Tc-p55st30 buffer board ic chip

[ricosavy]

I was wanted to see if any one had a better way to remove the ic buffer board chips.On panasonic buffer board for tc-p50s30 and tc-p55st30 the chips are hard to remove.I have tried to heat them but had no luck hot air gun usually burn the board and tracks.I have found that the ic chip is glued under it and can take the heat.I sent one board to have it fixed was told it had corosion and board was beyond repair and i asked for board back and you could see it was a failed attempt.After trail and error i realize the problem is the chip is glued under chip.So what i did was use a razor blade and cut the legs as close as i can to chip.Once that was done i used a pick to pry chip off using tape under pick so i would not damage the board.The chip was still glued pretty good to board but it came off.I had to be careful not to cut the board and had to make sure all legs had been cut.If any one has a easier way to remove them please comment since boards will probably become harder to get.here some pics

[ricosavy]

Re: Tc-p55st30 buffer board ic chip

Here pic with glue and legs removed just waiting for chips to arrive

[tw2005]

Re: Tc-p55st30 buffer board ic chip

I was wanted to see if any one had a better way to remove the ic buffer board chips.On panasonic buffer board for tc-p50s30 and tc-p55st30 the chips are hard to remove.I have tried to heat them but had no luck hot air gun usually burn the board and tracks.I have found that the ic chip is glued under it and can take the heat.I sent one board to have it fixed was told it had corosion and board was beyond repair and i asked for board back and you could see it was a failed attempt.After trail and error i realize the problem is the chip is glued under chip.So what i did was use a razor blade and cut the legs as close as i can to chip.Once that was done i used a pick to pry chip off using tape under pick so i would not damage the board.The chip was still glued pretty good to board but it came off.I had to be careful not to cut the board and had to make sure all legs had been cut.If any one has a easier way to remove them please comment since boards will probably become harder to get.here some pics

funny, we've been talking abut this in recent times and that was the same comments i gave someone regarding how that thermal sealant is forced under the chip in the manufacturing process.

I did whaat you said and cut the legs and got the chip off with brute force. The problem I then had was i did not get all that sealant off the tracks and when I went to desolder the legs with the heat and the sealant grabbing the track I tore them.

i have a couple of 5090 buffers I was experimenting with because they too are getting rare and expensive so I was keen to see what I could achieve but i failed.

I'll wait until some smart cookie works it out but i think the key is getting that goo offf clean. Someone suggested petrol(gasoline) sounded extreme though

[tw2005]

Re: Tc-p55st30 buffer board ic chip

Here pic with glue and legs removed just waiting for chips to arrive

that's a fine job although the top ic looks like one has lifted but still intact

[ricosavy]

Re: Tc-p55st30 buffer board ic chip

I will let you know the out come once i get the chips one thing i did notice is when using tip of soldering you have to take it slow and let the solder and glue melt a little other wise it will lift the pins.I think keep practing will make u better in time you should be able to do it no problem till some comes out with easy way to do it.

[tw2005]

Re: Tc-p55st30 buffer board ic chip

I was bored so I decided to continue practicing removing two more with much better results. 1 track did lift but still intact. I did read someone tried acetone saying it does not work, maybe on a different brand board but I found acetone does work.

This is a 5090 SU board, 50G20, 25 etc

Though it does not dissolve it , it does alter its properties and it comes off a lot easier. I just keep applting acetone and work it off the pins. then I cut them, then soak the ic again and it liftsoff very easy and clen in comparison of using nothing. I too used a pick and just rub it, the sealant flakes away nicely. A wooden tooth pick also is a handy item to get this stuff off .

will post some photos

[ricosavy]

Re: Tc-p55st30 buffer board ic chip

Looks good i think you keep perfecting your technique you will have no problems removing them in future

[tw2005]

Re: Tc-p55st30 buffer board ic chip

Looks good i think you keep perfecting your technique you will have no problems removing them in future

Thanks. after doing these I decided to have a look at and old Samsung upper buffer IC, the ones that are unobtainable (2007 era). Their silicone is so easy once soaked with acetone, I was gutted to find the IC that burnt, really burnt , tracks and board. That's the end of that TV- too hard,too expensive.

