A Compact 915-MHz 0.6-V Transceiver With 23.3-nW Standby Power and Parallel Data Serialization TX for Biomedical Applications

This article presents a compact, low-power radio frequency (RF) transceiver (TRX) with 0.6 V supply for implantable body-area health monitoring applications. An asymmetric TRX is proposed to meet the distinct requirements of doctor–patient communication, characterized by continuous standby operation and burst-mode data transmission upon request. The relationship between data rate (DR) and sensitivity in the envelope-detector-first (ED-first) receiver (RX) is analytically derived. The RX operating at 1 kb/s with −65 dBm sensitivity is implemented, consuming only 23.3 nW. The TRX incorporates a reconfigurable <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\pi $</tex-math> </inline-formula>-type matching network (MN), shared between the transmitter (TX) and RX through by switching capacitors, eliminating the need for a duplexer and enabling antenna reuse. The TX supports 8-bit parallel data serialization by time-multiplexing the frequency-locked loop (FLL), which matches the parallel data characteristics in health monitoring applications. Supporting both OOK and FSK modulation modes, the TX achieves a DR of 1 Mb/s with a peak power consumption of 1.15 mW at −10 dBm output power, resulting in an energy efficiency of 1.15 nJ/bit. Fabricated in 65-nm complementary metal-oxide-semiconductor (CMOS) process, the core area of the TRX is 0.305 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>.