I'm thinking about replacing a USB 3 Micro-B receptacle (the wide boi, who ever thought of that garbage, srsly), on a board I'd like not to redesign from scratch, with an adapter board to a USB-C receptacle (that I would design). The device only requires USB 2.0 connectivity, thankfully (it's a keyboard, thanks for asking).
The existing connector footprint has 0.65mm pitch, 0.4mm wide SMT pads. I'm guessing castellation will be impractical at such small sizes (and hobby budget) and I'm thinking of using gold fingers on a Flex PCB, to solder across, instead.
I'm coming up short on finding similar designs, even though "Flex PCB soldered on top of existing board" seems to be a common pattern of the console modding community.
Any fedi #Electronics or #Modding experts have resources on #FlexPCB design gotchas?