sudomod

Here's how i did the 5v mod.

Iivv wrote: ↑

Thu Sep 07, 2017 10:24 pm

Hey i just got this screen from gearbest but i noticed that is different from the old model i was wondering if anyone knows how to convert it to 5v if possible
Thank you

imageShow

I've used that screen on 4 separate occasions, once just on Wednesday this week. All 4 screens did not need any modification to work...

zeroboy wrote: ↑

Thu Sep 07, 2017 11:55 pm

Here's how i did the 5v mod.

You screen didn't work with 5V from the start? I guess if I run into one that doesn't work on 5V it's an easy mod.

Hi!

I bought the cheapest screen i could find, from here:

http://www.lightinthebox.com/de/kleine- ... TB20170724

On the box is written:

SP002775
SKU
S104804300001

Brightness, Contrast, Saturation and Hue are adjustable and there are two Composite inputs.
It cost 12 € plus shipping.

To mod it i connected 5V to the Transformer Chip and had to cut one side of the board to make it fit into the GB Case. For me the screen worked afterwards, but i dont know what exactly i cut away (i think its a coil). I just tried it out.
Also i needed to remove the buttons.

I connected +5V to the battery + and Ground (black wire) and AV1 (Yellow wire) to the Raspberry Pads. With ground to the battery it worked but had lots of distortion in the picture.

See the pictures for further details.

This is the same screen I have ..


Do you noticed the words been fuzzy or something similar ?

its not very sharp, if you mean this, but for the emulators this this was no problem, only in terminal.

and first i connected ground to my powersupply wich resulted in bad distortions, better connect it to the RCA pad on the pi (circular pad is ground, the other one is signal)

Hey guys,

has anyone seen this board or know what I would need to do to get it to convert to 5V?


The only 8 prong chip on the board is labeled
" MK
25Q40A1IG
1654 "

I have tried red wire to second from top left with and without black wire on second from top right. Nothing.

There is also two chips with M7 and SS14, i've tried hooking up pos and ground to both of those with no luck as well.

Without any modification the screen just flickers on and off showing the retropie startup.

I was able to get that screen working. Here is the other forum post on it.

viewtopic.php?f=46&t=4247

Just a gentle remainder that if you come across data for a screen that is not listed in the Wiki to please add it, especially if its about 5v modding.

Has anyone tried the Crystalfontz CFAF320480C4-035T? It says it runs off 3v. I know next to nothing about any of this. Just wanted to see if it was worth the try.

Bought on ebay
Board found in the screen wiki (variant 7), but this one works at 5v without any modifications (even as low as 4,5v).
It looks like they have changed the voltage regulator to XL1509 datasheet: https://files.acrobat.com/a/preview/d9f ... a2f9aa70b
You could still remove it to make it more power efficient (regulator is 82% at 5v), and feed it system 5v through pin 2 on the chip but imho this is not worth the effort. https://rover.ebay.com/rover/0/0/0?mpr ... 2241298189

One quick adition,

The screen is held by one little clamp, so removal is extremely easy!
No glue, no prying with screwdrivers, just remove one screw an it pops right out!