700W Long Pulse UHF SiC Transistor for Radar Applications

The performance of a 700 Watt SiC SIT device using state of the art silicon carbide technology is described. Operating under pulsed RF conditions of 1mS pulse width, 20% duty cycle, it can deliver 700 Watts peak power at 96 volts. More than 50% efficiency and 8.2 dB gain are attained over the bandwidth of 400-450 MHz. The power density is 1.9 watts/mil. Thermal resistance is 0.19degC/W. The junction temperature remains below 150degC at a flange temperature of 70degC. This combination of high power density and high voltage operation makes these new generation devices ideally suited for new transmitter designs in UHF radar systems.