I come in search of help. I'm working on modding an lcd screen for inclusion in my case design. I'm trying to determine the feasibility of doing a VGA mod on this lcd. It's not a PSOne lcd, I know those are easy to VGA mod but I'm stuck with what I have. I would like to post some pics but that will have to wait as someone seems to have misplaced my digicam. However, I'll describe what I've figured out thus far.

There are two primary circuit boards within the lcd housing. There is a controller board attached to the lcd screen itself and the backlight (just one board, no separate pcb for the backlight). Then there is another board into which all inputs go, power, video, audio, adjustment buttons, etc.

Between these two primary pcbs are just two cables. The widest cable has 14 pins. The second cable has just 9 pins. If I unplug the 9 pin cable from the lcd controller board everything seems to work fine except for the adjustments (brightness and color). So, the entire picture signal and power gets to the lcd controller over the 14 pin cable.

At first, I counted 14 pins and went . VGA connectors have 14 pins. But I've never heard of piping power over a VGA connection. So, what am I to do? I've tried searching for some sort of schematic or pinout online, but have come up with nothing thus far. I've tried to follow traces and find clues as to the purpose of each pin until I went cross-eyed.

I'm no electronics expert yet, but if someone could throw me a bone and recommend a way to figure out which pin does what, I would be very grateful. Do I require a pinout or is there another way?

Maybe something like this could help you figure it out...
eBay: VGA to S-Video 4-pin / RCA Adapter Cable for PC TV (item 320133466976 end time Jul-03-07 08:13:40 PDT)

Thanks for the suggestion Beetleman. Something like that might help a bit. However, it looks like there is no circuitry in that adapter to combine the component color and sync signals into chromaa/luminance needed for RCA/S-Video. The description mentions that your video card must support tv-out through VGA. It seems that would suggest that any conversion of the signal must happen in the video card with the vga pins simply carrying a different signal than they do for a typical vga pinout.


I'm going to do a bit more research on the different signals to learn how the components are combined, synced, etc. Maybe I can figure out what these circuits do and how they process the signal before sending it to the lcd. Then if I can somehow figure out what some of the pins are for, maybe I can make an adapter. This mod may take a while, but I'm sure I'll learn a helluva lot in the process.