I was really impressed with both my last attempts. The track only lifted with the cleaning process, next one was perfect enough. The ICs for this board though $10 each and i have 1 set here with all 6 blown x 2. Not economic to repair yet.

[tom66]

Re: Tc-p55st30 buffer board ic chip

Nice work. I have never been able to remove one myself successfully. I have a few scrap buffer boards (shorted, usually cracked screens) I might try it on.

[tw2005]

Re: Tc-p55st30 buffer board ic chip

Nice work. I have never been able to remove one myself successfully. I have a few scrap buffer boards (shorted, usually cracked screens) I might try it on.

I think you should and use some acetone. Apparently mousepads don't like the stuff. I worked on a wooden board as the acetone will runoff or through the board especially those small holes under the IC. In fact next time I'm going to invert the board and put acetone through those for the ic removal.
I used a hobby scalpel, takes a bit of technique to get the angle and action right, go too hard and the tracks will get trimmed off. i think you can see in attempt 2 a couple may be trimmed a little

[flocko]

Re: Tc-p55st30 buffer board ic chip

Hi TW what acetone are you using , the 100% acetone nail polish remover? I get that from our pound shops over here or should I say the wife does. I read on shopjimmy that IC buffer chips Panasonic AN6389A,Samsung 3407F and SN755882 can all be used as replacements for each other, I for one did not know this ,so this could make replacing them cost lot less, as the Samsung 3407F can be had from China for less than £1each ,and I always have a stock of these for the 50" Samsung buffers. Flocko

[tw2005]

Re: Tc-p55st30 buffer board ic chip

Hi TW what acetone are you using , the 100% acetone nail polish remover? I get that from our pound shops over here or should I say the wife does. I read on shopjimmy that IC buffer chips Panasonic AN6389A,Samsung 3407F and SN755882 can all be used as replacements for each other, I for one did not know this ,so this could make replacing them cost lot less, as the Samsung 3407F can be had from China for less than £1each ,and I always have a stock of these for the 50" Samsung buffers. Flocko

Good to hear from you, seen very little activity here from you recently. I used fair dinkum aussie brand DIGGERS(cheap) 100% acetone UN1090. cost me $9 AUD 500ml.

I wish I could find some datasheets on these ICs though. I was thinking there'd be some subs for AN16524A as panasonic changed from those to R2A20250 in the 2011 models and I reckon there's a good chance they may work but not game to chance blowing a SC. None of what you suggest helps for this as they're HD chips.

Sorry RICO, we've hijacked the thread here a little from the ST30 models, interesting discussion though.

[tom66]

Re: Tc-p55st30 buffer board ic chip

AFAIK most buffer ICs can be interchanged. There are some exceptions, but a common pin-out is seen between them. Usually 96 channels/IC (12 ICs for 1080p or 8 ICs for 720p). But yeah, datasheets are hard to get hold of.

[ricosavy]

Re: Tc-p55st30 buffer board ic chip

i got the ic chips and installed them and it worked.I also took a chip of a tnpa 5336 herebis the pic.same technique use a razor blade and cut the legs as close as i can to chip.also i clean the leg as much as i can of the glue with acetone before i cut.one thing i forgot to mention when i am cutting i apply pressure on legs where they are soldered with my finger nail.So the legs wont get lifted during cutting.

[tw2005]

Re: Tc-p55st30 buffer board ic chip

so what was the cost of the ICs? I guess since these are impossible to buy or very expensive it's economical to do this?

[ricosavy]

Re: Tc-p55st30 buffer board ic chip

I ordered mine from china i think total cost was 30 for 3 chips.that included shipping the problem is as these get harder to find you have to choices down the road either fix what you have or part the tv out.the better you get the faster you will be able to repair them paying just 30 for parts is not bad.