MULTI-PHASE REALIGNED VOLTAGE-CONTROLLED OSCILLATOR AND PHASE-LOCKED LOOP INCORPORATING THE SAME

摘要

A multi-phase realigned voltage-controlled oscillator (MRVCO) (Figs. 1 and 7) achieves phase realignment (??) based on charge injection (19) in the VCO stages (11, 12, 13) with the injection amount (IALIGN) proportional to the instantaneous phase error between the VCO output clock and a reference clock (CKREF) . The MRVCO may be incorporated as part (117) of an implementation (Figs. 11 and 12) of a multi-phase realigned phase-locked loop (MRPLL) . A separate phase detector (121) , as well as a specific realignment charge pump (123) , may be provided in the PLL for controlling the VCO. The VCO has lower phase modulation noise, so that the PLL has very large equivalent bandwidth.