The SA08 and SA18 hybrid PWM amplifiers are full H-bridge and half-bridge devices, respectively, and both provide 20A of output current for a total power delivery of 10 kW to the load. The 500V amplifiers run from a wide single supply of 16V to 500V, which enables them to be designed into applications without transformers, where the wall outlet voltages range from 115 vac to 230 vac. In these amplifiers, an IGBT output stage provides lower voltage drop (2.7V at 20A) and higher efficiency (98%) than their sister models SA06 and SA16. The IGBTs on the output stage are protected from thermal overloads by directly sensing the die temperature.A 22.5-kHz switching frequency on both models is provided by a clock input stage that divides an internal oscillator frequency by two. No external components are required on the oscillator, which also can be used for synchronizing multiple amplifiers. Both units come in a 12-pin hermetic MO-127 power package.