Digital voltage controlled oscillator
First Claim
1. A digital phase lock loop, comprising:
- a digital voltage controlled oscillator which is responsive to a first set of control signals to provide an output signal;
a phase detector for receiving and comparing the frequency of said output signal with the frequency of a reference signal, and for outputting a second control signal based on the comparison; and
a digital filter which is responsive to said second control signal to output said first set of control signals to said digital voltage controlled oscillator, said digital voltage controlled oscillator comprising (i) an array of delay elements and (ii) a decoder for receiving said first set of said control signals and selectively activating one or more of said delay elements in response thereto.
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Accused Products
Abstract
A digital phase lock loop is provided, comprising a digital voltage controlled oscillator, a phase detector, and an up/down counter. The digital voltage controlled oscillator is responsive to a first set of control signals received from the up/down counter to provide an output signal. The phase detector receives and compares the frequency of the output signal with the frequency of a reference signal and, based on the comparison, outputs to the up/down counter a second control signal which determines the status of the first set of control signals. The digital voltage controlled oscillator comprises (i) an array of delay elements and (ii) a decoder for receiving the first set of the control signals from the up/down counter and for selectively activating one or more of the delay elements in response thereto. The decoder provides a separate output line for each of the delay elements which is to be selectively activated. The logic required to implement the decoder requires only a single AND gate and a single OR gate for each of the delay elements in the array.
53 Citations
17 Claims
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1. A digital phase lock loop, comprising:
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a digital voltage controlled oscillator which is responsive to a first set of control signals to provide an output signal; a phase detector for receiving and comparing the frequency of said output signal with the frequency of a reference signal, and for outputting a second control signal based on the comparison; and a digital filter which is responsive to said second control signal to output said first set of control signals to said digital voltage controlled oscillator, said digital voltage controlled oscillator comprising (i) an array of delay elements and (ii) a decoder for receiving said first set of said control signals and selectively activating one or more of said delay elements in response thereto. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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10. A digital voltage controlled oscillator for use in a digital phase lock loop comprising:
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(i) an array of delay elements arranged in a matrix of rows and columns, and (ii) a decoder for receiving said first control signal and selectively activating one or more of said delay elements in said array in response thereto. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17)
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Specification