A sonotrode for an ultrasound welding device including at least one working surface and a front surface that extends perpendicularly to the working surface. The solid state energy conversion device comprises a wide bandgap semiconductor material having a first doped region. The optical gain control unit is configured to control the gain of the optical output signal. The Schottky bridge provides an open circuit arrangement between the TIA circuit and a current source when the overdrive condition occurs. The method includes applying a composite pulse including a direct current pulse and a DC perturbation pulse to the nonvolatile memory device to perform the erase operation.