US4253065A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Clock distribution system for digital computers
Assignee: United States Department of Energy
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Filing: 1978-12-05
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Granted: 1981-02-24
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Expires: 1998-12-05
Abstract
Abstract Apparatus for eliminating, in each clock distribution amplifier of a clock distribution system, sequential pulse catch-up error due to one pulse "overtaking" a prior clock pulse. The apparatus includes timing means to produce a periodic electromagnetic signal with a fundamental frequency having a fundamental frequency component V' 01 (t); an array of N signal characteristic detector means, with detector means No. 1 receiving the timing means signal and producing a change-of-state signal V 1 (t) in response to receipt of a signal above a predetermined threshold; N substantially identical filter means, one filter means being operatively associated with each detector means, for receiving the change-of-state signal V n (t) and producing a modified change-of-state signal V' n (t) (n=1, . . . , N) having a fundamental frequency component that is substantially proportional to V' 01 (t-θ n (t) with a cumulative phase shift θ n (t) having a time derivative that may be made uniformly and arbitrarily small; and with the detector means n+1 (1≦n<N) receiving a modified change-of-state signal V n (t) from filter means no. n and, in response to receipt of such a signal above a predetermined threshold, producing a change-of-state signal V n+1 (t).
Inventors
- 👤 Robert H. Wyman
- 👤 Herschel H. Loomis, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:53
CPC Classifications
H; H03; H03K; H03K5/00; H03K5/125; H03K5/1252
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
245 words
Apparatus for elimination of disabling error due to shift of the trigger voltage thresholds for one or more clock distribution amplifiers in a computer clock distribution system, the apparatus comprising: timing means for producing a periodic electromagnetic signal V' O (t) having a fundamental frequency and a fundamental frequency component V' O1 (t); a linear array of N(≧2) signal characteristic detector means, with the detector means no. 1 receiving the periodic electromagnetic signal from the timing means and producing a change-of-state V 1 (t) in response to receipt of the signal from the timing means that is above a predetermined threshold; N substantially identical filter means, one such filter means being operatively associated with each signal characteristic detector means, for receiving the change-of-state signal V n (t) and producing a modified change-of-state signal V' n (t) having a fundamental frequency component that is substantially proportional to V' O1 (t-θ n (t)), with an associated cumulative phase shift θ n (t) that satisfies |dθ n /dt|<ε, where ε is dependent upon the magnitude of the trigger voltage threshold shift and upon the Q factor of the circuit of the associated filter means, and ε may be made arbitrarily small, independently of n and N, and t; and with the detector means n+1(1≦n<N) receiving a modified change-of-state signal V' n (t) from filter detector means no. n and, in response to receipt of such a signal above a predetermined threshold, producing a change-of-state signal V n+1 (t).
Claim 2
Dependent Claim
245 words
Apparatus for elimination of disabling error due to shift of the trigger voltage thresholds for one or more clock distribution amplifiers in a computer clock distribution system, the apparatus comprising: timing means for producing a periodic electromagnetic signal V' O (t) having a fundamental frequency and a fundamental frequency component V' O1 (t); a linear array of N(≧2) signal characteristic detector means, with the detector means no. 1 receiving the periodic electromagnetic signal from the timing means and producing a change-of-state V 1 (t) in response to receipt of the signal from the timing means that is above a predetermined threshold; N substantially identical filter means, one such filter means being operatively associated with each signal characteristic detector means, for receiving the change-of-state signal V n (t) and producing a modified change-of-state signal V' n (t) having a fundamental frequency component that is substantially proportional to V' O1 (t-θ n (t)), with an associated cumulative phase shift θ n (t) that satisfies |dθ n /dt|<ε, where ε is dependent upon the magnitude of the trigger voltage threshold shift and upon the Q factor of the circuit of the associated filter means, and ε may be made arbitrarily small, independently of n and N, and t; and with the detector means n+1(1≦n<N) receiving a modified change-of-state signal V' n (t) from filter detector means no. n and, in response to receipt of such a signal above a predetermined threshold, producing a change-of-state signal V n+1 (t).
Claim 3
Dependent Claim
16 words
Apparatus according to claim 1, wherein said signal characteristic detector means is a zero crossing detector.
Claim 4
Dependent Claim
15 words
Apparatus according to claim 1, wherein said signal characteristic detector means is a peak detector.
Claim 5
Dependent Claim
27 words
Apparatus according to claim 1, wherein said filter means comprises an inductor, a resistor, and a capacitor arranged in series with said associated signal characteristic detector means.
Claim 6
Dependent Claim
59 words
Apparatus according to claim 1, wherein said filter means comprises a first and a second resistor and an amplifier arranged in series with said signal characteristic detector, a capacitor arranged in parallel with the second resistor and the amplifier, and a capacitor with one terminal grounded and the other terminal electrically connected between the second resistor and the amplifier.
Claim 7
Dependent Claim
26 words
Apparatus according to claim 1, wherein said filter means comprises an electromechanical filter and a resistor arranged in series with said associated signal characteristic detector means.
Claim 8
Dependent Claim
28 words
Apparatus according to claim 1, wherein said filter means is an electromechanical filter and a resistor in parallel, arranged in series with said associated signal characteristic detector means.
Claim 9
Dependent Claim
34 words
Apparatus according to claim 1, wherein said filter means has an associated transfer function with a peak response at a frequency that is substantially identical with said fundamental frequency of said periodic electromagnetic signal.
Claim 10
Dependent Claim
33 words
Apparatus according to claim 1, wherein said filter means has a transfer function with a maximum response at a frequency that is substantially identical with said fundamental frequency of said periodic electromagnetic signal.
Claim 11
Dependent Claim
47 words
Apparatus according to claim 1, wherein said filter means has a transfer function with a maximum response at a frequency that is substantially identical with said fundamental frequency of said filter means, and said filter means is an electromechanical filter and a resistive element, arranged in parallel.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-02-24 | 1984-08-25 | 1985-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-24 | 1988-08-25 | 1989-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-24 | 1992-08-25 | 1993-02-24 | $7700.00 | Window Closed / Lapsed |