High P1dB and low quiescent current SiGe HBT power amplifier MMIC using self base bias control circuit for 5.8 GHz ETC terminals

A 5.8 GHz high P_1dB and low quiescent current SiGe HBT three-stage power amplifier (PA) MMIC using a self base bias control circuit is described. The self base bias control circuits are applied to the second and the final stage PA´s, and automatically control the base current/voltage according to the output power level. As a result, high P_1dB is obtained at a low quiescent current condition. The simulated results show that the proposed three-stage PA MMIC achieves P_1dB improvement of 1.7 dB compared with a conventional PA using a constant base voltage bias circuit at the same quiescent current condition. The fabricated PA MMIC achieves P_1dB of 15.3 dBm, gain of 19.6 dB with the quiescent current of 22.2 mA at 5.8 GHz.