Samsung LCD TV 32 inch Model No LA32E420E2RMXL please help Identify burnt fets

[muanpuia]

I have Samsung LCD TV 32 inch Model No LA32E420E2RMXL. It suddenly died yesterday. As you can see in the pictures, the backlight inverter use SEM2106 IC and i cant find the datasheet for it. The inverter balancer board is confusing for me. In every CFL connection ive seen, theres always two wires. But theres only single contact each in six position in a slot contact type connector as you can see from the picture. In the last picture, i have drawn red rectangle to show that these two mosfet were burnt, and i cant see the markings. Also it seems to switch the high voltage instead of low voltage (12-15v) in most inverter circuit. Can anybody help me with this TV please?

[mscserbia]

Re: Samsung LCD TV 32 inch Model No LA32E420E2RMXL please help Identify burnt fets

IT could be IRS2106 ic

[mscserbia]

Re: Samsung LCD TV 32 inch Model No LA32E420E2RMXL please help Identify burnt fets

here is datasheet

[tom66]

Re: Samsung LCD TV 32 inch Model No LA32E420E2RMXL please help Identify burnt fets

This inverter probably uses U-shape CCFL so each pair of contacts is one U-shape CCFL.

[selldoor]

Re: Samsung LCD TV 32 inch Model No LA32E420E2RMXL please help Identify burnt fets

IT could be IRS2106 ic

I dont think so - hasnt got enough legs? 14 v 24 ?

Main problem seems to have got lost - he has 2 burnt out fets that he said were marked out - but they were not - I have redone the picture.

Part of the problem is that it is a board made for the Indian Market so not many pictures of them anywhere.

I suspect the fets are a standard sort of component if anyone can suggest some that might work.

Muanpuia- did you try cleaning them with IPA - also can you measure them
- that might help finding some that might fit - hehe I have seem some
repairs where instead of surface fitting they had fets on legs - looked weird but worked
The IC might be similar to the SEM2006

[muanpuia]

Re: Samsung LCD TV 32 inch Model No LA32E420E2RMXL please help Identify burnt fets

Thank you all. Now the IC is SEM2106 and looks compatible to SEM2006 like selldoor said. The 2 Mosfet, cleaned it with IPA now and its SN52U from STmicro. I cant find the replacement locally, so i wired up the once popular MJE13007 from common CFL bulb driver. To prevent further destruction, with a serial bulb i turn it on hoping to see the 13007 bursting hehe. But the Mosfet is not switching at all, i tested the small transformer that drives it and its OK. The main power LED blinks at about every 5 secs. I checked the ps-on signal at the other connector in this IP Board while trying all these. It randomly turns on/off at every time (about 5sec) it blinks. I really means random, sometimes it goes to 3.3v for consecutive 4 blinks then turns off at the next blink, its so weird now. And the power LED doesnt even hold the light while the ps-on signal is there, it just blinks every interval. And yes tom66, the CFL is U shaped, it uses 3 of em.

[selldoor]

Re: Samsung LCD TV 32 inch Model No LA32E420E2RMXL please help Identify burnt fets

Hi cant find a data sheet for SN52U have you got one or is it one of these
http://nl.farnell.com/stmicroelectro...pak/dp/2098183

[tw2005]

Re: Samsung LCD TV 32 inch Model No LA32E420E2RMXL please help Identify burnt fets

Think you'll find the marking has been misread. 5N52U makes more sense and comes up easy in a search as DPAK or TO-220FP. I think the full number for DPAK will be STD5N52U ST Micro. 525V 4.4A N channel

https://cdn.badcaps-static.com/pdfs/...d80b1173ee.pdf

[selldoor]

Re: Samsung LCD TV 32 inch Model No LA32E420E2RMXL please help Identify burnt fets

Thanks tw2005 I think the transistor he has tried is a totally different animal - have you experience of these? doesnt even describe it as being a mosfet?
https://cdn.badcaps-static.com/pdfs/...4bf6f39714.pdf

[muanpuia]

Re: Samsung LCD TV 32 inch Model No LA32E420E2RMXL please help Identify burnt fets

Yeah 13007 is an NPN transistor, i got lots of them from old fluoro lamp pcb. Cant find the right mosfet, im frustrated so i just try 13007. Anyway, im thinking the mainboard should turn on anyway with no backlight, but it doesnt as ive posted earlier. Because if it can work without backlight, ill just put a 2ft fluoro behind the screen like i have done in other system. Im using bike spark plug ignition coil and it used to work like a charm, can even adjust brightness in a very wide range.