US3862367A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Amplifying circuit for use with a transducer
Assignee: Sony Corp
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Filing: 1973-02-28
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Granted: 1975-01-21
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Expires: 1993-02-28
Abstract
Abstract An amplifying circuit for use with a transducer includes a pair of field-effect transistors which are of different conductive types from each other and each of which has gate, drain and source electrodes. The gate electrodes of the field-effect transistors are connected to each other and are further connected to an output terminal of an electrostatic type mechanicalelectrical transducer, while the source electrodes of the fieldeffect transistors are connected to each other and are further connected to an output circuit. One of the drain electrodes is connected to a voltage source and the other drain electrode is connected to the circuit ground.
Inventors
- 👤 Osamu Kono
- 👤 Takeshi Matsudaira
- 👤 Makoto Ishikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:59
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/181; H03F3/183; H03F3/185; H03F3/1855
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
161 words
An amplifying circuit for use with a signal source comprising first and second field-effect transistors which are of different conductive types, each of which has gate, drain and source electrodes, the gate electrodes of the first and second fieldeffect transistors being connected to each other, a resistor connecting the source electrodes of the first and second fieldeffect transistors to each other, means for supplying power to the drain electrode of the first field-effect transistor, means for connecting the Signal source between the interconnected gate electrodes of the first and second field-effect transistors and the drain electrode of the second field-effect transistor, and an output circuit including first and second capacitors connected to each other in a series circuit which is connected in parallel with said resistor, and a transformer having a primary winding connected, at one end, to said series circuit between said first and second capacitors and, at its other end, to the drain electrode of the second field-effect transistor.
Claim 2
Dependent Claim
161 words
An amplifying circuit for use with a signal source comprising first and second field-effect transistors which are of different conductive types, each of which has gate, drain and source electrodes, the gate electrodes of the first and second fieldeffect transistors being connected to each other, a resistor connecting the source electrodes of the first and second fieldeffect transistors to each other, means for supplying power to the drain electrode of the first field-effect transistor, means for connecting the Signal source between the interconnected gate electrodes of the first and second field-effect transistors and the drain electrode of the second field-effect transistor, and an output circuit including first and second capacitors connected to each other in a series circuit which is connected in parallel with said resistor, and a transformer having a primary winding connected, at one end, to said series circuit between said first and second capacitors and, at its other end, to the drain electrode of the second field-effect transistor.
Claim 3
Dependent Claim
20 words
An amplifying circuit as recited in claim 1 wherein the signal source is a mechanical-electrical transducer of the electrostatic type.
Claim 4
Dependent Claim
148 words
An amplifying circuit as recited in claim 1, in which said means for connecting the signal source between the gate electrodes of the field-effect transistors and the drain electrode of the second field-effect transistor includes third and fourth field-effect transistors which are of different conductive types and each of which has gate, drain and source electrodes, means for supplying power to the drain electrode of said third field-effect transistor, means for connecting the source electrodes of said third and fourth field-effect transistors to each other and to the interconnected gate electrodes of said first and second field-effect transistors, means for connecting the gate electrodes of said third and fourth field-effect transistors to each other and to one side of the signal source, and means for connecting the drain electrodes of said second and fourth field-effect transistors to each other and to the other side of the signal source.
Claim 5
Dependent Claim
32 words
An amplifying circuit as recited in claim 3, wherein said third and fourth field-effect transistors are selected to have smaller gate leak currents than those of the first and second field-effect transistors.
Claim 6
Dependent Claim
59 words
An amplifying circuit as recited in claim 3, wherein said means connecting the source electrodes of said third and fourth field-effect transistors to each other includes second and third resistors in series with each other, and with the connecting point between said second and third resistors being connected to the gate electrodes of said first and second field-effect transistors.
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) | 1978-01-20 | 1978-07-22 | 1979-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-20 | 1982-07-22 | 1983-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-20 | 1986-07-22 | 1987-01-21 | $7700.00 | Window Closed / Lapsed |