The actuator's vibration strength is proportional to the driving signal. Therefore, the supply voltage sets a limit for maximum vibrations on a particular system. For LRA actuators in particular, a differential output is recommended in order to maximize the vibration strength. If using a typical Li-Ion battery, a single ended solution (such as that obtained by a single FET implementation) will be limited to the voltage of the battery, which will make waveforms such as the one shown in Figure 3-1 not possible to obtain.