Panasonic sc tnpa5081 rebuild

[Alastair E]

Re: Panasonic sc tnpa5081 rebuild

Yes that is correct and I am testing them out of Circuit.

If you can test a Q661 / RJP64F4A out of circuit I have a felling I have some bad parts just not sure which ones.

The RJP64F4A I received from utsouce and they look bad.

I order some more off of eBay from a guy in the states and they look much better?

Ive had some from UT, and Generally been fine. Ive used one--in my washing-machine as the switching IGBT supplying the Motor!

I was not so lucky when I changed a perfectly good RJP63F3A for one of the UT sourced RJP63F4A in a 5081, --which is summit I do when I find working SC boards in sets for reliability--I have a theory that its the Q661 fails--and kills everything else....

Killed it! Bugger! All the usual parts are short, the DG502, DG402 et-al as well as Q701,2 probably IC773 and its friends.....
Shoulda left well alone, now Ive got yet another SC to rebuild....

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

Ive had some from UT, and Generally been fine. Ive used one--in my washing-machine as the switching IGBT supplying the Motor!

I was not so lucky when I changed a perfectly good RJP63F3A for one of the UT sourced RJP63F4A in a 5081, --which is summit I do when I find working SC boards in sets for reliability--I have a theory that its the Q661 fails--and kills everything else....

Killed it! Bugger! All the usual parts are short, the DG502, DG402 et-al as well as Q701,2 probably IC773 and its friends.....
Shoulda left well alone, now Ive got yet another SC to rebuild....

It does run bloody hot. I wonder if another was paired up to share the load?

[Alastair E]

Re: Panasonic sc tnpa5081 rebuild

Maybe--I think its adequately rated, just the heatsink is too small--Does seem to have gone through a few revisions too, from RJP63F3, to RJP63F3A to RJP63F4 and the latest Ive seen is RJP63F4A...
--Dunno what Thats all about, but suspect various measures to increase (Un) reliability....

Q661--Appears to be the set/reset ramp generator part of the circuit as far as I can gather, and would be expected to get pretty warm due to the dissipation I'm assuming goes on there....

Only on one or two of the smaller SC boards does it have a long heatsink--like those found in 37S2/X20 type sets, those don't seem to run excessively hot, but still pretty damned warm....

[dolivas27]

Re: Panasonic sc tnpa5081 rebuild

I've never tried it. i have on a LG 2010 FHD tried it because the panel was smashed and got away with it. But i disconnected everything from the panel , both sustains and the bottom drive boards (c boards)

I can't advise.

If the panel was bad then I'd expect the buffer to blow and the SC.

Long shot but is the ic724, 5v for the sd/su. check that is ok. pin 3 - Vfg 2.6k ohms. near that sc50 connector.

I'd expect it to be ok , only once I'have it bad but tyhe buffers were bad too with the 5V line shorted on the buffer boards

ic724 reads right 2.6k.

[dolivas27]

Re: Panasonic sc tnpa5081 rebuild

Check all the gate resistors are good on the IGBTs.

This could be a BS thought but the 30F125, DG402 & DG502 are all in banks in parallel. I'm wondering if any resistors are open that transistor would not be running and with the load maybe too much on what is? They can burn out but not always obvious visually.

think there's 10ohm, 5.6ohm 7.5ohm

All these test ok.

Here's a picture of the RJP63F4A that I have received.

I am also wondering if I might have made a bad parts substitution?

I used this part for D461 & D462

Original Part # RF2001TM3SW ( Do you have any information on this part?)

Part # I am using RF2001T3D (FAST 300V 20A)

The plan right now it to test every component on the board I will be removing all transistor to test out of circuit. Maybe there is another leaky transistor like I found on Q608.

Anyways keep the feed back coming it helps just in case I missed something.

The thing that has me going nuts is when I get it repaired and it works with out the buffer boards? Once a load is applied POP she goes....

Any parts you think I should just replace? At this point I think I have them all....

