Patent US3896394A successfully refreshed from Google Patents.
US3896394A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Arrangement for compensating the temperature drift of a power amplifier
Assignee: Thales SA
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Filing: 1974-09-20
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Granted: 1975-07-22
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Expires: 1994-09-20
Abstract
Abstract A bias arrangement makes it possible to automatically compensate the temperature drift occuring in an amplifier transistor. The bias arrangement formed by a first and a second transistor, supplies the bias voltage for an amplifier transistor, which voltage is variable by a variable resistor in the emitter lead of the first transistor. A third transistor identical to the first transistor assembled on the same radiator as the first transistor and the amplifier transistor supplies to the base of the amplifier transistor a voltage proportional to the temperature variations, with a coefficient which is chosen by means of a resistance bridge, in order to precisely compensate the variations the amplifier transistor.
Inventors
- 👤 Jose Marie Baro
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:14
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/30; H03F1/302; H03F3/00; H03F3/20; H03F3/24; H03F3/245
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
220 words
A power amplifier comprising at least one amplifier transistor having a base, an emitter and a collector, said amplifier transistor for amplifying an input signal being arranged in a common emitter configuration at least as far as the bias is concerned and an arrangement for supplying a bias voltage to the base of said amplifier transistor, said arrangement including: an auxiliary transistor having a base, a collector and an emitter, the emitter of said auxiliary transistor being coupled to the base of said amplifier transistor; a regulating transistor having a base, a collector and an emitter, the collector of said regulating transistor being coupled to the base of said auxiliary transistor; a resistor inserted between the base of said regulating transistor and the emitter of said auxiliary transistor; a further transistor, having the same characteristics as said regulating transistor and having a base, a collector and an emitter, the emitter of said further transistor being coupled to the emitter of said auxiliary transistor; a variable resistor inserted between the base of said regulating transistor and the base of said further transistor, the base and collector of said further transistor being coupled; and means for adjusting the emitter voltage of said regulating transistor; said amplifier transistor, said regulating transistor and said further transistor being assembled on one and the same radiator.
Claim 2
Dependent Claim
220 words
A power amplifier comprising at least one amplifier transistor having a base, an emitter and a collector, said amplifier transistor for amplifying an input signal being arranged in a common emitter configuration at least as far as the bias is concerned and an arrangement for supplying a bias voltage to the base of said amplifier transistor, said arrangement including: an auxiliary transistor having a base, a collector and an emitter, the emitter of said auxiliary transistor being coupled to the base of said amplifier transistor; a regulating transistor having a base, a collector and an emitter, the collector of said regulating transistor being coupled to the base of said auxiliary transistor; a resistor inserted between the base of said regulating transistor and the emitter of said auxiliary transistor; a further transistor, having the same characteristics as said regulating transistor and having a base, a collector and an emitter, the emitter of said further transistor being coupled to the emitter of said auxiliary transistor; a variable resistor inserted between the base of said regulating transistor and the base of said further transistor, the base and collector of said further transistor being coupled; and means for adjusting the emitter voltage of said regulating transistor; said amplifier transistor, said regulating transistor and said further transistor being assembled on one and the same radiator.
Claim 3
Dependent Claim
20 words
A power amplifier as claimed in claim 1 wherein said regulating transistor and said further transistor have a common substrate.
Claim 4
Dependent Claim
17 words
A power amplifier as claimed in claim 2 wherein said auxiliary transistor is assembled on said radiator.
References Cited (Backward Citations)
US3651346A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-21 | 1979-01-20 | 1979-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-21 | 1983-01-20 | 1983-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-21 | 1987-01-20 | 1987-07-22 | $7700.00 | Window Closed / Lapsed |