Optical I/O core based on silicon photonics technology and optical/electrical assembly was developed as a fingertip-size optical module with high bandwidth density, low power consumption, and high temperature operation. The advantages of the optical I/O core, including hybrid integration of quantum dot laser diode and optical pin, allow us to achieve 300-m transmission at 25Gbps per channel when optical I/O core is mounted around field-programmable gate array without clock data recovery.

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 local area network applications. The MMIC with 0. 760. 96 mm2 area includes SrTiO3 (STO) capacitors with a high capacitance density of 8. 0 fF/µm2 and double-doped AlGaAs/InGaAs/AlGaAs heterojunction FETs with a shallow threshold voltage of -0. 24 V. Utilizing a series STO capacitor 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 (PAE) of 36.7% with an associated gain of 20.0 dB at 2.4 GHz. Even operated at a drain bias voltage of 0.8 V, the MMIC exhibited a high PAE of 31.0%.