Bipolar bandwidth switch for use in a phase-locked loop

Details Bipolar bandwidth switch for use in a phase-locked loop Bipolar bandwidth switch for use in a phase-locked loop

1987-03-06

1987-11-03

LaRoche, Eugene R.

Oscillators

Automatic frequency stabilization using a phase or frequency...

With reference oscillator or source

331 8, 331 34, H03L 710

Patent

active

047045868

ABSTRACT:
An integrated circuit phase-locked loop includes a bipolar bandwidth switch for selectively coupling circuit elements of an external bandwidth filter network so as to control loop bandwidth. The bandwidth switch includes first and second switched terminal means which are coupled to the bandwidth filter network. A differential amplifier has a first control terminal coupled to the first switched terminal and a second control terminal coupled to the second switched terminal. The differential amplifier controls first and second currents as a function of a difference between potentials applied to the first and second switched terminals. A first current mirror couples the differential amplifier to the second switched terminal and controls current flow between a first supply terminal and the second switched terminal as a function of the first current. A second current mirror couples the differential amplifier to the second switched terminal and controls current flow between the second switched terminal and a second supply terminal as a function of the second current. Control means responsive to digital control signals control current flow through the differential amplifier, and thereby the impedance between the first and second switched terminals.

REFERENCES:
patent: 4516083 (1985-05-01), Turney
patent: 5410461 (1985-04-01), Dickes et al.

Affiliated with

Also associated with

Rating

Bipolar bandwidth switch for use in a phase-locked loop does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Bipolar bandwidth switch for use in a phase-locked loop, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bipolar bandwidth switch for use in a phase-locked loop will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1675976