Panasonic sc tnpa5081 rebuild

[tongshadow]

Re: Panasonic sc tnpa5081 rebuild

Been running the set for 16 hours so I guess it's safe to say it's been fixed, model is P50V20B. Will definitely post again if something bad happens.

I used TNPA 5105 parts, mostly identical components but had to substitute some of them.

Q421/Q422 - DG402RP replaced by RJP43F4A
Q621/Q622 - 30F125 replaced by higher spec 30J127 and 30F124. These are from Samsung YSUS Boards, the TNPA 5105 comes with a single RJP3034, which is probably fine but I wanted to go higher spec.
Q661 - RJP63F3A replaced by RJP63F4A.
D451 - RNF25 replaced by RFUS 20.

I would recommend using a TNPA 5175 Board as a source for parts, it has identical components to the TNPA 5081 but has even more IGBTs, and like I said avoid chinese or part kits at all costs, 90% chance of them being fake.

Also found this incredibly useful 200+ page document for repairing SC/SN boards from models ranging from 2010~2012:
https://www.scribd.com/document/4485...ing-Manual-pdf

Here to report the TV is still going on strong!

[tongshadow]

Re: Panasonic sc tnpa5081 rebuild

Been running the set for 16 hours so I guess it's safe to say it's been fixed, model is P50V20B. Will definitely post again if something bad happens.

I used TNPA 5105 parts, mostly identical components but had to substitute some of them.

Q421/Q422 - DG402RP replaced by RJP43F4A
Q621/Q622 - 30F125 replaced by higher spec 30J127 and 30F124. These are from Samsung YSUS Boards, the TNPA 5105 comes with a single RJP3034, which is probably fine but I wanted to go higher spec.
Q661 - RJP63F3A replaced by RJP63F4A.
D451 - RNF25 replaced by RFUS 20.

I would recommend using a TNPA 5175 Board as a source for parts, it has identical components to the TNPA 5081 but has even more IGBTs, and like I said avoid chinese or part kits at all costs, 90% chance of them being fake.

Also found this incredibly useful 200+ page document for repairing SC/SN boards from models ranging from 2010~2012:
https://www.scribd.com/document/4485...ing-Manual-pdf

[tongshadow]

Re: Panasonic sc tnpa5081 rebuild

Update. List of bad parts based off the SC Board repair kit.



Red checkmark = Bad, needs to be replace
Blue X = Good
?? = Unable to determine, will compare to a good board

I couldnt find a spare TNPA5081 board, so I ordered a TNPA5105 board because it has enough identical components, except for DG402RP, I'll need to find a proper replacement for that.
And no, I didnt order parts from China or so-called "new parts" because they're a 100% fake. Plasmas havent been in production for nearly a decade and it doesnt make sense for new specific components to remain in production. I learned the hard way trying to repair a Samsung Plasma set, fake parts destroy parts that would never fail in a million years. I ONLY TRUST IN PULLS FROM ORIGINAL BOARDS.

[tongshadow]

Re: Panasonic sc tnpa5081 rebuild

Hi, long time lurker, first time poster. Good to see someone logged the maintenance process for this board, very hard to find solid info.
I recently got one of these Panasonic Plasmas that use the same board, 4 blinks error. The power supply has shots and so does the SS board. The SC board? Well, take a look at it...


Yea, something REALLY bad happened, I've never seen a FET go out like this.
I couldnt find a new SC board for sale, so I'll try my hand at repairing it. These sets are worth saving because it's a 1080p Plasma that apparently use the same technology as the legendary Pioneer Kuros, arguably the best Plasmas ever made and possibly the best TV.

[autoperformance]

Re: Panasonic sc tnpa5081 rebuild

Woo Hoo! Just fixed my first TNPA5081

I had a few snags. first attempt failed as I did not detect 2 shorted smd transistors which fed the inverter chip. Result of that was flash of light, and pop. The only casualties were the inverter chip I replaced and the 3.9k 1/8w resistor.

2nd problem is these Toshiba IGBTs which have 2 variations and I'm getting no feedback from the post.

I'm in 2 minds, sub the replacements in the board and see if it works or leave it alone given the amount of hours I've put in.

This is the list of parts replaced.

