A Mixer-First Receiver With Class-F Adiabatic Switching

This letter introduces the use of
class-
F adiabatic
switching
in a mixer-first 2.45-GHz ISM-band receiver. By using the principle of adiabatic switching with a class-F VCO, a resonant multiharmonic drive for an N-path-based mixer-first receiver is generated, resulting in a reduced power consumption while maintaining a good mixer noise figure (NF). To optimize the area, coupled inductors in the VCO are used. By employing a switched capacitor (SC) feedback network in the baseband (BB) amplifier, a proper input matching and flexible common-mode (CM) bias is achieved. A packaged chip implemented in 28-nm CMOS achieves a low-power consumption of 3.5 mW with a gain of 22 dB and an NF of 7.4 dB.