APNAW - I told you I dad an idea...

Author	Message
Sasquatch Guru Joined: 08/05/2020 Location: United States Posts: 362	Posted: 03:13pm 04 Nov 2024         javavi said   Talk about the minimum length of the HDMI tracks on the board is untenable since the cable is much longer, here it may be a matter of their identical length, but it is not so critical. I think the issue here is not the trace length but the impedance matching to the cable and the terminating resistors on the other end (and yes, keeping the length of the individual traces matched)  Keeping the unmatched trace length short should help the integrity of the high speed differential signals.  Note that it is possible to create PCB traces with the proper impedance, but it requires proper trace width, spacing, ground plane, board thickness etc.   javavi said   You can also try to fit a VGA video output there, connected in parallel to the HDMI with its own resistors. This solution has already been tested in other projects and does not interfere with each other's work. This is an interesting idea, my question would be, tested at what resolution?  We have already seen that HDMI at lower resolutions (i.e. lower frequency HDMI signals) is much more forgiving.  It wasn't until Peter implemented the higher horizontal resolutions that I started seeing issues with the HDMI signals on my test setups. Edited 2024-11-05 01:34 by Sasquatch