IC16501 M81737FP FET driver
IC16521 M81737FP (only one failed but replaced both)

Q16402 DG502LW shorted
Q16403 DG502LW shorted

Q16421 DG402RP shorted
Q16422 DG402RP shorted

Q16661 RJP63F3A shorted

IC16773 TC7SH14F, Toshiba , Schmitt inverter ,marking HA
Q16701 MMBTA92 NXP (7E W) shorted
Q16702 2PD601ART NXP (C3 W) shorted , these I cannibalised from the first board as they cost stuff all but have to order large quantities and I was so close to fixing it I could'nt wait to get one going.

Q16021 30F125 ®
Q16022 30F125 ® only one had shorted on each board. Have not located this version transistor so one board has become a donor for these

Q16441 Q16452 45G128 ® & 45G128 ended up fine.

On the first board, IC16724 5V 78M05 is shorted, the 5V line on the matching buffers was also short.

Not on this fixed board it was fine, so to the other is fine.

I hope someone out there can help me out with the IGBTs.

Even if somone can get them B1JADN000008 from Panasonic parts stockists cheap and ship to me

Where are you get your part at a good price ?
I only find part in a repair kit with no description what part inside 🙄
Thank you for your help and your interresting thread.

[Unspun01]

Re: Panasonic sc tnpa5081 rebuild

I was hoping that the 81707 and 81737 were somewhat interchangeable...

The 81707 is called a "HIGH VOLTAGE HALF BRIDGE DRIVER"
The 81737 is called a "DUAL HIGH SIDE DRIVER"

Otherwise the schematics and pinouts are largely identical (except the output current as you indicated)

There is a discrepancy between datasheets in ROW 4 of the datasheet function table for both ICs. specifically on 81707 I think LO=HO = Low should be LO=HO= High because it doesn't match itself. Not sure what that crap means anyway.

I did substitute the 81737 for a 81707 on a TNPA4782 but my repair was not successful.

I dnn't know if I should blame my substitution, or if there was some other reason the repair failed. Perhaps I missed some other small component or something I should have replaced and didn't...

These board are a real pain to fix because if you miss one component, you can almost be sure the board will fry all over again.

[Darthzorg]

Re: Panasonic sc tnpa5081 rebuild

Hello there,
I'm no expert but from the datasheet the only "big" difference i see is on the output current, where the 81737 can drive up to 225mA while the 81707 is limited to 100mA, i'm pretty confident you can use a 737 in place of a 707, doing the opposite will require some study of the circuit, probably will work but might end frying your chip sooner ?

[Unspun01]

Re: Panasonic sc tnpa5081 rebuild

I'm wondering, what's a good way to test these ICs (M81737FP) to make sure they're good or not ?

I also have this question about testing M81737FP (for boards like TNPA5081) and M81707FP (for boards like TNPA4782)

Both ICs are SOP-16 package, and datasheets appear to be very similar (see attached).

I'm trying to repair a TNPA4782 SC board and I have a few TNPA5081 parts boards that I would like to scavenge parts from... This may also help someone doing the reverse...

Can the 81737 (on TNPA5081) be substituted for 81707 (on TNPA4782) or vice versa?

Any Panasonic experts have some insight on this?

[Darthzorg]

Hello,
Recently my good old Plasma TV failed (it's a TX-P50VT20E) with a 10 blink code, after some digging and testing i realized that the problem was on the SC board and this is when I found this fabulous forum.

So after reading some posts i tested a few components and here some finds (btw the board is the AY version):
Q421 (DG402) BAD
Q422 (DG402) BAD
Q402 (DG502) BAD
Q403 (DG502) BAD
Q661 (RJP63F3A) BAD
Q621 (30F125) OK
Q622 (30F125) OK
IC773 (TC7SH14F) BAD
IC771 (78L05L) OK
D702 OK
Q701 OK
Q702 (2PD601ART) BAD
Q452 (GT45G128) OK

Surprisingly both 30F125 seems to be ok (i removed them from the circuit and measured resistence, i forgot to write these down but i'm sure they were above 20K, so i assume they are good)
Then I did measure resistence of the following :
- Vout-Vad (pin 1 and 2 of IC771) and i get 5.83 KOhm (seems ok)
- across C561 and I'm getting 5.58 K (should be ok)
- TP82-GND, i get resulsts only in continuity/diode mode, with positive on GND and negative on TP82, read 970
- Q521 measured i get out of scale results (my meter only goes up to 2 M, so guess is ok)
- Q552 i get 250 Ohm, removed but out of circuit it measures same as Q521

as i'm sure i Q452 was ok (i removed from circuit when testing) i tested again IC521 (M81737FP) and i only get 250Ohm from pin 6 and 7, while on the other M81737FP (IC501) i get a much higher result (tested in circuit) so i belive IC521 is also bad.

