Hi!
Is there any sort of multichannel over-voltage protection module or IC for digital I/O?
Let's say I have my DIY controller PCB with 32 pushbuttons and 32 relays. The buttons and relays are wired up 'outside' and exposed to all sorts of 'intruder' attacks like applying AC mains to inputs/outputs (up to 240VAC I guess), or high-voltage shocker strikes, shorting wires etc.. I need my pcb to survive the attack (even if pushbuttons/relays are destroyed).
Initially I thought of putting a separate PTC+TVS+pcb-spark-gaps (or GDT?) protection on every channel, but soldering dozens of those are kinda unfavourable.
Is there a better solution? How to reduce the number of components and pcb space required?
P.S. There are ULN2004-like ICs for inputs and 'smart-protected' switches for outputs, but I suppose they won't survive on its own?