US3617855A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Phase-detecting circuits
Assignee: NIPPON OCEANICS INST Ltd
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Filing: 1970-09-23
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Granted: 1971-11-02
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Expires: 1990-09-23
Abstract
Abstract A circuit for detecting the phase of an AC input signal comprises first and second differential amplifiers connected in parallel, means to render the first and second differential amplifiers ON and OFF with a phase difference of 180* in response to the AC input signal, and a third differential amplifier which compares outputs from the first and second differential amplifiers to provide a DC output having a polarity related to the phase of the AC input signal.
Inventors
- 👤 Chosaku Hisatsu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:15
CPC Classifications
G; G01; G01R; G01R25/00
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
77 words
A phase-detecting circuit comprising a first differential amplifier, a second differential amplifier connected in parallel with said first differential amplifier, means to render said first and second differential amplifiers ON and OFF with a phase difference of 180* in response to an AC input signal, and a third differential amplifier which compares outputs from said first and second differential amplifiers to provide a DC output having a polarity related to the phase of said AC input signal.
Claim 2
Dependent Claim
77 words
A phase-detecting circuit comprising a first differential amplifier, a second differential amplifier connected in parallel with said first differential amplifier, means to render said first and second differential amplifiers ON and OFF with a phase difference of 180* in response to an AC input signal, and a third differential amplifier which compares outputs from said first and second differential amplifiers to provide a DC output having a polarity related to the phase of said AC input signal.
Claim 3
Dependent Claim
124 words
A phase-detecting circuit comprising first and second differential amplifiers connected in parallel; each of said differential amplifiers including parallely connected first and second transistors and a transistor connected in series with said first and second transistors; means to impress an AC input signal upon the first transistor of each differential amplifier; means to impress a reference voltage upon the second transistor of each differential transistor; means to impress AC reference voltages of the opposite phase upon the third transistor of said first and second differential amplifier; and a third differential amplifier including parallel connected transistors respectively responsive to the outputs from said first and second differential amplifiers to produce a DC output having a polarity related to the phase of said input AC signal.
Claim 4
Dependent Claim
124 words
A phase-detecting circuit comprising first and second differential amplifiers connected in parallel; each of said differential amplifiers including parallely connected first and second transistors and a transistor connected in series with said first and second transistors; means to impress an AC input signal upon the first transistor of each differential amplifier; means to impress a reference voltage upon the second transistor of each differential transistor; means to impress AC reference voltages of the opposite phase upon the third transistor of said first and second differential amplifier; and a third differential amplifier including parallel connected transistors respectively responsive to the outputs from said first and second differential amplifiers to produce a DC output having a polarity related to the phase of said input AC signal.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-01 | 1975-05-03 | 1975-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-01 | 1979-05-03 | 1979-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-01 | 1983-05-03 | 1983-11-02 | $7700.00 | Window Closed / Lapsed |