On chip 0.5 V 2 GHz four-output quadrature-phase oscillator

In this paper, we present a quadrature-phase oscillator that can provide four output voltages while operating from a single 0.5 V supply. The oscillator is based on two cross-coupled modified differential pair cells and provides signals with a phase difference of ±180° or ±90° depending on the chosen output nodes. A test chip with an active area of 0.175 mm2 was designed and fabricated in a 65-nm CMOS process and its measurement results show a phase noise of −119.5 dBc/Hz at 1 MHz offset from a carrier frequency of 1.967 GHz while consuming 6.15mW. Finally, experimental results show a FoM of 185.5 dB for the core oscillator and a quadrature-phase error of less than ±0.5°. © 2020 Elsevier GmbH