A 2.4-GHz Single-Pin Antenna Interface RF Front-End with a Function-Reuse Single-MOS VCO-PA and a Push-Pull LNA

We propose a power-efficient sub-1V RF front-end (RFE) for 2.4GHz transceivers. It introduces the following innovations: 1) function-reuse single-MOS VCO-PA with full VDD utilization while improving antenna-to-VCO isolation for better resilience to jammers; 2) a non-inverting transformer with a zero-shifting capacitor that suppresses the 2nd harmonic emission of the VCO-PA, and allows a single-pin antenna interface for both TX and RX modes; and 3) a push-pull LNA with passive gain boosting that reduces power consumption. Fabricated in 65nm CMOS, the RFE occupies merely 0.17mm2. By scaling the supply voltage, the standalone VCO-PA exhibits a 20.8% (10.2%) power efficiency when delivering 0dBm (-10dBm) output. The LNA shows 11dB gain and 6.8dB NF while consuming 174μW.