US3573646A
Expired / Lapsed
US
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High stability emitter follower
Assignee: United States Department of the Air Force
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Filing: 1969-07-17
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Granted: 1971-04-06
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Expires: 1989-07-17
Abstract
Abstract An emitter follower apparatus having a low impedance output which is independent of temperature by cancelling the voltage drifts due to base-emitter diode changes in two cascaded emitter followers.
Inventors
- 👤 Pieter De Wit
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 10:34
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/30; H03F1/302; H03F3/00; H03F3/50
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
112 words
An emitter follower apparatus for providing a stable output voltage over a wide temperature range comprising in combination: a first emitter follower having a first predetermined voltage drop, said first emitter follower having a first input and first output; a second emitter follower having a second predetermined voltage drop, said second emitter follower having a second input and second output, said first and second emitter followers being operated at substantially equal current levels, said first predetermined voltage drop being substantially equal to but opposite to said second predetermined voltage drop, said first input receiving signal, said first output being directly connected to said second input, and second output providing an output signal.
Claim 2
Dependent Claim
112 words
An emitter follower apparatus for providing a stable output voltage over a wide temperature range comprising in combination: a first emitter follower having a first predetermined voltage drop, said first emitter follower having a first input and first output; a second emitter follower having a second predetermined voltage drop, said second emitter follower having a second input and second output, said first and second emitter followers being operated at substantially equal current levels, said first predetermined voltage drop being substantially equal to but opposite to said second predetermined voltage drop, said first input receiving signal, said first output being directly connected to said second input, and second output providing an output signal.
Claim 3
Dependent Claim
55 words
An emitter follower apparatus as described in claim 1 wherein said first emitter follower comprises a transistor having a base, collector and emitter electrodes, said base electrode comprising said first input, said emitter electrode comprising said first output, said base and emitter electrodes forming a junction, and said junction having a first predetermined voltage drop.
Claim 4
Dependent Claim
55 words
An emitter follower apparatus as described in claim 1 wherein said second emitter foLlower comprises a transistor having a base, collector and emitter electrodes, said base electrode comprising said second input, said emitter electrode comprising said second output, said base and emitter electrodes forming a junction, and said junction having a second predetermined voltage drop.
Claim 5
Dependent Claim
21 words
An emitter follower apparatus as described in claim 2 wherein said transistor of said first emitter follower comprises an NPN device.
Claim 6
Dependent Claim
21 words
An emitter follower apparatus as described in claim 3 wherein said transistor of said second emitter follower comprises a PNP device.
References Cited (Backward Citations)
US2963656A
Cited
US3100876A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-05 | 1974-10-05 | 1975-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-05 | 1978-10-05 | 1979-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-05 | 1982-10-05 | 1983-04-06 | $7700.00 | Window Closed / Lapsed |