I'm designing a 3V button cell battery powered device. I want it to beep or click or just make any noise at some times just loud enought to be heard across the room.
I've made a prototype working on 12v - it's just an opamp comparator that goes high and low and i've connected a piezo speaker to output of opamp with a cap in series. It makes clicks when opamp goes high or low and they are just loud enough, but when i lower voltage to 3v, i can barely hear the speaker.
Can anyone suggest me a solution?