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

off the top of my head, RF2001TM3SW should be a 300 -330V , 20A single diode. The T3D would be a double diode. Not sure if that would affect anything. If you have a RFN25TM4SW or FN.......... that would do. i've experimented with different diodes even lower voltage from 400 down to 300V but same or higher amp and had no issue . Only done that once cause I was short and wanted to prove the baord, then replaced it with the higher voltage.

Will be either ROHM or RENESAS product those diodes

[dolivas27]

Re: Panasonic sc tnpa5081 rebuild

off the top of my head, RF2001TM3SW should be a 300 -330V , 20A single diode. The T3D would be a double diode. Not sure if that would affect anything. If you have a RFN25TM4SW or FN.......... that would do. i've experimented with different diodes even lower voltage from 400 down to 300V but same or higher amp and had no issue . Only done that once cause I was short and wanted to prove the baord, then replaced it with the higher voltage.

Will be either ROHM or RENESAS product those diodes

I have some of these on hand do you think I could use them?

RFUS20TM4S

http://www.mouser.com/Search/Product...755-RFUS20TM4S

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

I have some of these on hand do you think I could use them?

RFUS20TM4S

http://www.mouser.com/Search/Product...755-RFUS20TM4S

I'd use them

[dolivas27]

Re: Panasonic sc tnpa5081 rebuild

Ok chasing my tail on this one I am not sure if I am over thinking this now but I think I might have a problem with the diodes I installed.

(Recap of what has been done so far)

So I get the board repaired and it powers up and tests fine with the SC50 jumper installed and the buffers disconnected.

Reconnect the buffers test aging for shorts everything looks good. Power the TV up and BAM loud POP and another body bag of parts blown.

Ok so thinking out loud now…..

The board powers up fine NOT under load right?

With the SC50 installed and the buffers unconnected that's just testing the voltages of the board it's really not testing the board under load right?

@ tw2005 After you pointed out my diode error I am going over everything again for the next repair attempt.

Here's what I have on my current board for parts if someone could please verify the parts that would help.

D16422, D16461, D16462, D16481, D16482 are all the same part# RFUS20T4S looking at the schematic it's a dual diode.

I replaced D16481 with a RFUS20TMT4S (This is a single diode it has the correct current but not the correct voltage) Now this diode did not blow on the last repair but I still think this is the wrong diode to use?

@tw2005 you posted this here and I think that's how I got the diodes mixed up.

Another note, D482 which was a RFN25TM4SW and I can't find, I've used a RF2001T3D which is a 100V less and a double diode. obviously it's working with it but would have preferred the same 400V rating. See how it goes I guess.

https://www.badcaps.net/forum/showpo...&postcount=104

So your saying on your board the D16482 was a RFN25TM4SW and that's a single diode? What SM where you using that showed this as a single diode?

(After going through all my parts I did in fact order some RFN25TM4SW and I have (10) of them.

D16641, D16642 are the same part# RF2001TM3SW looking at the schematic it's a single diode.

I replaced D16641 & D16642 with RF2001T3D (This is a dual diode with the correct current but not the correct voltage from what I can see)

Well that is the mess I have going on in my head and I need to know if you think having the wrong diodes in D16641 & D16642 is causing the unit to blow under load?

Let me know you thoughts and what you would use to replace the diodes listed.

I have these on hand RFN25TM4SW, RFUS20TMT4S, RF2001T3D

Thanks

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

Ok chasing my tail on this one I am not sure if I am over thinking this now but I think I might have a problem with the diodes I installed.

(Recap of what has been done so far)

So I get the board repaired and it powers up and tests fine with the SC50 jumper installed and the buffers disconnected.

Reconnect the buffers test aging for shorts everything looks good. Power the TV up and BAM loud POP and another body bag of parts blown.

Ok so thinking out loud now…..

The board powers up fine NOT under load right?

With the SC50 installed and the buffers unconnected that's just testing the voltages of the board it’s really not testing the board under load right?

@ tw2005 After you pointed out my diode error I am going over everything again for the next repair attempt.

Here’s what I have on my current board for parts if someone could please verify the parts that would help.

D16422, D16461, D16462, D16481, D16482 are all the same part# RFUS20T4S looking at the schematic it’s a dual diode.

