PHASE CONTROL CIRCUIT.

摘要

A phase control circuit for controlling the relative phase of periodic components of two logic signals having the same frequency, and one of which periodic components has a pulse-duty factor different from 50:50, said circuit includes a signal source which provides a control signal for regulating the relative phase of the periodic components of said logic signals. The control signal has a first value for phase relationships in a predetermined range of values and a second value for phase relationships outside said range of values. A phase lock detector detects the lock status of the periodic components of the logic signals. Another signal source provides a third logic signal having a periodic component having the same frequency as the periodic component of each of the two logic signals and a pulse width substantially wider than that of the two logic signals. A switch is actuated by the phase lock detector and applies the third logic signal to the signal source when the two logic signals are out-of-lock whereby the control signal has the first value when the two logic signals are phase locked and the second value when the two logic signal are not phase locked.