Hi Wayne, The DRV2700EVM can drive up to 100Vp, 200Vpp - differentially, across the outputs. The DRV2700EVM-HV500 can drive up to 500Vp on a single ended output. For each EVM, the output capacitance will directly effect the output bandwidth. The bandwidth is also dependent on the boost voltage. This is shown in figures 9-12 of the datasheet. Reference figure 12: boost = 105V; max frequency for a 1uF load is ~30Hz. For a 30uF load, the boost voltage of the DRV2700 will most likely sag or decrease when the output is activated. This is because the part cannot source enough current to charge the large capacitive load. After some time (>1s), the load will be charged to 100V. When you switch to charge the OUT- terminal, the boost will again decrease as the part fights to charge the load. So can the piezo be driven, yes; but only at a frequency less than 1Hz. You would see similar effects on the DRV2700EVM-500HV with the 4*3.7uF load. These parts were not designed to drive such high capacitive loads.
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