Patent US3714600A successfully refreshed from Google Patents.
US3714600A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transistor amplifier
Assignee: US Philips Corp
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Filing: 1971-03-16
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Granted: 1973-01-30
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Expires: 1991-03-16
Abstract
Abstract The invention relates to a transistor amplifier in which steps have been taken to reduce the input current of the amplifier. The steps consist in the inclusion of a measuring transistor in the collector circuit of an input transistor of the amplifier and in the inclusion of a ''''current mirror'''' between the base of the measuring transistor and the base of the input transistor. The base of the measuring transistor has been connected to the lowresistance input of the current mirror and the base of the input transistor has been connected to the high-resistance output of the current mirror.
Inventors
- 👤 K Kuijk
- 👤 A Hoogendoorn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:25
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/56; G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20; G05F3/26; G05F3/265; H01; H01R; H01R12/00; H01R12/70; H01R12/71; H01R12/712; H01R12/714; H03F3/00; H03F3/34; H03F3/343; H03F3/347; H03F3/45; H03F3/45071; H03F3/45076; H03F3/4508; H03F3/45085; H03F3/45089
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
181 words
A transistor amplifier, comprising a first transistor having a base, a collector and an emitter, the base of the first transistor comprising the input to the amplifier, means connecting the emitter of the first transistor to a constant potential, a measuring transistor having a base and a collectoremitter path, and impedance, means connecting the collector of the first transistor through a series combination of the impedance and the collector emitter path of the measuring transistor to a second constant potential different from the first constant potential, a current-controlled current source having an input terminal, an output terminal and a common terminal for providing an output current equal to the input current, the resistance between the input terminal and the common terminal being substantially smaller than the resistance between the output terminal and the common terminal, means connecting the common terminal of the current source to a constant potential, means connecting the base of the measuring transistor to the input terminal of the current source, and means connecting the output terminal of the current source to the base of the first transistor.
Claim 2
Dependent Claim
181 words
A transistor amplifier, comprising a first transistor having a base, a collector and an emitter, the base of the first transistor comprising the input to the amplifier, means connecting the emitter of the first transistor to a constant potential, a measuring transistor having a base and a collectoremitter path, and impedance, means connecting the collector of the first transistor through a series combination of the impedance and the collector emitter path of the measuring transistor to a second constant potential different from the first constant potential, a current-controlled current source having an input terminal, an output terminal and a common terminal for providing an output current equal to the input current, the resistance between the input terminal and the common terminal being substantially smaller than the resistance between the output terminal and the common terminal, means connecting the common terminal of the current source to a constant potential, means connecting the base of the measuring transistor to the input terminal of the current source, and means connecting the output terminal of the current source to the base of the first transistor.
Claim 3
Dependent Claim
181 words
A transistor amplifier, comprising a first transistor having a base, a collector and an emitter, the base of the first transistor comprising the input to the amplifier, means connecting the emitter of the first transistor to a constant potential, a measuring transistor having a base and a collector-emitter path, and impedance, means connecting the collector of the first transistor through a series combination of the impedance and the collector emitter path of the measuring transistor to a second constant potential different from the first constant potential, a current-controlled current source having an input terminal, an output terminal and a common terminal for providing an output current equal to the input current, the resistance between the input terminal and the common terminal being substantially smaller than the resistance between the output terminal and the common terminal, means connecting the common terminal of the current source to a constant potential, means connecting the base of the measuring transistor to the input terminal of the current source, and means connecting the output terminal of the current source to the base of the first transistor.
Claim 4
Dependent Claim
181 words
A transistor amplifier, comprising a first transistor having a base, a collector and an emitter, the base of the first transistor comprising the input to the amplifier, means connecting the emitter of the first transistor to a constant potential, a measuring transistor having a base and a collector-emitter path, and impedance, means connecting the collector of the first transistor through a series combination of the impedance and the collector emitter path of the measuring transistor to a second constant potential different from the first constant potential, a current-controlled current source having an input terminal, an output terminal and a common terminal for providing an output current equal to the input current, the resistance between the input terminal and the common terminal being substantially smaller than the resistance between the output terminal and the common terminal, means connecting the common terminal of the current source to a constant potential, means connecting the base of the measuring transistor to the input terminal of the current source, and means connecting the output terminal of the current source to the base of the first transistor.
Claim 5
Dependent Claim
136 words
A transistor amplifier as claimed in claim 1, wherein the means connecting the common terminal of the current source to a constant potential comprises means connecting the common terminal of the current source to the collector of the measuring transistor. 3. A transistor amplifier as claimed in claim 1, wherein the current controlled current source comprises a third transistor having a base, an emitter and a collector, means connecting the emitter of the third transistor to the common terminal of the current controlled current source, means connecting the collector of the third transistor to the output terminal of the current controlled current source, means connecting the base of the third transistor to the input terminal of the current controlled current source, and a diode connected in parallel with the base and emitter of the third transistor.
Claim 6
Dependent Claim
78 words
A transistor amplifier as claimed in claim 3, further comprising a fourth transistor having a base, an emitter and a collector, means connecting the base of the fourth transistor to the collector of the third transistor, means connecting the collector of the fourth transistor to the base of the third transistor, and wherein the means connecting the base of the third transistor to the output terminal of the current source comprises the collector-emitter path of the fourth transistor.
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) | 1976-01-30 | 1976-07-31 | 1977-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-30 | 1980-07-31 | 1981-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-30 | 1984-07-31 | 1985-01-30 | $7700.00 | Window Closed / Lapsed |