-24 and BLACK along OP's with no continuous bleep? at least one obvious totally blown IC U5401 on board 121A and obvious damage to Y-MAIN with blown caps, one cap so bad i could not ID it but board REF is C5817 if anyone can ID it. next obvious is C5807.
Im no pro, started trying to ment a small 22" for my daughter, friend mentioned his went off with a bit of smoke and a quote to repair, offered to help as best i could.. but really want to make sure i can replace all faults before purchasing any components etc. hope all pictures help.Comment
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Re: Testing a Buffer Board LJ41-05121A
Buffers will require lots of practice to remove and replace without damaging the board. Also a hot air station will likely be required. I am not familiar with the common mode for failure of this ysus, but a repair kit lists Q5500, Q5501, Q5302, Q5303, Q5304, Q5306, as well as 2 surface mount resistors, 3 capacitors, 1 zener diode, buffer chip is IC 3407F. However that cap that is blown to pieces is not one of the common ones to fail so your board is likely in worse shape than the normal failureLiberating magic smoke one part at a timeComment
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Re: Testing a Buffer Board LJ41-05121A
Hi there, Got the buffer boards and Y-MAIN board from Samsung 50" HD
LJ41-05120A
R1.3
Buffers LJ-05121A & 22A with R1.0
Fluke 115 set to diode RED to input between 1-24 and BLACK along OP's with no continuous bleep? at least one obvious totally blown IC U5401 on board 121A and obvious damage to Y-MAIN with blown caps, one cap so bad i could not ID it but board REF is C5817 if anyone can ID it. next obvious is C5807.
Im no pro, started trying to ment a small 22" for my daughter, friend mentioned his went off with a bit of smoke and a quote to repair, offered to help as best i could.. but really want to make sure i can replace all faults before purchasing any components etc. hope all pictures help.Comment
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Re: Testing a Buffer Board LJ41-05121A
thanks, i had thought the same in relation to the damage, as it's not the common failure.
paulComment
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Re: Testing a Buffer Board LJ41-05121A
Yeah, pretty nasty isn't it, this was my first thought when i seen the buffer IC that it has probably burned through the tracks on the board.. very unfortunate has been quite a failure to cause that damage to the boards, so put it down to a write off lol.
thanksComment
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