A 0.48mm² Sub-2.4GHz Transceiver with Reused Matching Network and Duty-Cycle Controlled Class-E PA for Medical Band

This paper presents a compact low-power sub-2.4GHz transceiver (TRX) for medical band, consisting of an all-digital phase-locked loop (ADPLL) based transmitter (TX) and a single-path phase tracking receiver (RX). A single-ended duty-cycle controlled class-E power amplifier (PA) with an on-chip harmonic distortion suppression strategy is proposed. The matching network is reused for gate-boosting and noise-canceling in a single-ended low-noise transconductance amplifier (LNTA). This proposed structure needs only two on-chip transformers/inductors as matching networks reducing the silicon area, and embed transmitter/receiver (T/R) switch function without insertion loss. The design of an 8-port transformer makes the layout more compact. The prototype was fabricated in 40-nm CMOS technology, occupying an active silicon area of 0.48 mm². Experimental results show a 2.27mW power consumption with -10dBm output power in TX, The measured 2nd and 3rd harmonic distortion are -52.36dBm and -50.67dBm, respectively. The RX achieves a sensitivity of -93dBm while consuming 2.25mW.