sjb741
Junior Member level 2
I have a commercial smoke detector which I'd like to use for experimental purposes. It uses a soic-16 chip by "SEMIC": CS2105AGQ-S1Z, TGAY2VU401L.
The piezo sounder is the type with 2 terminals (ground, brass and silver <--> ground, drive, feedback ?).
If the piezo has a resonant driver circuit (I can't tell, but it does use 3 wires) then I think brass is 'drive' and silver is 'feedback'. Or maybe it is simply driven by an H-bridge.
The piezo volume can be somewhat attenuated simply by squeezing between thumb and finger.
Ideally though I would like to be able to smoothly vary the volume. I was wondering whether a simple 'rheostat' in series with ground would work and if so what a sensible value would be?
The piezo sounder is the type with 2 terminals (ground, brass and silver <--> ground, drive, feedback ?).
If the piezo has a resonant driver circuit (I can't tell, but it does use 3 wires) then I think brass is 'drive' and silver is 'feedback'. Or maybe it is simply driven by an H-bridge.
The piezo volume can be somewhat attenuated simply by squeezing between thumb and finger.
Ideally though I would like to be able to smoothly vary the volume. I was wondering whether a simple 'rheostat' in series with ground would work and if so what a sensible value would be?