(A) low-power RSSI and reconfigurable LNA design for human body communication

Abstract

A low-power duty controlled received signal strength indicator (RSSI) is implemented for human body communication (HBC) in 0.18-$\mu$m CMOS technology with 1.5-V supply. It has 3 key features

1) current reusing RSSI (CR-RSSI) with replica bias circuit and calibration unit, 2) duty controller and 3) reconfigurable gm-boosting LNA. The CR-RSSI utilizes amplifier-rectifier-cell (AR-cell) to reduce the power consumption of RSSI to only 540-$\mu$W with 1.7-dB accuracy in 80-dB dynamic range. Replica bias circuit and calibration unit are integrated with AR-cell to improve reliability of CR-RSSI. To further reduce the power consumption, duty controller and reconfigurable gm-boosting LNA (Low noise amplifier) are adopted. CR-RSSI can save 55% of power compared to the previous work, and duty controller can reduce 70% of average power. Ac-cording to input signal strength, the reconfigurable gm-boosting LNA is adaptively configured to save 62% of LNA power consumption. As a results, 70% of total power can be saved compared to the previous work. This work is the lowest power consuming RSSI with wide input dynamic range.