Multi-Stage GaN Power Amplifier Reference Design - Delivering 150 W for 3.1-3.5 GHz S-Band Radar

Wolfspeed has developed a three-stage application circuit demonstrator using two Cree 50 volt GaN products. The two products are a QFN 2 stage plastic MMIC used as a driver and an input matched metal ceramic packaged HEMT transistor, CMPA2735015S and CGHV35120F respectively. The purpose of this application circuit is to demonstrate Wolfspeed GaN HEMT technology capabilities with respect to harmonic content, power added efficiency (PAE), size weight and power (SWaP). The prototype was evaluated using a 10% duty cycle pulsed single tone signal with a 100us pulse width. This whitepaper describes the typical performance that has been achieved and that which can be expected when evaluating the demonstrator. Details of the circuit are included for further understanding of the topology.