INTEGRATED CIRCUIT PHASE-LOCKED LOOP CHARGE PUMP

摘要

A charge pump (2) is supplied to reset in rated conditions the error signal of a phase-locked loop of the type whereby a phase detector (1) periodically supplies this pump (2) with a first and second impulse having emission instants dependent on the phase ratio between phase-locked loop input signals and are allocated to control circuit output increase or decrease respectively by means of ring filter (3a, 3b). The pump features loops (21, 22, 23, 24, 28) to transform the first and second impulse into a first and second voltage signal of longer duration than maximum impulse duration and featuring values the difference of which depends on the phase ratio between the loop input signals and to generate a signal in a current representative of such difference.