50" LG Y-sustain IPM modules

[father_fixit]

Re: 50" LG Y-sustain IPM modules

By the way to remove the IPM modules from the board with minimal damage, I used an old Hand Copper made for soldering copper and lead sheet metal flashings for roofs, chimneys and plumbing pipes. I cut a slot along one corner of it with a hack saw. I let it sit and heat up with my propane torch blowing at it. I pointed the slot upward to create a trough and filled it with solder. I set the board over the hand copper with pins down and lowered it down so one row of pins dipped into the molten solder. A little wiggling and pulling and that side pulls out.

[mbates14]

Re: 50" LG Y-sustain IPM modules

Yea, probably coppell TV repair.

Anyway, Can you send me that PDF? some of the pages in the scribd one isnt too clear.

thanks.

Im still fighting with this other PDP50X3 I have. I replaced the IPMs again with C series, fired it up and nothing. no pix. checked voltages, they are all present. no blown fuses. but i have not checked the 18V supply while chips are in place and secured connected to set yet either... need to check that. I had my first sustain board socketed. so i could pullt he chips right out and push them right back in. But I removed them for the simple fact of added capacitance may cause problems.

maybe blew the control board out too.. who knows.

[father_fixit]

Re: 50" LG Y-sustain IPM modules

My 50HP66 is working great! Found a bad FET on lower Y buffer board p/n FQB46N15. Couldn't find an exact replacement from a parts house so I stole one from another project plasma ( LG 42"). That restored my VSC voltage. Then I bought a pair of C series IPMs from an ebay vendor from Texas, installed them in my YSUS, and Wa-Hoo - 50" Plasma JOY! I read many recommendations about replacing the IPMs in matched pairs and so far I am a believer as many people have replaced just one, only to have it fry within minutes. Mine has been running great for days. Not sure if it's acceptable to name the vendor. By the way, it seems that the 16.3v on the 18v circuit is OK by my experience and confirmed by the experienced vendor.

[Cornboats]

Re: 50" LG Y-sustain IPM modules

I was interested to read that you repaired the Ipm. I've got a blown ipm from plasma 42".

It hard to identify blown component because there nothing left-big bang, but 4 legs are remaining. There are also identical legs connected to a 10mm square component adjacent.

is this similar to the mosfet you fitted I wonder.

[father_fixit]

Re: 50" LG Y-sustain IPM modules

The manual in the link I posted above shows a power distribution schematic of the boards. I have the .pdf file downloaded and saved.

[PowerAmpFreak]

Re: 50" LG Y-sustain IPM modules

I'm quite interested in those IPM's. I'm working as a power electronics designer, mostly smps and other applications. Anyone have a schematic of a discrete built Y-SUS board? Or better an IPM?
What I've seen so far, this is quite straight forward stuff.

[Wizard]

Re: 50" LG Y-sustain IPM modules

Thank you!!

Cheers, Wizard

[father_fixit]

Re: 50" LG Y-sustain IPM modules

What's the IPM?

The IPM (Intelligent Power Module) is the large hybrid chip under each of the two large heatsinks on the YSUS and ZSUS boards.

Role of IPMs

1. Generate Sustain Waveform (square wave) – SUS IPM
2. Energy Recovery Function (for saving power) – ER IPM

**found info in this manual http://www.scribd.com/doc/16077007/L...07-VG-Training

I am wrestling with a Toshiba 50HP66 with a 50X3 panel. The 18v on the YSUS measures 16.3 like others posted. On the ZSUS it measures a solid 18.0. I hope someone figures this out. I would rather repair at component level than $200 for a replacement board, but based on experiences of others, I am afraid to install new IPMs only to watch them blow in a few minutes.

[Wizard]

Re: 50" LG Y-sustain IPM modules

Now that more clear.

This IPM module you can pull this 18V module and juice the 18V pins on the board using adjustable DC external power supply and find the overload.

Cheers, Wizard

[PowerAmpFreak]

Re: 50" LG Y-sustain IPM modules

I'm curious how you actually rebuilt the IPM?
When checking a discrete Y-SUS board, I can actually see three "legs" of halfbridges with corresponding IR bootstrap gate drivers (like in class D audio amps). So, what can cause a class D amp to dissipate heat?
if there are bad gate drive supply or cross conduction in the main switches, maybe this can be the case even on a driver board for a plasma TV.

[mbates14]

Re: 50" LG Y-sustain IPM modules

I forgot to note, there is an 8-pin PWM control IC that drives that 18v regulator. they are all within the same spot of the 18V regulator.

What i do is have both IPMs removed, have the bare board sitting on the bench, and I hook a lab power supply up to the 5V rail, set it to 5V, and test my 18V output.

this is the safest way to test the output of the regulator, without having all these rampid high voltages around while testing in the set, risking probe slippage and blowing shit up like i normally do.

