a plurality of multi-phase clocks, each clock of multi-phase clocks having a same frequency but being offset in phase from other clocks in the plurality of multi-phase clocks;

a phase rotator, coupled to the plurality of multi-phase clocks, for selecting a selected clock from the plurality of multi-phase clocks in response to a count value;

an up/down counter, responsive to an increment signal, for increasing or decreasing the count value to the phase rotator;

an output divider, receiving the selected clock from the phase rotator, for generating a phase-modulated output signal that is phase-modulated in response to changes in the count value from the up/down counter;

a feedback divider, receiving a fixed-phase clock having the same frequency as the plurality of multi-phase clocks, for generating a feedback clock;

wherein the up/down counter receives the feedback clock, the up/down counter changing the count value synchronously to the feedback clock;

wherein the fixed-phase clock is one of the plurality of multi-phase clocks permanently selected by the phase rotator for output to the feedback divider; and

a clocked front-end, receiving the feedback clock and an input signal, for generating the increment signal in response to changes of the input signal, wherein the feedback clock synchronizes the clocked front-end,

whereby changes to the input signal cause the phase rotator to select different phase clocks from the plurality of multi-phase clocks to adjust phase of the phase-modulated output signal.