A 2.5 watt X-band high efficiency MMIC amplifier

A broadband two-stage X-band high-efficiency power amplifier using ion-implanted MMIC (monolithic microwave IC) technology is presented. The amplifier has 2.3-W to 2.9-W CW output power, 31% to 35% power-added efficiency, and 11-dB power gain across the frequency band. These data represent state-of-the-art performance for an MMIC amplifier. The amplifier design utilizes the waveform-balance nonlinear CAD. The optimum load impedances of the FETs for power matching are first generated by computer. These data are then used to optimize the matching circuits. The circuit is fabricated by the standard Hughes 0.5- mu m ion-implantation MMIC process. The doping profile is optimized for high breakdown voltage and transconductance. The amplifier is a true monolithic circuit since it does not use any offchip combining or tuning. >