I am designing a circuit to excite a piezo-electric crystal with 1MHz bipolar square wave at 30V (Vp-p=30V, Vb-p=15V) consisting of 10 pulses, 50% duty cycle.
The idea is to use a pulse transformer whose inputs shall be driven with +15V from either directions to achieve bipolar excitation. First, IN_A will be driven with +15V while IN_B is at ground and vice versa.
1) The voltage * time product in this case should be 15V * (1/1MHz) = 15V-us. Is this correct?
2) Or should it be 30V * (1/1MHz) = 30V-us since the excitation is bipolar?
3) Finally, since the excitation consists of 10 pulses and not just a single pulse, should the calculation of V * t value take that into account as well?