A 0.65V CMOS Power Amplifier for Biotelemetry Applications

In order to reduce the power consumption in biomedical implantable electronic systems, there is a major demand on reducing the supply voltage. This paper presents a fully integrated, 650 MHz class-E power amplifier (PA), with a class-F driver stage that is suitable for low-voltage operation. The circuit was fabricated in a standard $0.18\ \mu m$ CMOS technology. Measurement results show a maximum drain efficiency of 15% and a maximum gain of 11.5 dB. When operated from a 0.65 V supply, the PA delivers an output power of $750\ \mu W$ with a maximum power-added efficiency (PAE) of 10%. The circuit also has a second output to test the effects of using an on-chip filter in low-power designs. This work demonstrates the feasibility of using class-E PAs for short-range, low-power applications.