I want to use an Ardiuno to drive a Matrix of TO-220 Mosfets triggering mechanical relays instead of LEDS.
I am making an array of glow-tubes (read: flickery, purple lightbulbs) as a dramatic screen interface for an art installation. I would prefer to use mechanical relays for aesthetic appeal (clickity clack!). I will build a 4*4 prototype, then a 16*16 or larger according to funding etc.
I want it to be an expandable design, so im considering multiplexed control rather than dot matrix.
1: At multiplexing speeds, will a mechanical relay coil hold?
I am switching at full coil voltage, so when multiplexed the current might be alright for holding. Are there any tricks like putting in a capacitor somewhere that might fill up the tiny delay?
2: I will have a diode across the relay coil, but will jamming coils on and off at high rates create any kind of EM noise or current spikes I should be wary of?
3: Am I on the right track? I basically want a controllable lamp array, im using standard LED multiplexing designs because its readily available for arduino so I dont have to code it all aswell :D
Found an interesting discussion here on a technique using i2c and TPIC6B595 serial latches,