I replaced D16481 with a RFUS20TMT4S (This is a single diode it has the correct current but not the correct voltage) Now this diode did not blow on the last repair but I still think this is the wrong diode to use?

@tw2005 you posted this here and I think that’s how I got the diodes mixed up.

Another note, D482 which was a RFN25TM4SW and I can't find, I've used a RF2001T3D which is a 100V less and a double diode. obviously it's working with it but would have preferred the same 400V rating. See how it goes I guess.

https://www.badcaps.net/forum/showpo...&postcount=104

So your saying on your board the D16482 was a RFN25TM4SW and that’s a single diode? What SM where you using that showed this as a single diode?

(After going through all my parts I did in fact order some RFN25TM4SW and I have (10) of them.

D16641, D16642 are the same part# RF2001TM3SW looking at the schematic it’s a single diode.

I replaced D16641 & D16642 with RF2001T3D (This is a dual diode with the correct current but not the correct voltage from what I can see)

Well that is the mess I have going on in my head and I need to know if you think having the wrong diodes in D16641 & D16642 is causing the unit to blow under load?

Let me know you thoughts and what you would use to replace the diodes listed.

I have these on hand RFN25TM4SW, RFUS20TMT4S, RF2001T3D

Thanks

On the original TNPA5081AP out of a 50GT25, Q422 is a RFUS20T4S and the manual show Panasonic part# B0FACP000005 and is the only location on that revision.

In the 54G20/25 manual it shows D16422,D16461, D16462, D16481, D16482 are B0FACP000005 so this should cross back to what you say.

I would not get sucked in too much with the symbols as they may not necessarily match the item exactly.

basically the S means single, D means double so they're singles.

If I said I subbed a T3D(double) 300V 20A for a 430V single and it worked then that's exactly what happened and it was run for a number of weeks.

I go by the datasheets data supplied by ROHM not the imagery in the schematic.


I would use , RFUS20TMT4S, RFN25TM4SW for RF2001TM3SW as they're all single diode but I don't think this is the issue but give it a go.

How many more goes before the tracks are stuffed you reckon?

I honestly don't know what to think here on this one and I've only done the 50" versions

[dolivas27]

Re: Panasonic sc tnpa5081 rebuild

On the original TNPA5081AP out of a 50GT25, Q422 is a RFUS20T4S and the manual show Panasonic part# B0FACP000005 and is the only location on that revision.

In the 54G20/25 manual it shows D16422,D16461, D16462, D16481, D16482 are B0FACP000005 so this should cross back to what you say.

I would not get sucked in too much with the symbols as they may not necessarily match the item exactly.

basically the S means single, D means double so they're singles.

If I said I subbed a T3D(double) 300V 20A for a 430V single and it worked then that's exactly what happened and it was run for a number of weeks.

I go by the datasheets data supplied by ROHM not the imagery in the schematic.


I would use , RFUS20TMT4S, RFN25TM4SW for RF2001TM3SW as they're all single diode but I don't think this is the issue but give it a go.

How many more goes before the tracks are stuffed you reckon?

I honestly don't know what to think here on this one and I've only done the 50" versions

I should be good for a few more on the tracks. I have hot air and a JBC Desoldering station. { Hope I get it nailed this time ..... }

I am about finished going over the complete board! I have removed and tested just about everything.

If you have time can you check these and give me the part# on the chip.

Q441 Panasonic Part# B1JAEP000013 Physical Part# {Not sure I might have a mix up here}
Q452 Panasonic Part# B1JAEP000012 Physical Part# 45G128

Also D790 & D407 read strange out of circuit they show OL one direction and .191v the other direction this seem low to me? The Diode is marked 34 would you happen to know the full part# ?

At this point I have not found anything bad other than the usually parts.

I will be replacing Q661 with the one I received from eBay and be replacing D641 & D642 with the single diodes.

Q621 & Q622 (30F125) test good out of circuit but I might just wait and replace them with the ones I ordered from part simple.

Here's a list of stuff I am replacing right now.