I'm wondering, what's a good way to test these ICs (M81737FP) to make sure they're good or not ? Also, on IC 771 when measuring resistence between Pin 2 (vad) and pin 3 (16V_F) i get a "growing" value that stops at about 1.7K which still seems a bit low (at least cheking the schematics) so i've been testing all the 16V_F line but couldn't find anything wrong at first sight, any suggestion or is the 1.7K value correct ?
Also, any suggestion on some other things i should be checking ?

[ultimatemj]

Re: Panasonic sc tnpa5081 rebuild

Replaced the SC board, and the SS board...TV is working again!

But the black is not black, there is "snow". Does that indicate another failure, or did I need get all the ribbon cables properly reconnected?

Should I post this question in a different thread?

[ultimatemj]

Re: Panasonic sc tnpa5081 rebuild

Hi, I've diagnosed a shorted SC board, but I'm struggling to identify which TNPA5081 I have. Meaning, AH, AK, AY, etc? Does it matter?

My board doesn't have anything in the yellow square, where I notice other boards do.

[11alon11@gmail.com]

Re: Panasonic sc tnpa5081 rebuild

I am in Toronto Canada

[11alon11@gmail.com]

Re: Panasonic sc tnpa5081 rebuild

I have 2 Panasonic sc tnpa5081af working $100.00 each

[t-echnics]

Re: Panasonic sc tnpa5081 rebuild

You'll work it out.

While I am waiting to get a used board, I desoldered some of the shorted parts.
Actually, now I am wondering, where I could get those parts (without paying too much).
Do you have any recommendations?
I could get the parts really cheap from chinese suppliers, but I really doubt the quality of the parts (maybe they are fake...).

[AnthonyC]

Re: Panasonic sc tnpa5081 rebuild

Big thanks to all that contributed to these Panny SC board threads. I have this problem and just diagnosed a bad SC board based on the troubleshooting guide someone posted here.

Right now I'm deciding if I have a rebuild in me or just pay for a refurb, but this thread has been a great source of info. Thanks.

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

Thank you, but I also found this blog-entry: http://alpengeist-tvrepair.blogspot....massively.html

He obviously managed to turn an AY into an AH and the boards really look quite the same, also in that left area (as far as I can see in this pictures...)

Well, firstly he's wrong. they are not the only differences. It may well very be that going backward from 3D to 2d you get away with that but you won't going the other way unless of course that part only activates under 3D.

I personally don't know.

The SD boards also are different.

Images are too poor to judge but the ones on on Shopjimmy are not and you will spot the differences or copy the entire parts list from each models SC board into a column of excel and compare what parts are there and what are not.

You'll work it out.

[t-echnics]

Re: Panasonic sc tnpa5081 rebuild

You only have the two options I gave or will be a genius effort to reconstruct the AH to be AY because the circuitry in entirely different in that left hand congested area where the SC20 ribbon is.

Thank you, but I also found this blog-entry: http://alpengeist-tvrepair.blogspot....massively.html

He obviously managed to turn an AY into an AH and the boards really look quite the same, also in that left area (as far as I can see in this pictures...)

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

Sorry to bother you again.
Could I also use a AH board, if I replace the big caps and coils which are obviously different or are there any other differences?

You only have the two options I gave or will be a genius effort to reconstruct the AH to be AY because the circuitry in entirely different in that left hand congested area where the SC20 ribbon is.

[t-echnics]

This board will work AK and AY both fitted to the 50"3D models

Sorry to bother you again.
Could I also use a AH board, if I replace the big caps and coils which are obviously different or are there any other differences?

[t-echnics]

My wife often wonders why I buy broken bits when nothing is broken.

Same as mine ;-)
Actually I got this TV with this failure for free - I already own two smaller Plasmas from Panasonic and really like their colors.
So I can wait to get some spare parts, but it's really a shame I did not get the other smashed one...

Thanks for your help!