A 1–5 GHz 22 mW receiver frontend with active-feedback baseband and voltage-commutating mixers in 65 nm CMOS

A CMOS baseband-active-feedback receiver frontend with passive voltage-commutating mixers is proposed. The active feedback baseband enables in-band signal amplification and out-of-band blocker interference suppression by constructing the RF bandpass filter and BB lowpass filter, simultaneously. The voltage-commutating mixers embedded in current mirrors significantly reduce the power requirement for the LO generator. The stacked n/pMOS structure is commonly adopted to further improve power efficiency. The receiver frontend is designed in a standard 65 nm CMOS process. Simulation results display an NF of 3.4 dB and a maximum gain of 32 dB from 1 to 5 GHz LO frequency range. The obtained in-band and out-of-band IIP3 are −12 dBm and 9 dBm, respectively. The receiver frontend core only consumes 22 mW at 1 GHz LO frequency and occupies the area of 645 × 543 μm², which is suitable for the low-power application of handheld terminals.