Method for managing a phase-locked loop and related circuit
AssigneeSTMicroeletronics (Rousset) SAS
InventorBruno Gailhard
Life of this patent
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Abstract
A method can be used for managing the operation of a phase-locked loop. The loop includes an oscillator voltage controlled by a control signal and a phase comparator receiving a reference signal and a feedback signal which arises from the output signal of the oscillator. The method includes a detection of a possible absence of transitions on the feedback signal for a first duration and, in response to such an absence, a forcing of the lowering of the voltage of the control signal at least until a reappearance of transitions on the feedback signal.
Claims21
A method for managing the operation of a phase-locked loop that comprises an oscillator that is controlled by a voltage of a control signal and a phase comparator that receives a reference signal and a feedback signal that arises from an output signal of the oscillator, the method comprising:
- detecting an absence of transitions on the feedback signal for a first duration;
- and
- in response to the absence of transitions, forcing the voltage of the control signal to be lowered at least until a reappearance of transitions on the feedback signal.
An integrated circuit comprising:
- a phase-locked loop comprising an oscillator configured to be controlled by a voltage a control signal;
- a phase comparator configured to receive a reference signal and a feedback signal that arises from an output signal of the oscillator;
- a detector configured to detect an absence of transitions on the feedback signal for a first duration;
- and
- a controller configured to force the voltage of the control signal to be lowered in response to the absence of transitions on the feedback signal at least until a reappearance of transitions on the feedback signal.
An integrated circuit comprising:
- a phase-locked loop comprising an oscillator configured to be controlled by a voltage a control signal;
- a phase comparator configured to receive a reference signal and a feedback signal that arises from an output signal of the oscillator;
- a detector configured to detect an absence of transitions on the feedback signal for a first duration, the detector comprising a first counter configured to count pulses of the reference signal until attaining a first counting value corresponding to the first duration;
- and
- a controller configured to force the voltage of the control signal to be lowered in response to the absence of transitions on the feedback signal, the control signal being lowered until expiration of a second duration after a reappearance of transitions on the feedback signal.
Dependencies are inferred from the claim text.