Q661 - Shorted
Q402 - Shorted
Q421 - Shorted
Q422 - Shorted
Q423 - Shorted
D641 - Low Ohms (Was wrong diode Dual not Single)
D642 - Shorted (Was wrong diode Dual not Single)
Q701 - Open
Q702 - Shorted
Q818 - Tested good but just going to replace
IC773 - Tested good but just going to replace
IC691 - Tested good but just going to replace
Q608 - Tested good but just going to replace
Q647 - Tested good but just going to replace

I still have one more section on the board to go over and a few more transistor to pull to test out of the circuit.

[Alastair E]

Re: Panasonic sc tnpa5081 rebuild

While researching and drawing up shopping-lists for my various SC boards--including the one I killed, Ive found summit interesting.

On one board the usual DG502 has in its place a RJP56F4A, while the DG402 has a RJP43F4A
in its place. Looks to be an original unmolested board, so reckon they must have been made with those subs...
I have quite a few of these RJP types, but no DG types except the SMD DG301, not suitable for the 5081

The troublesome to locate 'C541' Buffer is available from RS Components UK in VSSOP package size exactly as fitted--Same Tosh part-number as earlier in this thread...

Most of the small parts like Q701, Q702, IC773 etc are available from Farnell, and cheaper than utsource--Probably more dependable oem parts rather than a possible fake--Much faster too if you're in the UK....

Ive been looking at the 30F125 parts, thinking that an FGPF4633 may sub if needed, 330V, 300A I/p (I have 20 odd of these but no 30J125...)

A quick word on test-meters. As has been mentioned earlier in this thread, You get so used to how a certain model/make meter react with different parts. This was demonstrated to me earlier this evening while checking some backlight LED's.

I usually use my Beckman Tech 310 (30 odd years old, been very heavily used and abused, still working well) and know exactly how it will react, --one way on diode-mode will make a good LED glow nicely. The Cheapo thing I have here at home gives totally different readings--and No illumination of good LED's....
--I think the Fluke77 I have is much the same,--Never did like that meter--Even though I had it for free....

[dolivas27]

Re: Panasonic sc tnpa5081 rebuild

Ok after doing some looking around it looks like the D790 & D407 are this part# does this look right to you guys?

Part found on AliExpress
http://www.aliexpress.com/item/3000p...0-e4fc7406f29d

Should convert to this ROHM part.
http://www.mouser.com/ProductDetail/...g1LcysAw%3D%3D

On the 'C541' Buffer you mentioned would this not work as a sub / direct replacement?
http://www.mouser.com/Search/Product...74VHC541FT(BE)

I still need the part numbers for these if anyone has them.

Q441 Panasonic Part# B1JAEP000013 Physical Part# {Not sure I might have a mix up here}
Q452 Panasonic Part# B1JAEP000012 Physical Part# 45G128

Here is a picture of the D790 & D407

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

Ok after doing some looking around it looks like the D790 & D407 are this part# does this look right to you guys?

Part found on AliExpress
http://www.aliexpress.com/item/3000p...0-e4fc7406f29d

Should convert to this ROHM part.
http://www.mouser.com/ProductDetail/...g1LcysAw%3D%3D

On the 'C541' Buffer you mentioned would this not work as a sub / direct replacement?
http://www.mouser.com/Search/Product...74VHC541FT(BE)

I still need the part numbers for these if anyone has them.

Q441 Panasonic Part# B1JAEP000013 Physical Part# {Not sure I might have a mix up here}
Q452 Panasonic Part# B1JAEP000012 Physical Part# 45G128

Here is a picture of the D790 & D407

TC74VHC541FK, TC74VHC14FK are OEM number for the 14 & 20 pin devices. problem is the package and I've looked pretty hard. To my knowledge only Toshiba make them and some of these lines are becoming obsolete out of production too. Example the HA Toshiba schmitt invereter but TI have a direct replacement.

Got nothing on those diodes as I've never needed to touch them. Q441 & 452 are 45G128 but one may have a R stamped on it

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

While researching and drawing up shopping-lists for my various SC boards--including the one I killed, Ive found summit interesting.

