Hi!
I have built a microcontroller project with an ATtiny2313 which drives a few 24Vdc relays. The switches of the relay turn on-off 230Vac loads. My question is that will ac voltage bring on noise to my pcb? Is it usual that a dc relay drives ac loads?
Regards
"My question is that will ac voltage bring on noise to my pcb?"
No it won't bring any noise. and if you are worry you may add a .01uF capacitor between Vcc and ground to act as a filter for any noise that may interfere with your circuit.