US4030023A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Temperature compensated constant voltage apparatus
Assignee: Nokia of America Corp
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Filing: 1976-05-25
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Granted: 1977-06-14
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Expires: 1996-05-25
Abstract
Abstract A temperature compensated constant voltage circuit utilizing a constant current supply circuit having a positive temperature coefficient of current for supplying current to a nearly constant voltage dropping circuit. The voltage dropping circuit includes a zener diode which has a negative temperature coefficient. The combination of the positive and negative coefficients cooperate to produce a temperature stable constant voltage circuit.
Inventors
- 👤 John L. Keith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:52
CPC Classifications
G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/18
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
129 words
Temperature compensated constant voltage apparatus comprising, in combination: power supply means including first and second terminal means; transistor means including base, emitter and collector means; first resistive means connected between said first terminal means and said base means; apparatus output means connected to said collector means for outputting a constant voltage; second resistive means connected between said emitter means and said second terminal means; first diode means, comprising two diodes connected in series each having the same direction of easy current flow, connected between said base means and said second terminal means; and second diode means, including at least a zener diode and a further diode having a direction of easy current flow opposite that of the zener diode, connected between said collector means and said first terminal means.
Claim 2
Dependent Claim
129 words
Temperature compensated constant voltage apparatus comprising, in combination: power supply means including first and second terminal means; transistor means including base, emitter and collector means; first resistive means connected between said first terminal means and said base means; apparatus output means connected to said collector means for outputting a constant voltage; second resistive means connected between said emitter means and said second terminal means; first diode means, comprising two diodes connected in series each having the same direction of easy current flow, connected between said base means and said second terminal means; and second diode means, including at least a zener diode and a further diode having a direction of easy current flow opposite that of the zener diode, connected between said collector means and said first terminal means.
Claim 3
Dependent Claim
35 words
Apparatus as claimed in claim 1 wherein the temperature coefficients of resistance of said first diode means are opposite and complementary the temperature coefficients of said second diode means for producing a temperature compensated circuit.
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) | 1980-06-13 | 1980-12-13 | 1981-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-13 | 1984-12-13 | 1985-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-13 | 1988-12-13 | 1989-06-14 | $7700.00 | Window Closed / Lapsed |