Good news for me, the display works with 3.3V and 300 mAh :lol: :lol: :lol: :lol: :lol: :lol: So now i have 5V battery and i need to convert it to 3.3V, maybe using a lm3940 (if you know some other way, i'm ready to hear it :D ) The definition si very low (i can't even read the boot words and it's ...

Here the voltage of all Pin in GBAAC chip :cry: Damn... cant think of anything else but to use a step-up board to 12v... Good news for me, the display works with 3.3V and 300 mAh :lol: :lol: :lol: :lol: :lol: :lol: So now i have 5V battery and i need to convert it to 3.3V, maybe using a lm3940 (if ...

The raspberry itself gives 3.3 out of one of its GPIO pins. Just google the pinout. Maybe the power consumption of the screen is too high for this output. Do you have power values measured from your screen to compare with the pi 3.3 output specs maybe before trying? See this link about raspberry pi...

have you unsticked that controller board from the screen? Please do that. I have a similar board that has 5v and GND pads on the bottom of the pcb... On the bottom of the pcb: http://i68.tinypic.com/1zrb5.jpg I think i'll try to use the 3.3V on the VCC33 pin... (i have to find something that give 3...

Also, i think that GBAAC chip is the solution, because seeing the traces coming from 12v, goes through a Schottky diode, then an inductor then i think the cap and then that chip. SO, please measure the voltage across GND and the 1st pin of the right side of GBAAC (oposite side of that little stop) ...

Maybe stop to focus on 5.0V, maybe your screen runs on 3.3 Volts as you already measured on the cap. If it runs on 3.3V and the power consumption is not too hight you can resolve this voltage from the raspberry GPIO pins somewhere. Just google the GPIO pinout and try. Keep the drawn amperage in min...

correia5022 wrote: ↑

Mon Jan 21, 2019 3:58 pm

Can you take a better photo as each chip?

Here the photo.. i don't think i can do better

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).....

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

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 lea...