Patent US3571735A successfully refreshed from Google Patents.
US3571735A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Detection circuit including compensation for the threshold of the forward characteristic of a semiconductor junction
Assignee: Telecommunications Radioelectriques et Telephoniques SA TRT
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Filing: 1968-08-26
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Granted: 1971-03-23
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Expires: 1988-08-26
Abstract
Abstract A transistor detector circuit features a diode coupled in series with the base of the transistor to temperature compensate the circuit against temperature shifts in the base-emitter threshold voltage. A second transistor and a second diode can also be used for detecting signals of greater amplitude.
Inventors
- 👤 Jean Martial Ducamus
- 👤 Jacques Andrieu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:55
CPC Classifications
H; H03; H03D; H03D1/00; H03D1/08; H03D1/10
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
90 words
A detector circuit comprising means for receiving signals to be detected; means for detecting said signals comprising a first transistor having emitter, base, and collector electrodes; means for biasing said first transistor comprising a source of bias potential and a resistor coupled between said bias source and said base; means for compensating said transistor against temperature dependent threshold shifts comprising a first temperature compensating unidirectional conducting means serially coupled between said receiving means and said base; and means for filtering the detected output of said transistor coupled to said emitter.
Claim 2
Dependent Claim
90 words
A detector circuit comprising means for receiving signals to be detected; means for detecting said signals comprising a first transistor having emitter, base, and collector electrodes; means for biasing said first transistor comprising a source of bias potential and a resistor coupled between said bias source and said base; means for compensating said transistor against temperature dependent threshold shifts comprising a first temperature compensating unidirectional conducting means serially coupled between said receiving means and said base; and means for filtering the detected output of said transistor coupled to said emitter.
Claim 3
Dependent Claim
61 words
A detector as claimed in claim 1, wherein said unidirectional conducting means comprises a first diode and a second transistor having emitter and base coupled to said first diode and said base of said first transistor respectively, and said temperature compensation means further comprises a second temPerature compensating diode coupled between said emitter of said first transistor and said filter means.
Claim 4
Dependent Claim
21 words
A circuit as claimed in claim 1, wherein said filter comprises a resistor and a capacitor parallel coupled to each other.
Claim 5
Dependent Claim
20 words
A circuit as claimed in claim 1, wherein said unidirectional conducting means comprises the emitter-base junction of a third transistor.
Claim 6
Dependent Claim
26 words
A circuit as claimed in claim 1, wherein the current flowing through said bias resistor and diode is equal to the emitter current of said transistor.
References Cited (Backward Citations)
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US3003122A
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US3275941A
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US3249880A
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US3248572A
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US3382445A
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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) | 1974-03-22 | 1974-09-21 | 1975-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-22 | 1978-09-21 | 1979-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-22 | 1982-09-21 | 1983-03-23 | $7700.00 | Window Closed / Lapsed |