Samsung UN50NU6900FXZA

[Eddie3]

Re: Samsung UN50NU6900FXZA

The bridge rectifier is a common target of mains spikes, it's today's normality, many and many faults due to high power devices turning in operation, such as air conditioners, this is my bet, needed power surge suppressors in the "electric lever box"', sorry don't remember real name, have you done what i have said? so dismounting first the bridge? i don't read this..

The main box is connected to a panel of several circuit breakers and TV is usually connected to the 15A breaker. But I think you're absolutely right about using a surge protector/suppressor on the TV.

No, not yet on the bridge (8 solder points) because I'm still haven't finished getting out the MOSFET (6 solder points). It's been difficult because circuit board is double-sided.

I bet you guys (who work on these TVs eryday) use those Electronic Desoldering Vacuum pump device for component removals.

Thanks

[tsyaada]

Re: Samsung UN50NU6900FXZA

Hello

I think this power mosfet as per your attached and If you want to figure out what the value of this mosfet for replacing it, you have to remove first the mosfit then turn the main borad ON after that try to measure three joints of the mosfet directly on the board which is VD, VG, and VS for those values you can predict the new device to be replaced.


Good Luck

[Eddie3]

Re: Samsung UN50NU6900FXZA

Hello

I think this power mosfet as per your attached and If you want to figure out what the value of this mosfet for replacing it, you have to remove first the mosfit then turn the main borad ON after that try to measure three joints of the mosfet directly on the board which is VD, VG, and VS for those values you can predict the new device to be replaced.


Good Luck

Appreciate your suggestions. I really wish I had a schematic diagram, so that I could read directly from it as to what the part number of that MOSFET actually is. But I am hopeful that it didn't burn off the labeling, unless Samsung is using an unlabeled, proprietary MOSFETs in their TVs.

[Davi.p]

Re: Samsung UN50NU6900FXZA

I don't find the way of let you understand me.. i said that removing the mosfet for first is probably a waste of time and probably a further damage, with many substrate boards is difficult removing, try to remove first the bridge, the mosfet is probably ok. Am i clear? i have a further advice, cut the + leg of the diode bridge and measure again the mosfet.. if ok, then cut the remaining legs, leaving enough lengh to solder to them the new bridge...

[Eddie3]

Re: Samsung UN50NU6900FXZA

I don't find the way of let you understand me.. i said that removing the mosfet for first is probably a waste of time and probably a further damage, with many substrate boards is difficult removing, try to remove first the bridge, the mosfet is probably ok. Am i clear? i have a further advice, cut the + leg of the diode bridge and measure again the mosfet.. if ok, then cut the remaining legs, leaving enough lengh to solder to them the new bridge...

I apologize for not responding sooner; and thank you for suggesting to check the bridge rectifier firstly, by cutting leg(s).

However, the problem was finally resolved when I bought a used compatible board:
BN96-48456A.

I was pleasantly surprised when the backlight came on and the setup started by the TV talking to me. Ha!

I then slapped the back panel back, attached stands, updated the firmware and tested for functionality. Everything works.

Thank you all very much for your advice and I hope my experience will help others with a similar issue.

[Davi.p]

Re: Samsung UN50NU6900FXZA

board changements at early stages is very boring to me, nothing new to learn.. sadly..