Comparison of different alternatives to drive piezoelectric transformers

Usually, the performance of piezoelectric transformers (PTs) is optimum when they are sinusoidally driven. The PT can also be driven with a quasi-square voltage waveform. Although PT performance is not optimized with a squared driving, corresponding topologies can be simpler and the whole converter can be improved. Those alternatives that keep an interesting trade-off between complexity and PT efficiency are compared, helping to select the best approach for different applications. All the analyzed alternatives are based on the half bridge topology plus an input matching network.