Gradual frequency changing circuit

Details Gradual frequency changing circuit Gradual frequency changing circuit

1995-03-28

1997-01-07

Wambach, Margaret Rose

Miscellaneous active electrical nonlinear devices, circuits, and

Signal converting, shaping, or generating

Synchronizing

327157, 327160, 327245, H03L 706

Patent

active

055921132

ABSTRACT:
An error-limiting circuit for regulating the time required to bring the output signal of a control system such as a phase-locked loop device into conformance with a reference input signal. For a phase-locked loop system the error-limiting circuit is a phase-error-limiting circuit that provides for a gradual changing of the signal frequency of a voltage-controlled oscillator of the phase-locked loop device so that frequency synchronization of subsequent devices coupled to the phase-locked loop with the reference signal is ensured. The phase-error-limiting circuit forms part of the phase-frequency detector that is coupled to a charge pump that outputs current to a loop filter that in turn effectively controls the voltage-controlled oscillator. The phase-error-limiting circuit acts to assert or de-assert as required an error-correcting UP or DOWN signal to the charge pump. While the charge supplied by the charge pump is normally dependent only on the phase difference between the reference signal and the VCO signal, the phase-error-limiting circuit cuts in to control the UP or DOWN signal duration when the phase difference exceeds some pre-selected value. The phase-error-limiting circuit thereby clips the charge that can be supplied by the charge pump and thereby slows the move of the voltage-controlled oscillator frequency to the reference signal frequency.

REFERENCES:
patent: 5307020 (1994-04-01), Marcuard
patent: 5373255 (1994-12-01), Bray et al.

Affiliated with

Also associated with

Rating

Gradual frequency changing circuit does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Gradual frequency changing circuit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Gradual frequency changing circuit will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1767613