A 2.2GHz 7.6mW Sub-Sampling PLL with -126dBc/Hz In-band Phase Noise and 0.15psrms Jitter in 0.18μm CMOS

A clock with low phase-noise/jitter is a prerequisite for high-performance ADCs, wireline and optical data links and radio transceivers. This paper presents a 2.2GHz clock-generation PLL. It uses a phase-detector/charge-pump (PD/CP) that sub-samples the VCO output with the reference clock. The PLL does not need frequency divider in locked state and achieves a low in-band phase noise values at low power