Patent US3125693A successfully refreshed from Google Patents.
US3125693A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Constant
Assignee: —
•
Filing: —
•
Granted: 1964-03-17
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Expires: 1981-03-17
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:49
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/56
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
162 words
AN AMPLIFIER CIRCUIT HAVING A HIGH INPUT IMPEDANCE FOR A PHOTODIODE SENSING ELEMENT COMPRISING A PHOTODIODE CONNECTED BETWEEN A SOURCE OF BIASING POTENTIAL AND A UNILATERAL IMPEDANCE ELEMENT, SAID UNILATERAL IMPEDANCE ELEMENT BEING FURTHER COUPLED TO A REFERENCE POINT, A FIRST PREAMPLIFIER STAGE HAVING ITS INPUT CONNECTED TO THE JUNCTION OF SAID PHOTODIODE AND SAID UNILATERAL IMPEDANCE ELEMENT, MEANS COUPLING THE OUTPUT OF SAID FIRST PREAMPLIFIER STAGE TO THE OUTPUT OF SAID AMPLIFIER CIRCUIT, A FIRST CONSTANT CURRENT PATH INCLUDING A CONSTANT CURRENT SOURCE COUPLED BETWEEN THE OUTPUT OF SAID FIRST PREAMPLIFIER STAGE AND SAID REFERENCE POINT SUCH THAT ANY CHANGE IN CURRENT FLOW THROUGH SAID FIRST PREAMPLIFIER STAGE DUE TO LIGHT ENERGY UPON SAID PHOTODIODE CAUSES A CURRENT CHANGE AT THE OUTPUT OF SAID AMPLIFIER CIRCUIT, AND A SECOND CONSTANT CURRENT PATH COMPRISING A RESISTOR HAVING ONE TERMINAL CONNECTED TO SAID JUNCTION AND ITS OTHER TERMINAL COUPLED TO THE OUTPUT OF SAID AMPLIFIER CIRCUIT BY WAY OF A VOLTAGE REGULATING ELEMENT.
References Cited (Backward Citations)
US3069552A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-03-17 | 1967-09-16 | 1968-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-03-17 | 1971-09-16 | 1972-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-03-17 | 1975-09-16 | 1976-03-17 | $7700.00 | Window Closed / Lapsed |