A full-swing charge pump with zero phase offset

This paper proposes a full-swing charge pump with zero phase offset for charge pump PLL (CP-PLL). The origins of phase offset are discussed and theoretically analyzed. Standard topologies for phase offset improvement are discussed and a new charge pump topology with zero phase offset and full-swing output is presented. Simulation results are presented to show the excellence of charge pump zero phase offset and the large swing of the output voltage.