Just picked up a 55 inch LG 4k OLED for $50!

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

The ATML eeprom is on this board. This looks promising except I'm not getting VCC so this would essentially be pointless. Obviously it's not reading eeprom.

Courtesy of Samygo

[tom66]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Btw for those wondering.

OLED is very similar to LCD.

It uses a TFT, each pixel consists of a transistor which regulates current through an OLED pixel. The organic emissive layer makes light when current flows through it... somehow... I'm not clear on this bit.

I believe the TFTs are still driven by gate and source drivers and the OLED pixels are connected to the drain of these devices, likely from the +24V supply.

I am not sure what, if any, power is dissipated in the COFs - I suspect it will not be much more than an LCD - though the panel will get warmer...

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

The panel gets quite warm right on the bottom all the way across. Almost hot to the touch. I have verified this on a few demo televisions at our local Best Buy

[Davi.p]

Re: Just picked up a 55 inch LG 4k OLED for $50!

I dont want to make so fantasy suppositions, i dont have seen schematics nor complete images of the board but if there is a parallel flash and a serial one i guess the serial one holds the standby softw. and a cpu can't go in to protection without executing a routine, if the ser.eprom is not getting power then no code executed, maybe you can buy a cheap eeprom programmer like ch341 on ebay and try to read the content of the ser.flash and see if it's good or a crust...

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Actually I have arduino. May be able to program with it. Never tried yet. It has usb capability.

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

But the serial eeprom should be powered to recognize firmware or execute commands.. This one is not. And yes there appears to be two eeproms. Maybe backfeed VCC at front end of eeprom??

[Davi.p]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Freak please be clear, flash memory are on thing (them stores firmwares) and eeproms are another (stores settings), i've never used an Arduino, ch341 are very very cheap, and if you repair tv you better get one or better a more powerful cheap programmer like TL866 or RT809F or others.. i was just say that, you say that mainboard gone into protection, but how can a st.by processor see the problems if it doesn't execute code? Why and how a processor exclude vcc to a serial flash? Anyway i'm wondering if a programmer could be useful, if the flash eprom is not powered then a processor can't execute code and so the content could be intact. Is there a schematic in the SM you uploaded?

"Maybe backfeed VCC at front end of eeprom??" Sorry i can't translate..

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

OK here are some pictures of the main board with the heat sync removed.

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

IC402 seems to be eeprom. IC9101 is serial data possibly? Anyway none of these are getting VCC

[Davi.p]

Re: Just picked up a 55 inch LG 4k OLED for $50!

I don't see well the marking on the chips, you make faster if you transcript here all the markings on the 8 pins ics, even that shrinked types..

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

These two.

[Davi.p]

Re: Just picked up a 55 inch LG 4k OLED for $50!

ATML is a eeprom, 25L33 is a flash, are there any other? Have you tested any pins of the flash for the vcc? Is the vcc pin of it connected to a fuse?

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Yes i cjecked vcc ot both. And I haven't seen any fuses.

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

The other guy settled on 60 bucks. He is bringing the broken OLED to my house right now.

So maybe if I figured this one out I can somehow get the other panel figured out somewhat, And in turn Put the guts from his TV on to the other panel that I removed from mine..

In turn I'm going to strip the cracked busted panel out of that one and take plenty of pictures of the ribbon drivers and Chip on film and driver boards that run the OLED panel since its rubbish anyway.

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Got the damaged one. Can somebody say oopsie. Shipping damage?

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Yes folks, it does have side gate drivers.

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

And here you have it! A look at the workings of an OLED panel.

Strikingly similar to LCD except the organic compound on the back side of the panel. Mated to the LCD.

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

The panel is for certain not designed to remove If you have to access the driver boards. It will crack. Believe it or not the whole thing is held in by double sided sticky tape in 8 areas.

I found the LCD layer to be extremely fragile like typical LCD's but the organic LED or OLED layer behind the LCD was super flexible

[tom66]

Re: Just picked up a 55 inch LG 4k OLED for $50!

It's a TFT layer...not quite the same as an LCD.

Interesting that the ELVDD power passes through the source drivers, and disappointing... is that the only supply path for ELVDD? (The 24V supply from the PSU, which supplies the current for the OLED pixels).

Also interesting that the pin-out of the drivers is similar to PDP address drivers, something LG would have had experience with. Unlike normal source drivers, there's a high-power path for OLED current. I was hoping that it would be supplied directly to the panel via a pair of dedicated pads.

[tom66]

Re: Just picked up a 55 inch LG 4k OLED for $50!

IC402 seems to be eeprom. IC9101 is serial data possibly? Anyway none of these are getting VCC

IC8100 is your eMMC device which holds the TV's operating system. It's a Toshiba part so bets would be that it's failed. They were notoriously unreliable after few erase/write cycles when used by my former employer.

IC1901 is probably for the FRC controller, which is some kind of advanced DSP. May also be a problem.