The UES704 series of ultrafast high-efficiency rectifiers is specifically designed for operation in power switching circuits operating at frequencies of 20 kHz or higher. The low thermal resistance and forward voltage drop of this series allows the user to replace DO-5 size devices in many applications. These devices have also been demonstrated capability in passing power-stress testing to 25 thousand cycles with full-rated forward current turned on and off without a heat sink. This forces case temperature increases of 75°C at which time the current is removed to simulate worst case applications. The switching times increase relatively little with temperature or at different currents.