On one board the usual DG502 has in its place a RJP56F4A, while the DG402 has a RJP43F4A
in its place. Looks to be an original unmolested board, so reckon they must have been made with those subs...
I have quite a few of these RJP types, but no DG types except the SMD DG301, not suitable for the 5081

The troublesome to locate 'C541' Buffer is available from RS Components UK in VSSOP package size exactly as fitted--Same Tosh part-number as earlier in this thread...

Most of the small parts like Q701, Q702, IC773 etc are available from Farnell, and cheaper than utsource--Probably more dependable oem parts rather than a possible fake--Much faster too if you're in the UK....

Ive been looking at the 30F125 parts, thinking that an FGPF4633 may sub if needed, 330V, 300A I/p (I have 20 odd of these but no 30J125...)

A quick word on test-meters. As has been mentioned earlier in this thread, You get so used to how a certain model/make meter react with different parts. This was demonstrated to me earlier this evening while checking some backlight LED's.

I usually use my Beckman Tech 310 (30 odd years old, been very heavily used and abused, still working well) and know exactly how it will react, --one way on diode-mode will make a good LED glow nicely. The Cheapo thing I have here at home gives totally different readings--and No illumination of good LED's....
--I think the Fluke77 I have is much the same,--Never did like that meter--Even though I had it for free....

I have not seen the RJP yet on a 5081 but in the same locations on the 5105 they do. I have not tried it yet but don't expect any issues using either the Panasonic or Renesas IGBTs.

That FGPF4633 I was thinking too could sub like you say. Or FGPF4536 which I have for the S30 board

I can say that on the 2011 models with SMD IGBTS , the smaller packaged FDG4536 I have used in place of 30F131 & the RJP30H2. The 50U30 (30F131 replacements) has completed 12 months of faultless running.

The 50ST30 with I subbed both with the FDG4536 IGBT is running well daily but it's only been a month now we've been using this TV.

[dolivas27]

Re: Panasonic sc tnpa5081 rebuild

TC74VHC541FK, TC74VHC14FK are OEM number for the 14 & 20 pin devices. problem is the package and I've looked pretty hard. To my knowledge only Toshiba make them and some of these lines are becoming obsolete out of production too. Example the HA Toshiba schmitt invereter but TI have a direct replacement.

Got nothing on those diodes as I've never needed to touch them. Q441 & 452 are 45G128 but one may have a R stamped on it

I was in contact with Toshiba and that is what they told me would be a direct replacement for these TC74VHC541FK, TC74VHC14FK

Here's the datasheet and the package looks the same.

http://toshiba.semicon-storage.com/i...csa&lang=en_us

I have some 45F128R in stock can I use these for the 45G128 ?

Once I have this repaired and ready to power up can I try to power it up with out the SS board connected?

So far everything else on the board it testing good. I don't know what to think at this point but I have a funny feeling the larger Screen is needing more current and it might have pushed the diodes I installed to far.

Oh on the diodes they are Schottky Diodes so they should test low like the reading I gave earlier so I am going to say there good.

We will know in a few days.

So I have question if a diode is rated at 300V 20A but you push the voltage to 330+ what does that do to the current rating?

Thanks again for the help.

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

I was in contact with Toshiba and that is what they told me would be a direct replacement for these TC74VHC541FK, TC74VHC14FK

Here's the datasheet and the package looks the same.

http://toshiba.semicon-storage.com/i...csa&lang=en_us

I have some 45F128R in stock can I use these for the 45G128 ?

Once I have this repaired and ready to power up can I try to power it up with out the SS board connected?

So far everything else on the board it testing good. I don't know what to think at this point but I have a funny feeling the larger Screen is needing more current and it might have pushed the diodes I installed to far.

Oh on the diodes they are Schottky Diodes so they should test low like the reading I gave earlier so I am going to say there good.

We will know in a few days.

So I have question if a diode is rated at 300V 20A but you push the voltage to 330+ what does that do to the current rating?

Thanks again for the help.

afraid that's bad info on their part. The suffix , FT, FK etc directly relates to the package. Yes , electrically that is the same but there is no way a TSSOP package will populate those locations!