I have the pictures, I just have to get them off of the camera. besides, I rebuilt the ER IPM and she held up just beautiful. its the SUS IPM that blew, but i stuck a regular unrebuilt known good ER IPM in its place to eliminate that as a factor, before it blew out, and it blew out anyway.

[mbates14]

Re: 50" LG Y-sustain IPM modules

im back. the buffer ICs eventually totally took a shit after a few minutes on this TV, the guy pretty much got a new one so i got stuck with this one. So basically, I got a junk chassis with a good panel. looking for a panel-swap candidate for this little/big guy. However.......

I removed the sustain module and stuck it in another 50X3 with blown IPMs and it ran for about 5 minutes before the IPM blew out again.

18V is hanging around 16.3V on both Y sustain boards. so im suspecting that low voltage is causing the issue. but i did capacitance and ESR checks on those SMD caps and through hole caps, they are all fine. thats not the cause of my low B+ Something else is.

Also, the 18V is derived from the 5V supply on the board, via a step-up boost converter circuit. this circuit resides directly under the ER IPM heatsink. This was IMHO, the most stupid idea ever. but i guess since the toshiba sets that I have, used sony power supplies, they had to do it this way. i guess... who knows.

The ER IPM survived the re-failure of the SUS IPM.. So i got 2 good ER IPMs, (1 rebuilt, 1 stock). and no good SUS IPMs


So... the only thing left to do is remove the Z-sustain from the first 50X3 that is junk now, and remove its IPMs to be placed into the Y-board again... problem is, i gotta find out whats going on with that 18V supply, or guess what, shes gonna blow again.

[PowerAmpFreak]

Re: 50" LG Y-sustain IPM modules

Last time I removed one IPM I used a special compressed air de-soldering gun which we have in our shop, also we have super wide soldering irons which is 2 inch wide. This covers most of the pins on the IPM, one side at a time.

[Wizard]

Re: 50" LG Y-sustain IPM modules

What's the IPM? And where do 18V comes from? On samsung, the 15V comes directly from the main power supply board.

Cheers, Wizard

[father_fixit]

Re: 50" LG Y-sustain IPM modules

I will upload the pictures of what I did to the J016 module a little bit later.

Did you post the pics?

[cadiman]

Re: 50" LG Y-sustain IPM modules

There are posts on this topic.
I break off the old chip at the screw with the twist of a screwdriver. You can loosen the screws a bit with needle nose vicegrips to get a screwdriver between the chip and heat sink. Cut each pin one by one then desolder each pin wth a butane iron and clean with a small drill bit.
I solder the chip in then install the heat sink last with small allen bolts and nuts.

I was not in a hurry to do another one!
Good luck!

[fastvideo]

Re: 50" LG Y-sustain IPM modules

Hi, mBates

What temperature soldering iron are you using; or, a better question; how are you removing the IPM's?

I have had difficulty desoldering them. I have a 50x3 ( in a maxent case) that has been my project for a couple years. But, as an engineer, it only makes sense to repair the components instead of replacing an entire card, as I have been doing.
I believe I'm slowly losing the Erase IPM on my Sustain board, but I can't seem to easily remove it without damage.

What do you think?

Turning

I have the same question here.
It took me at least 45mins to remove it and with 2 traces damaged.

[Turning]

Re: 50" LG Y-sustain IPM modules

Hi, mBates

What temperature soldering iron are you using; or, a better question; how are you removing the IPM's?

I have had difficulty desoldering them. I have a 50x3 ( in a maxent case) that has been my project for a couple years. But, as an engineer, it only makes sense to repair the components instead of replacing an entire card, as I have been doing.
I believe I'm slowly losing the Erase IPM on my Sustain board, but I can't seem to easily remove it without damage.

What do you think?

Turning

[mbates14]

Re: 50" LG Y-sustain IPM modules

found 2 of the SMD power MOSFETs on the lower y buffer shorted. Replaced, and shes playing once again ;-)

[mbates14]

Re: 50" LG Y-sustain IPM modules

Victory was short lived...

But i think its my fault though...

It was working beautifully, turned it off and unplugged it. then went to go plug it back in and turn it on. i got nothing but white vertical bars where the menu is supposed to be.

if i input a signal, i get alot of blue mal-discharge and the TV shuts down.

i think its from removing and reinserting the ribbon cable into the sustain module 50000 times. because if i twist or push on that cable a little bit, the screen will change from white vertical bars with some blue mal-discharge, to almost non-visible vertical white bars and flashing/beating raster.

I guess its just the cable. But ill find out tomorrow for sure.

so im gonna try and locate another ribbon cable, as that carries all the y-scan signals, and sustain/ER signals. which will cause the vertical white bars. I checked the IPMs again and they didn't fail. no shorts. so its gotta be something stupid.