I have been working on a pulse generator circuit which will be used to drive an ultrasonic probe. In the circuit below, the 50Ω resistor is modeling the probe.
I have researched the piezoelectric effect, but different sources explain it in different ways. Some have said that they are activated by current, and others have said they are activated by AC.
Since I am using DC voltage pulses to control the transducer, I am wondering if this will operate as I require. PSPICE outputs the following graph for the circuit shown above, measured from the node above 50Ω resistor.
Am I correct in thinking that the piezoelectric crystals in the probe would only generate ultrasound during the change in voltage? Or would there be some ultrasound emitted during the high of 220V as well?