Samsung SyncMaster 913BM

[daroo]

I've just repaired 3 monitor like this but the fourth is giving me some problems.
I've tested it with good components frome the other monitor and found out this is the board with the problem.

Is there something I can check or it must be replaced?

[daroo]

Re: Samsung SyncMaster 913BM

The green led stays on but the display doesn't turn on. Iv'tried with another board (taken from another syncmaster) and the display works perfectly. So the problem is that board!

[selldoor]

Re: Samsung SyncMaster 913BM

Pictures are poor second one is useless and you dont say which board you have replaced?

[daroo]

Re: Samsung SyncMaster 913BM

Sorry for bad photos, I've taken 3 other pics.


I've tried replacing the green board (the one with dvi and vga connection) with one from a working syncmaster and it works. so the problem is on that green board.
The problem is that I can't find any visible broken component on that so I asked for your help.

[selldoor]

Re: Samsung SyncMaster 913BM

Doesnt look stessed but perhaps test the regulator top right 7806abd2t
should output 6v. Also check R502 nearby and R503 near the TDA Chip
0 rated so just for continuity.

[daroo]

Re: Samsung SyncMaster 913BM

Doesnt look stessed but perhaps test the regulator top right 7806abd2t
should output 6v. Also check near the TDA Chip
0 rated so just for continuity.

I've tested and the regulator gives 0 volts. Iv'e tried on a working 913bm to be sure it wasn't my fault and it gives 6v as you said.
R502 and R503 give continuity as they should.

[daroo]

Re: Samsung SyncMaster 913BM

The working board gives 13v input and 6v in output (only with a dvi or vga connected). the faulty one gives 0v and 0v.

[selldoor]

Re: Samsung SyncMaster 913BM

Perhaps need to test the associated cap C500 to see if it is shorted.

[daroo]

Re: Samsung SyncMaster 913BM

Perhaps need to test the associated cap C500 to see if it is shorted.

Thank you for your help
I've just checked continuity and it's not shorted
Is there anything else I can check?

[daroo]

Re: Samsung SyncMaster 913BM

I've found that C607 is shorted!

[daroo]

Re: Samsung SyncMaster 913BM

the problem is the APL5522 (IC601) which is faulty

[selldoor]

Re: Samsung SyncMaster 913BM

Well found !! can you find one or its equivalent to buy

[daroo]

Re: Samsung SyncMaster 913BM

I'll try to go to a local Tv repairer. How can I find the code of an equivalent?

[selldoor]

Re: Samsung SyncMaster 913BM

I cant find an equivalent - I have looked a quite a lot of datasheets but cant see any for outputs of 3.3 and 2.5v at 500ma. What is odd there are so many places with datasheets but no-one seems to sell them. perhaps this from russia!!!
http://radiohobby.info/catalog-pdc402335.html if you use google translate it should
translate the whole webpage into italian.


Perhaps start a new thread in general elecronics headed "Dual regulator APL5522 or EQUIVALENT" and ask if anyone knows.

Maybe we should be looking for a cheap board instead?

[budm]

Re: Samsung SyncMaster 913BM

So NO output from pin 1, or pin 4? Input Voltage pin 2-3 is?
Output resistance of pin 1, pin 4 are?
BTW, what is the P/N of the IC600?

[R_J]

Re: Samsung SyncMaster 913BM

I think Utsource carries them, I have ordered from them before. The +5 volts in goes through D600 (s1g) to pins 2-3 of ic601
Budm, Looks like ic600 is a FDS9933 According to the diagram

[selldoor]

Re: Samsung SyncMaster 913BM

Budm, Looks like ic600 is a FDS9933 According to the diagram

What diagram? I can make out 933A in one of the pictures

[budm]

Re: Samsung SyncMaster 913BM

I think Utsource carries them, I have ordered from them before. The +5 volts in goes through D600 (s1g) to pins 2-3 of ic601
Budm, Looks like ic600 is a FDS9933 According to the diagram

Yes, I traced that line, it is fed through that diode but not sure if 5V is fed through that switch MOSFET IC600 first or not, it looks like the IC600 is the switch for supplying the VCC to the LCD panel.

[R_J]

Re: Samsung SyncMaster 913BM

This one is for the 913N but looks very close.