I am trying to build an array of ultrasonic sensors for haptic feedback in mid air. The haptic feedback is achieved by suppling the ultrasonisc sensors with a rectangular voltage of 40kHz and a superimpossed lower frequency of about 100-400Hz. My question now is how to best drive the single sensors.
I already read this thread that talks about ultrasonic driving ciurcuits.
Most links suggest to use a H-Bridge to drive a sensor. With an array of let's say 4x4 sensors however, several H-Bridges would be necessary. I wonder if it's possible to just use one transistor (e.g. 2N2222) for each sensor to amplify Arduino's PWM output to about 20V. A decoupling capacitor would then filter the DC and supply an alternating rectangular voltage to each sensor. Would that work?