US3448289A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Logarthmic amplifier
Assignee: United States Department of the Navy
•
Filing: 1966-05-20
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Granted: 1969-06-03
•
Expires: 1986-05-20
Abstract
No abstract record available.
Inventors
- 👤 Paul E Harris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 03:29
CPC Classifications
G; G06; G06G; G06G7/00; G06G7/12; G06G7/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
184 words
IN A LOGARITHMIC AMPLIFIER CIRCUIT OF THE TYPE IN WHICH THE INPUT VOLTAGE IS PLACED ACROSS A SERIES RESISTORLOGGING DIODE COMBINATION, THE SIGNAL INPUT TERMINAL AND THE OUTPUT TERMINAL OF A FIRST DIFFERENTIAL OPERATIONAL AMPLIFIER ARE CONNECTED ACROSS THE LOGGING DIODE, AND THE LOGARITHMIC OUTPUT VOLTAGE OF THE CIRCUIT IS DERIVED FROM THE CURRENT THROUGH SAID DIODE, THE IMPROVEMENT COMPRISING A CIRCUIT FOR THE AUTOMATIC STABILIZATION OF THE BIAS OF THE LOGGING DIODE COMPRISING: A SECOND DIFFERENTIAL OPERATIONAL AMPLIFIER CONNECTED ACROSS SAID LOGGING DIODE TO RECEIVE AT ITS INPUT TERMINALS A VOLTAGE PROPORTIONAL TERMINAL OF SAID SECOND ACROSS SAID DIODE, THE OUTPUT TERMINAL OF SAID SECOND DIFFFERENTIAL OPERATIONAL AMPLIFIER BEING CONNECTED TO THE REFERENCE-BIAS INPUT TERMINAL OF SAID FIRST DIFFERENTIAL OPERATIONAL AMPLIFIER, WHEREBY ANY CHANGE IN BIAS ACROSS SAID DIODE RESULTS IN A CHANGE IN REFERENCE-BIAS VOLTAGE AT THE INPUT OF SAID FIRST DIFFERENTIAL OPERATIONAL AMPLIFIER WHICH COMPENSATES FOR SAID CHANGE IN BIAS ACROSS SAID DIODE; A BIAS-ERROR INTERGRATING CAPACITOR CONNECTED TO THE OUTPUT TERMINAL OF SAID SECOND DIFFERENTIAL AMPLIFIER; AND REFERENCE-BIAS SOURCE MEANS CONNECTED TO THE REFERENCEBIAS TERMINAL OF SAID SECOND DIFFERENTIAL AMPLIFIER.
Claim 2
Dependent Claim
184 words
IN A LOGARITHMIC AMPLIFIER CIRCUIT OF THE TYPE IN WHICH THE INPUT VOLTAGE IS PLACED ACROSS A SERIES RESISTORLOGGING DIODE COMBINATION, THE SIGNAL INPUT TERMINAL AND THE OUTPUT TERMINAL OF A FIRST DIFFERENTIAL OPERATIONAL AMPLIFIER ARE CONNECTED ACROSS THE LOGGING DIODE, AND THE LOGARITHMIC OUTPUT VOLTAGE OF THE CIRCUIT IS DERIVED FROM THE CURRENT THROUGH SAID DIODE, THE IMPROVEMENT COMPRISING A CIRCUIT FOR THE AUTOMATIC STABILIZATION OF THE BIAS OF THE LOGGING DIODE COMPRISING: A SECOND DIFFERENTIAL OPERATIONAL AMPLIFIER CONNECTED ACROSS SAID LOGGING DIODE TO RECEIVE AT ITS INPUT TERMINALS A VOLTAGE PROPORTIONAL TERMINAL OF SAID SECOND ACROSS SAID DIODE, THE OUTPUT TERMINAL OF SAID SECOND DIFFFERENTIAL OPERATIONAL AMPLIFIER BEING CONNECTED TO THE REFERENCE-BIAS INPUT TERMINAL OF SAID FIRST DIFFERENTIAL OPERATIONAL AMPLIFIER, WHEREBY ANY CHANGE IN BIAS ACROSS SAID DIODE RESULTS IN A CHANGE IN REFERENCE-BIAS VOLTAGE AT THE INPUT OF SAID FIRST DIFFERENTIAL OPERATIONAL AMPLIFIER WHICH COMPENSATES FOR SAID CHANGE IN BIAS ACROSS SAID DIODE; A BIAS-ERROR INTERGRATING CAPACITOR CONNECTED TO THE OUTPUT TERMINAL OF SAID SECOND DIFFERENTIAL AMPLIFIER; AND REFERENCE-BIAS SOURCE MEANS CONNECTED TO THE REFERENCEBIAS TERMINAL OF SAID SECOND DIFFERENTIAL AMPLIFIER.
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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) | 1972-06-02 | 1972-12-02 | 1973-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-06-02 | 1976-12-02 | 1977-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-06-02 | 1980-12-02 | 1981-06-03 | $7700.00 | Window Closed / Lapsed |