Good idea. I was starting to lean towards quick solder options with my design as well. Either with pin headers or QSBs. A different design would be needed for each encoder but it would make installation a lot easier. This is not possible with the BT9101 encoder as it is a fine pitch 160 pin QFP.
I made a mistake with my design by including a parallel termination resistor AND a series termination resistor. Only one is needed, my design was effectively triple terminating the signals, oops. Analogue Devices use parallel terminating resistors in their designs while the online community advocate series resistors.
It is advisable to place the 470ohm resistor close to the console end as possible but as you said, the AC coupling caps (220u - 1000u) can go either end on the line.
This page has some good info on reducing parasitic capacitance in video signal lines https://shmups.syste...php?f=6&t=55948
Viletim knows all. I've seen that page many times in my research.
All the extended datasheet says is something like "the ADV DACs are designed to either have a single or doubly terminated 75 ohm load (double being preferred)"
The datasheet doesn't mention series at all. There must be a reason.
The equation for IOG is the same as that for IOR and IOB when SYNC is not being used, that is, SYNC tied permanently low.
Means I should be able to switch Blue and Green as long as I don't have sync.
I have to reapply VREF to get accurate measurements right now I am hitting a little over 2V (unterminated) but still it should be around 1.4v
VPA536 is a 68 pin PLCC I think it is 25x25mm but IDK. I already made the header off of a PCB lib of another 25x25 68 pin PLCC we will have to see how that lines up.
Progress so far:
Although it looks very similar to the last one there have been many changes. Probably one more set of edits before its ready to order.
Let me test against the VPA536 then we will know whether the pins will line up for either version of this.
If I remember correctly the N64 HDMI mod has one of those quick solder things and it is similarly spaced 120 pins.
I wonder if there is a way to interface it so that all revisions can use the same kit without much fuss.
Id have a square mask that broke out those connections to solder-able pads meant for ribbon cable.
ribbon cable into 1.27 spaced holes seems clean enough then you can use the same base kit for everything only changing that mask (i dont even know what those are called.
Edited by the_crayon_king, Sun Oct 22, 2017 4:32 PM.