[Solved] Another screen problem :(

[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).




Someone can help me?

[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.

[Mike9490]

I write all the components that are unreadable in the image.


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

[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.

[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

[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)

[Mike9490]

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.

[correia5022]

So have you measured the voltage across the cap?

[Mike9490]

So have you measured the voltage across the cap?

At 20.00 i'll take back my multimeter and try, thx for che reply

[Mike9490]

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).....