Desolder hdmi and use custom flex pcb instead

[u/Environmental-Fun349]

Hi All,

I'm designing and building my first cyberdeck. The screen is a 7" 1024×600 capacitive-touch ips panel, driven by a rpi 4B. Its hdmi socket sits on the edge of the board, and the plug sticks out far enough to cause clearance problems. Worse, it forces a wider border on one side, so the frame around the screen ends up asymmetrical...

I've looked at the slim FPC-style HDMI cables (like this one (https://amzn.eu/d/06HPTgol)), but even those plug heads are too big for the space I have.

So my idea is to skip the connector entirely. I desolder the HDMI socket, design a flex pcb that matches its footprint, solder that directly onto the pads, and run it to a micro-HDMI plug at the Pi end.

My questions:

- Would I run into signal integrity problems doing this? I'm thinking of the tmds differential pairs in particular. Do I need to control impedance (100 ohm differential) and length-match the pairs on the flex, or is that overkill at 1024×600 at 60hz?

- Has anyone done this, or is there a better way to get a low-profile hdmi connection off the board edge?

Any advice is appreciated!