Oscillators – Automatic frequency stabilization using a phase or frequency... – Plural oscillators controlled
Reexamination Certificate
2006-11-21
2006-11-21
Callahan, Timothy P. (Department: 2816)
Oscillators
Automatic frequency stabilization using a phase or frequency...
Plural oscillators controlled
C331S056000
Reexamination Certificate
active
07138877
ABSTRACT:
A PLL circuit and method provides an adjustable operating frequency range by using at least two VCOs. In an embodiment of the present invention, circuit components of a PLL are adjusted in order to obtain a selected frequency range. In particular, a gain of a charge pump and resistance of a filter is adjusted responsive to a control signal. In alternate embodiments of the present invention, a voltage regulator, including an operational amplifier, is coupled to the output of the filter and the respective inputs of two VCOs. An output multiplexer then selects a VCO output responsive to the control signal. In another embodiment of the present invention, a multiplexer is coupled to the output of the voltage regulator to select which VCO receives a buffered voltage. In another embodiment of the present invention, respective operational amplifiers that may be enabled or disabled responsive to the control signal are coupled to a filter output and respective VCO inputs in order to provide an adjustable frequency range.
REFERENCES:
patent: 5389898 (1995-02-01), Taketoshi et al.
patent: 5742798 (1998-04-01), Goldrian
patent: 6031426 (2000-02-01), Yechuri
patent: 6188285 (2001-02-01), Nakanishi et al.
patent: 6304146 (2001-10-01), Welland
patent: 6650141 (2003-11-01), Agrawal et al.
patent: 6785525 (2004-08-01), Ries
patent: 6788155 (2004-09-01), Chaudhuri et al.
patent: 6954091 (2005-10-01), Wurzer
patent: 2003/0137328 (2003-07-01), Kurd et al.
patent: 02000035831 (2000-02-01), None
Lau Benedict
Nguyen Huy
Vu Roxanne
Callahan Timothy P.
Cox Cassandra
Rambus Inc.
Vierra Magen Marcus & DeNiro LLP
LandOfFree
PLL and method for providing a single/multiple adjustable... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with PLL and method for providing a single/multiple adjustable..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and PLL and method for providing a single/multiple adjustable... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3671231