Edge transition insensitive delay line system and method
First Claim
1. A system for recovering a clock signal from a data signal having rising and falling data transitions, comprising:
- detection means for detecting data transitions in the data signal;
transition means for generating a transition signal indicative of a detected data transition, wherein the transition signal has a logic level associated therewith and wherein the logic level is a first level when a transition is detected;
delay means for delaying the transition signal by a preselected time period;
means responsive to a correction signal for generating a clock signal having clock transitions which occur in synchronization with the data transitions;
comparison means for comparing the delayed transition signal to a reference signal and for generating the correction signal indicative of a phase difference therebetween; and
gating means responsive to the first logic level of the transition signal for supplying the clock signal to the comparison means such that the clock signal is the reference signal.
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Accused Products
Abstract
A system (100, 50, 300) for recovering a clock signal from a serial data signal (102) having rising (204) and falling (206) transitions. The transistions (204, 206) are detected by a transition detector (11, 12, 108, 110) which generates a transition signal (13a, 13b, 109, 111) having a first logic state when a rising (204) or falling (206) transition is detected. The system (100, 50, 300) includes a delay device (22, 120, 122) which delays the transition signal (13a, 13b, 109, 111) by a preselected time period and a gating device (24, 124, 126) responsive to the transition signal (13a, 13b, 109, 111). The gating device (24, 124, 126) is enabled by the transition signal (13a, 13b, 109, 111) when the signal is the first logic state, thereby permitting a system generated clock signal (148) to propagate to a phase comparison system (132, 134, 176, 178, G 1, G4) for comparison with the delayed transition signal (23, 128, 130). The phase comparison system (132, 134, 178, G1, G4) generate a correction signal (30) indicative of the phase difference between the compared signals (23, 25, 144, 152, 130, 154) such that the transitions in clock signal (148) generated are in synchronization with the data transitions (204, 206).
99 Citations
24 Claims
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1. A system for recovering a clock signal from a data signal having rising and falling data transitions, comprising:
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detection means for detecting data transitions in the data signal; transition means for generating a transition signal indicative of a detected data transition, wherein the transition signal has a logic level associated therewith and wherein the logic level is a first level when a transition is detected; delay means for delaying the transition signal by a preselected time period; means responsive to a correction signal for generating a clock signal having clock transitions which occur in synchronization with the data transitions; comparison means for comparing the delayed transition signal to a reference signal and for generating the correction signal indicative of a phase difference therebetween; and gating means responsive to the first logic level of the transition signal for supplying the clock signal to the comparison means such that the clock signal is the reference signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
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15. A system for regenerating a clock signal from a data signal having rising and falling data transitions, comprising:
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rising detecting means for detecting a rising data transition in the data signal; negative detecting means for detecting a falling data transition in the data signal; rising transition means for generating a rising transition signal indicative of the detected rising transition, wherein the rising transition signal has a logic level associated therewith wherein the logic level is a preselected level when a rising transition is detected; falling transition means for generating a falling transition signal indicative of the detected falling data transition in the data signal, wherein the falling transition signal has a logic level associated therewith wherein the logic level is the preselected level when a falling transition is detected; delay means for delaying the data signal by a preselected time period; means responsive to a correction signal for generating a clock signal having clock transitions which occur in synchronization with the data transitions; comparison means for comparing the delayed data signal to a reference signal and for generating the correction signal indicative of a phase difference therebetween; and gating means responsive to the rising transition signal and the falling transition signal for supplying the clock signal to the comparison means when a transition is detected such that the clock signal is the reference signal. - View Dependent Claims (16)
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17. A method for recovering a clock signal from a data signal having rising and falling data transitions, comprising:
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detecting a data transitions in the data signal; generating a transition signal indicative of a detected transition, wherein the transition signal has a logic level associated therewith and wherein the logic level is a first preselected level when a transition is detected; delaying the transition signal by a preselected time period; generating a clock signal having clock transitions which occur in synchronization with the data transitions in response to a correction signal; comparing in a means for comparing the delayed transition signal to a reference signal and generating the correction signal indicative of a phase difference therebetween; and supplying the clock signal to the means for comparing in response to the first logic level of the transition signal such that the clock signal is the reference signal. - View Dependent Claims (18, 19, 20, 21)
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22. A system for recovering a clock signal from a data signal having logic state transitions, the system comprising:
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detection means for detecting logic state transitions in the data signal; transition means for generating a transition signal indicative of a detected logic state transition; delay means for delaying the transition signal by a preselected time period; means responsive to a correction signal for generating a clock signal having clock transitions which occur in synchronization with the logic state transitions; comparison means for comparing the delayed transition signal to a reference signal and for generating the correction signal indicative of a phase difference between the reference signal and the delayed transition signal; and gating means responsive to the transition signal for supplying the clock signal to the comparison means such that the clock signal is the reference signal. - View Dependent Claims (23)
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24. A system for regenerating a clock signal from a data signal having logic state transitions, the system comprising:
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first detection means for detecting a first logic state transition in the data signal; second detection means for detecting a second logic state transition in the data signal; first transition means for generating a first transition signal when a first logic state transition is detected; second transition means for generating a second logic state transition signal when a second logic state transition is detected; first delay means for delaying the first transition signal by a preselected time period; second delay means for delaying the second transition signal by the preselected time period; first comparison means for comparing the delayed first transition signal to a reference signal and for generating a first correction signal indicative of a phase difference between the delayed first transition signal and the reference signal; second comparison means for comparing the delayed second transition signal to the reference signal and for generating a second correction signal indicative of a phase difference between the delayed second transition signal and the reference signal; means responsive to the first correction signal and the second correction signal for generating a clock signal having clock transitions which occur in synchronization with the detected first and second logic state transition; first gating means for supplying the clock signal to the first comparison means when a first logic transition is detected; and second gating means for supplying the clock signal to the second comparison means when a second logic transition is detected.
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Specification