On these later boards they're VSSOP, if they stuck with TSSOP as in the earlier pre - 2010 boards it would be easy as there are heaps of manufacturers.

TSSOP is 1.6mm longer, 2.4mm wider roughly

I would just use whatever 45G128 you have.

The G20,25 guide suggests removal of ss11 and or ss33 TV should turn on with no errors.

I don't understand the diode question. I expect if you went outside the limits in either volts or amps the device would fail.

Personally I think they use higher voltage ratings to improve longevity but they all appear to be in the 20A range. This is out of my area of knowledge

[dolivas27]

Re: Panasonic sc tnpa5081 rebuild

afraid that's bad info on their part. The suffix , FT, FK etc directly relates to the package. Yes , electrically that is the same but there is no way a TSSOP package will populate those locations!

On these later boards they're VSSOP, if they stuck with TSSOP as in the earlier pre - 2010 boards it would be easy as there are heaps of manufacturers.

TSSOP is 1.6mm longer, 2.4mm wider roughly

I would just use whatever 45G128 you have.

The G20,25 guide suggests removal of ss11 and or ss33 TV should turn on with no errors.

I don't understand the diode question. I expect if you went outside the limits in either volts or amps the device would fail.

Personally I think they use higher voltage ratings to improve longevity but they all appear to be in the 20A range. This is out of my area of knowledge

Not the first time a manufacture has given bad info....

Well that is kind of what I am thinking the dual diodes I installed were only rated at 300V 20A and if I am reading the schematic right there would be more than 300V on the diode especial at turn on.

Well it's either the diode problem or a bad panel as everything else it testing out good.

Also these are listed as two different part numbers I wonder if one is a R and the other is not as one have the leg bent back and the other froward.

Q16441 B1JAEP000013 TRANSISTOR
Q16452 B1JAEP000012 TRANSISTOR

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

Not the first time a manufacture has given bad info....

Well that is kind of what I am thinking the dual diodes I installed were only rated at 300V 20A and if I am reading the schematic right there would be more than 300V on the diode especial at turn on.

Well it's either the diode problem or a bad panel as everything else it testing out good.

Also these are listed as two different part numbers I wonder if one is a R and the other is not as one have the leg bent back and the other froward.

Q16441 B1JAEP000013 TRANSISTOR
Q16452 B1JAEP000012 TRANSISTOR

I never found what the "R" meant but that is the conclusion I reached and have stopped worrying about it ages ago. These parts would have been made for Panasonics needs, pre-cut and bent so it makes sense to have a different part number.

If it were panel I 'd expect the buffers to blow, I don't see how they are ok but the SC keeps blowing once connected to them.

[dolivas27]

Re: Panasonic sc tnpa5081 rebuild

I never found what the "R" meant but that is the conclusion I reached and have stopped worrying about it ages ago. These parts would have been made for Panasonics needs, pre-cut and bent so it makes sense to have a different part number.

If it were panel I 'd expect the buffers to blow, I don't see how they are ok but the SC keeps blowing once connected to them.

So you think the new buffers are still bad? They measure out good but I guess anything is possible.

Hope to be ready to test it soon I have went over the complete board and found some other interesting bad parts. I will update later on these.

I don't know what I am going to do about the Q621, Q622 (30F125)

The parts test good out of circuit but after reading everything on the forum you seems to be adamant about them being bad even though they test good in diode mode.

The ones I have from utsource look suspect to me and the ones that I replaced the bad ones with the first time were out of a TNPA5764 board that was good. These still test good out of circuit.

If you have some 30F125 on hand could you ohm them out for me please.

I have some on order but who know when they will get here.

I also have a feeling that the Q661 (RJP63F4A) that I also received from utsource were bad I will know more on this for sure later this week when I can do a curve trace on a known good one and the current supply I have on hand.

I see another 50" up for sale and might go and get it today.

Also the board I am working on is from a 54" TV has anyone repaired one of these boards and got it to work?

From reading the forum it looks like all the attempts to repair these have failed. I have a hunch why but will not know for sure just yet until I figure out what to do with the Q621 & Q622