50" LG Y-sustain IPM modules

[mbates14]

Re: 50" LG Y-sustain IPM modules

Update:

SUCCESS!!!!

Put in the new IRFP250 MOSFETs into the old IPM.

Found 18v still 2v with neither IC in place.

Found the 0.15ohm resistor nearly open, output diode off inductor shorted. replaced both. supply went up to 5V but it was stuck at 5V.

Scoped the 18V regulator, i noticed there was no dwell period or flux line ring from the inductor. replaced inductor, scope reading was now correct.

18V supply restored.

Re-installed the ICs, and powered up the TV. WORKS!!! has a beutiful picture once again. no overheating or signs of stress detected.

my rework job paid off.... no more expensive IPM replacements. hehe.

So repairing the bad J016 and the bad parts in the 18V switching regulator fixed the set.

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

I also socketed the ICs. so if it ever needed replaced again, i can just pop the ICs out, do the repair/replace and pop in a new one.


I also fabricated clamps so the ICs just wont "fall out" from heat/vibration.

[cadiman]

Re: 50" LG Y-sustain IPM modules

The faulty 15-18v supply is what finished off my ipm on my 50 L/G The heat took out the caps. ( Z board ) My y board is still running. ( was replaced already ).

[mbates14]

Re: 50" LG Y-sustain IPM modules

18V supply to the IPMs read 2.3v. J016 overheats, so the culprit is probably J016 pulling too hard on the 18V supply.

removed J016 again, checked real close inspection, see a hole in both J016 MOSFET dies, reads shorted on the meter with both my old one and the new one. so the new one was already blown, the visible blown hole in the die is VERY hard to see without a magnifying glass, so it probably got mistaken as a good IC and tossed in the good pile. all of the die level diodes test fine, no leakages. they survived. only the MOSFETs died.

J015 looks ok. going to try a pair of IRFP250Ns tomorrow connected to the IC to replace the blown FETs, already cut the bonding wires. the resistors and diodes are not bad on the ICs driver bd. they survived as well. so the mosfet just popped/shorted without taking even the gate drive resistor out. it is still intact and good.

so the only conclusion is the gate driver IC is trying to drive the shorted mosfet, taking the 18V straight into ground. thus causing the overheating of the IC.

wish me luck....

[mbates14]

Re: 50" LG Y-sustain IPM modules

ok well, i bought the 2 new IPMs. the j015 and the j016.

the j015 and 016 i ordered looked ok physically, and tested physically fine with no shorts.

put them in, same problem. no picture, and the J015 heatsink stays cold. but a new problem crept up, the J016 starts to overheat, never did this before. All fuses check fine, all power is going into the sustain module. Maybe the 195v isnt making it to the J015 IC, but the 016 is overheating now. it wasnt before....

So i took the old J016, it physically looked fine, and dry diode checks dont reviel any shorts so i stuck the old one back in there. still overheats now. hmmm.....

but the J015 stays cold. I scoped the SUS-UP and SUS-DWN drive signals comming from the control board, they are present.

any ideas?

[cadiman]

Re: 50" LG Y-sustain IPM modules

If I think I am taking a risk I pay or bid low. I found an inverter board on ebay for 20 bucks with shipping. The curcuit board was a half inch longer than the box. The seller had 5 transactions. The board worked. I gave the seller positive feedback then sent him a nice friendly messege. Plainbill is correct.... as always. I wish I could see better than I look and listen better than I can hear....Wisdom is a wonderful thing!

Good advice Plainbill

[PlainBill]

Re: 50" LG Y-sustain IPM modules

I was afraid you were gonna say that. i dont use ebay for electronic parts anymore. ive been burned way too many times, already ordered a new sustain board on ebay, got it, it was bad, had to send it back.

and that wasnt the only time. hehe.

Look at the feedback rating of the seller, and his product line.

Buying a used sustain board from someone who has a 95% feedback rating selling mostly shoes is a bad idea.

Buying an IC from someone with a 99.7 % feedback rating selling electronic parts is pretty safe.

PlainBill

[mbates14]

Re: 50" LG Y-sustain IPM modules

Six auctions on eBay.

PlainBill

I was afraid you were gonna say that. i dont use ebay for electronic parts anymore. ive been burned way too many times, already ordered a new sustain board on ebay, got it, it was bad, had to send it back.

and that wasnt the only time. hehe.

[PlainBill]

Re: 50" LG Y-sustain IPM modules

Six auctions on eBay.

PlainBill

[mbates14]

I have a sustain module i removed from a 50" toshiba plasma, although i believe the panel is LG. along with all of its drive electronics.

it uses the yppd-j015b and 016b chips. one heatsink was cold to touch, so i removed the IPM and it is physically blown.

the other IPM, 016, gets warm to the touch so i didnt remove it.

anyone know where to locate these IC chips besides a broker in china?