Samsung QN75Q60TAF Boot Loop fixed but no picture

[Nicktronic]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

!!! DO NOT CONNECT 3.3V TO PIN 9 OF CH341 otherwise the CH341 will burn in 5.0v selection. !!!

Did you install a jumper when setting 9 pin to 3.3v?

Yup, as the many sites and videos said to do. Crappy, so what does that mean? It will output 5 V to VCC of the SPI flash?

[lotas]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

Without a jumper it gives out 3.3v (for spi flash), with a jumper it gives out 5v (for eeprom 24Cxxx), but if you make a mod (with 9 pin, only for spi, then it is absolutely impossible to put a jumper). 5v then goes to 9 pin and that's it - the chip itself burns out.
It was necessary to do the mod only with power at 3.3v without a jumper for 9 pin.

[Diah]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

1- yours jumper the red wire enough don't do any more
2- use the program i later attached at my post #145
3- be sure the PCB of the chip sitting on the programmer pin 1 on 1

[Diah]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

yours photo

you should put the yellow jumper clip on pin 1 & 2 this is programmer.... and if you want to use the adapter as serial for log dump the jumper need to be at pin 2 & 3

[Diah]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

I checked every pin, cap, solder pad, test point etc on the board with LVDS and U cables removed and could not find a connection to anything from DT601 pin 5 and DT602 pin 5. Is it possible they are not used?

U ribbon you mean..... if yes... this ribbon should be connected so because the board sandwich, it may the pins go to end corner of the display.

[Nicktronic]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

U ribbon you mean..... if yes... this ribbon should be connected so because the board sandwich, it may the pins go to end corner of the display.

Yes, I understand but I checked DT601/DT602 pin 5 to all the pins of connector of the U ribbon at each end of the board.

[Nicktronic]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

Hmmm, @diah says use the jumper, @lotas says do not use the jumper lol. What do i do!?? At this point, I've tried all combinations and no luck. SPI is likely dead and if @lotas is right, the CH341 is dead. :S

[Diah]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

Hmmm, @diah says use the jumper, @lotas says do not use the jumper lol. What do i do!?? At this point, I've tried all combinations and no luck. SPI is likely dead and if @lotas is right, the CH341 is dead. :S

lotas talking on pin 9 of the IC dont connect it to 3.3V as some idiot on internet say... and he is correct dont .. just the red wire you did enough.

i am talking on jumper pins 123 .... take look downside its printed pin 1-2 programmer pin 2-3 TTL also you need to short pin 1-2 with jumper

[Nicktronic]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

lotas talking on pin 9 of the IC dont connect it to 3.3V as some idiot on internet say... and he is correct dont .. just the red wire you did enough.

i am talking on jumper pins 123 .... take look downside its printed pin 1-2 programmer pin 2-3 TTL also you need to short pin 1-2 with jumper

ah ok, thanks

[Nicktronic]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

So I bought another CH341A just in case i bricked the one i have like @lotas suggested.

Now, when I get the new one, DO I NEED TO DO THE MOD (lift pin 28 of CH341 and run mod wire from pin 28 to the middle pin of 3.3V regulator)? From the datasheet of the SPI, I see it cannot handle 5V.

[nomoresonys]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

.

[nomoresonys]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

CH341 has both 3.3 and 5v.: https://www.ebay.com/sch/i.html?_fro...volt&_osacat=0

[lotas]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

So I bought another CH341A just in case i bricked the one i have like @lotas suggested.

Now, when I get the new one, DO I NEED TO DO THE MOD (lift pin 28 of CH341 and run mod wire from pin 28 to the middle pin of 3.3V regulator)? From the datasheet of the SPI, I see it cannot handle 5V.

Yes, it's better to make this mod, because the chip itself will already be powered not by 5v, but by 3.3v and, accordingly, the signal lines between spi will also be at 3.3v, this is with a green board programmer CH341A (old revision) mod does not need to be done, everything is fine there , but it is better to make a programmer with a black board.

[lotas]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

For such a "green" mod is not needed. 28 pin is powered by 3.3v.

[lotas]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

Here are the latest drivers for the CH341A programmer.
CH341SER.EXE - self-installing archive with USB to serial driver.
CH341PAR.EXE - self-installing archive with multiprotocol interface driver (this is for programmer mode)

[Diah]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

- OP CH314 still working.. this will never die or kill
- GD25B32C I/O NOR Flash had leak. not shorted
- DT602 had leak
all above 2 & 3 points caused by Panel cells / COFs
- end result T_con circuit on MB as ( nomoresonys ) expected but its toasted

[Nicktronic]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

- OP CH314 still working.. this will never die or kill
- GD25B32C I/O NOR Flash had leak. not shorted
- DT602 had leak
all above 2 & 3 points caused by Panel cells / COFs
- end result T_con circuit on MB as ( nomoresonys ) expected but its toasted

So your opinion is that the panel has the problem and there's no way to fix?

[lotas]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

So your opinion is that the panel has the problem and there's no way to fix?

Not yet known.

[Nicktronic]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

Not yet known.

I think @diah is saying the T-Con circuit is toasted on the MB, do you disagree? New MB then?

- GD25B32C I/O NOR Flash had leak. not shorted
- DT602 had leak

I'm waiting for a new SPI Flash, should I also order a new DT602?

[lotas]

Re: Samsung QN75Q60TAF Boot Loop fixed but no picture

Remove DT601 and DT602 and all of them are not needed, they cause more problems.
After removal, check to turn on the TV without spi and 601, 602.