Patent US3275945A successfully refreshed from Google Patents.
US3275945A
Expired / Lapsed
US
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Direct coupled differential amplifier with common mode rejection
Assignee: RACAL-DANA INSTRUMENTS Inc
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Filing: 1963-06-04
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Granted: 1966-09-27
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Expires: 1983-06-04
Abstract
No abstract record available.
Inventors
- 👤 Norman C Walker
- 👤 Charles E Engle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:53
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/45; H03F3/45071; H03F3/45479
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
151 words
A DIRECT COUPLED DIFFERENTIAL AMPLIFIER HAVING A PAIR OF AMPLIFIER INPUT TERMINALS AND A COMMON BUS AND COMPRISING: A DUAL TRANSISTOR INPUT STAGE INCLUDING TWO SUBSTANTIALLY SYMMETRICALLY INTERCOUPLED TRANSISTORS EACH HAVING AN INPUT ELECTRODE COUPLED TO A RESPECTIVE ONE OF SAID AMPLIFIER INPUT TERMINALS AND BEING OF THE CHARACTER SENSITIVE TO DIFFERENTIAL SIGNALS ON SAID AMPLIFIER INPUT TERMINALS FOR PROVIDING OUTPUT SIGNALS REPRESENTATIVE THEREOF; A COMMON MODE SIGNAL DETECTOR AND AMPLIFIFER COUPLED TO SAID INPUT STAGE AND BEING RESPONSIVE TO COMMON MODE SIGNALS ON SAID INPUT TERMINALS TO GENERATE A NEGATIVE FEEDBACK SIGNAL AND TO IMPRESS IT UPON A CIRCUIT POINT INTERCOUPLED ELECTRICALLY BETWEEN AND EQUIDISTANT FROM A LIKE ELECTRODE OF EACH OF SAID TRANSISTORS; AND INDUCTIVE WINDING INTERCOUPLED BETWEEN EACH SAID INPUT ELECTRODE OF SAID DUAL TRANSISTORS AND A RESPECTIVE ONE OF SAID INPUT TERMINALS; AND A FILTER CAPACITOR INTERCOUPLED BETWEEN EACH OF SAID INDUCTIVE WINDINGS AND SAID CIRCUIT POINT.
Claim 2
Dependent Claim
151 words
A DIRECT COUPLED DIFFERENTIAL AMPLIFIER HAVING A PAIR OF AMPLIFIER INPUT TERMINALS AND A COMMON BUS AND COMPRISING: A DUAL TRANSISTOR INPUT STAGE INCLUDING TWO SUBSTANTIALLY SYMMETRICALLY INTERCOUPLED TRANSISTORS EACH HAVING AN INPUT ELECTRODE COUPLED TO A RESPECTIVE ONE OF SAID AMPLIFIER INPUT TERMINALS AND BEING OF THE CHARACTER SENSITIVE TO DIFFERENTIAL SIGNALS ON SAID AMPLIFIER INPUT TERMINALS FOR PROVIDING OUTPUT SIGNALS REPRESENTATIVE THEREOF; A COMMON MODE SIGNAL DETECTOR AND AMPLIFIFER COUPLED TO SAID INPUT STAGE AND BEING RESPONSIVE TO COMMON MODE SIGNALS ON SAID INPUT TERMINALS TO GENERATE A NEGATIVE FEEDBACK SIGNAL AND TO IMPRESS IT UPON A CIRCUIT POINT INTERCOUPLED ELECTRICALLY BETWEEN AND EQUIDISTANT FROM A LIKE ELECTRODE OF EACH OF SAID TRANSISTORS; AND INDUCTIVE WINDING INTERCOUPLED BETWEEN EACH SAID INPUT ELECTRODE OF SAID DUAL TRANSISTORS AND A RESPECTIVE ONE OF SAID INPUT TERMINALS; AND A FILTER CAPACITOR INTERCOUPLED BETWEEN EACH OF SAID INDUCTIVE WINDINGS AND SAID CIRCUIT POINT.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-09-26 | 1970-03-28 | 1970-09-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-09-26 | 1974-03-28 | 1974-09-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-09-26 | 1978-03-28 | 1978-09-27 | $7700.00 | Window Closed / Lapsed |