#596 OpAmp Piezo Driver
Testing a circuit for driving a piezoelectric transducer for sound output with a TL072 opamp oscillator.
As discussed in LEAP#455 Piezo Transducers and Buzzers, piezoelectric transducer require an external oscillator to produce sound.
This is an example of an OpAmp driver:
- comparator-based relaxation oscillator implemented with one OpAmp from a TL072
- 2N7000 switch to enable the oscillator
- driving a passive buzzer element
NB: I have seen silimar circuits with an NPN BJT switch but some of these don’t seem to turn the oscillator hard enough off.
Works fine - emits a constant tone when the button is pressed.
A crude estimate just considering the 20kΩ and 10nF RC path suggest a frequncy ~796 Hz. Actually 844Hz acording to the scope..