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[Solved] Another screen problem :(

Posted: Sun Jan 13, 2019 8:33 am
by Mike9490
Hello everyone,
I'm trying to create a game boy zero with a bigger screen (4.3'') (the other components are the same XD).
The screen is this one: https://it.aliexpress.com/item/Jansite- ... 4c4dc83HDs
I try to find out the 5V pin with my multimeter but i only find 3v tensions on the pin (or 0,2v).
Image

Image

Someone can help me?

Re: Another screen problem :(

Posted: Sun Jan 13, 2019 10:54 am
by infinitLoop
i think you need to get a better picture of the chips with legs on them. it may not seem like it, but there are chip codes printed on them, if you can get the zoom and angle/light just right, you can get a picture of them on your phone, but it's not easy. it might be that that size screen doesn't do the 5v conversion too.

Re: Another screen problem :(

Posted: Sun Jan 13, 2019 1:11 pm
by Mike9490
I write all the components that are unreadable in the image.
Image

do you think it's impossible to convert this screen?

Re: Another screen problem :(

Posted: Sun Jan 13, 2019 8:29 pm
by infinitLoop
i can't say for sure, but none of those look very promising. you'd have to test the pins, but if you did that and none were reading 5v, then it might not have that voltage converter. have you tested to see if it'll just power up on 5v? if it does, it might be ok to run it like that, just inefficient.

Re: Another screen problem :(

Posted: Mon Jan 14, 2019 1:54 am
by Mike9490
I try using the 5 V but obviously it doesn't work...
I'll use the multimeter another time and i hope to find some 5V that i don't see :(

Re: Another screen problem :(

Posted: Mon Jan 14, 2019 3:49 pm
by correia5022
Well, not sure if it would work, but i did something similat into some audio amplifier boards and worked:
See that 10V cap? i'm sure there is a 5v rail passing there. i connected my 5v power supply to it and works.
ATTENTION: i used in audio amps, not in that type of pcb's. (but it wont hurt at least measure its voltage... confident it will read 5v)

Re: Another screen problem :(

Posted: Wed Jan 16, 2019 3:54 am
by Mike9490
correia5022 wrote:
Mon Jan 14, 2019 3:49 pm
Well, not sure if it would work, but i did something similat into some audio amplifier boards and worked:
See that 10V cap? i'm sure there is a 5v rail passing there. i connected my 5v power supply to it and works.
ATTENTION: i used in audio amps, not in that type of pcb's. (but it wont hurt at least measure its voltage... confident it will read 5v)
Thanks for the reply,
I will try as soon as possible because i give my multimeter to a friends.
I hope to find that 5v somewhere on that board.

Re: Another screen problem :(

Posted: Fri Jan 18, 2019 8:20 am
by correia5022
So have you measured the voltage across the cap?

Re: Another screen problem :(

Posted: Mon Jan 21, 2019 7:58 am
by Mike9490
correia5022 wrote:
Fri Jan 18, 2019 8:20 am
So have you measured the voltage across the cap?
At 20.00 i'll take back my multimeter and try, thx for che reply :mrgreen:

Re: Another screen problem :(

Posted: Mon Jan 21, 2019 1:36 pm
by Mike9490
correia5022 wrote:
Fri Jan 18, 2019 8:20 am
So have you measured the voltage across the cap?
I try but i can't find any 5v near the 10V cap ( just a 3.3V on the pin of that capacitor)..... :(