SINGLE 1.5 V OPERATION POWER-AMPLIFIER MMIC WITH SRTIO3 CAPACITORS FOR 2.4 GHZ WIRELESS APPLICATIONS

This paper describes design approach and power performance of a single 1.5 V operation two-stage power amplifier MMIC for 2.4 GHz wireless l ocal area network applications. The MMIC with 0.76 x 0.96 mm(2) area i ncludes SrTiO3 (STO) capacitors with a high capacitance density of 8.0 fF/mu m(2) and double-doped AlGaAs/InGaAs/AlGaAs heterojunction FETs with a shallow threshold voltage of - 0.24 V. Utilizing a series STO c apacitor and a shunt inductor as an output matching circuit, the total chip size was reduced by 40% as compared with an MMIC utilizing SiNx capacitors. Under single 1.5 V operation, the developed MMIC delivered an output power of 110 mW (20.4 dBm) and a power-added efficiency (PA E) of 36.7% with an associated gain of 20.0 dB at 2.4 GHz. Even operat ed at a drain bias voltage of 0.8 V, the MMIC exhibited a high PAE of 31.0%.