An S-band 100W GaN Protection Switch

A high-power protection GaN FET switch has been developed. Our invented switching circuit utilizes a new asymmetric series-shunt/shunt configuration. By using the proposed circuit, the power handling capability at isolated state is determined only by the breakdown voltage and the bias voltage of the FETs. So the gate width of the FETs can be determined independently of the power handling capability, and we can overcome the trade-off relationship between the insertion loss at transmission state and the power handling capability at isolated state by using FETs having high breakdown voltage. To verify this methodology, we fabricated the switch with an AlGaN/GaN FET technology, and the circuit achieved the power handling capability of over 100 W, the insertion loss of 0.97 dB, and the isolation of 18.7 dB at 10% bandwidth in S-band.