Patent US3937986A successfully refreshed from Google Patents.
US3937986A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Linear waveform generator
Assignee: Xerox Ltd
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Filing: 1974-03-11
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Granted: 1976-02-10
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Expires: 1994-03-11
Abstract
Abstract A transistor timing ramp generator having collector, emitter and base electrodes and having a capacitor connected between collector and base, a resistance connected between base and emitter, the emitter being connected directly to a first input terminal, a resistive load in the collector circuit and means for supplying a signal to a second input terminal in the collector circuit and the input terminal to switch on the transistor when said signal is supplied, and to operate in the region where the base-emitter potential is substantially constant, thus providing a constant current to charge the capacitor and thereby obtaining a linear timing ramp at the collector which approaches the potential of said signal.
Inventors
- 👤 Arnold Wilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:32
CPC Classifications
H; H03; H03K; H03K4/00; H03K4/06; H03K4/08; H03K4/48; H03K4/50; H03K4/56; G; G04; G04F; G04F10/00; G04F10/10
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
127 words
A timing ramp generating comprising first and second transistors each having collector, emitter and base electrodes, a capacitor connected between base of said first transistor and the collector of said second transistor, a resistance connected between the base and emitter of said first transistor, the emitter of said first transistor being connected to a first terminal and the base of said second transistor, a resistive load coupled intermediate the collector of said second transistor, and a second terminal, said second terminal connected to the collector of said first transistor, source of d.c. voltage connected across said first and second terminals, whereby a constant current charges the capacitor and a linear timing ramp is generated at the collector of said second transistor which approaches the applied d.c. voltage.
Claim 2
Dependent Claim
127 words
A timing ramp generating comprising first and second transistors each having collector, emitter and base electrodes, a capacitor connected between base of said first transistor and the collector of said second transistor, a resistance connected between the base and emitter of said first transistor, the emitter of said first transistor being connected to a first terminal and the base of said second transistor, a resistive load coupled intermediate the collector of said second transistor, and a second terminal, said second terminal connected to the collector of said first transistor, source of d.c. voltage connected across said first and second terminals, whereby a constant current charges the capacitor and a linear timing ramp is generated at the collector of said second transistor which approaches the applied d.c. voltage.
Claim 3
Dependent Claim
179 words
A timing ramp generator including a main transistor having collector, emitter and base electrodes and having a capacitor connected between collector and base, a resistance connected between base and emitter, the emitter being connected directly to a first terminal, a resistive load in the collector circuit, means for supplying a d.c. voltage across a second input terminal in the collector circuit and the first terminal to switch on the transistor when said voltage is supplied, and to operate in the region where the base-emitter potential is substantially constant, thus providing a constant current to charge the capacitor and thereby obtaining a linear timing ramp at the collector which approaches the potential of said signal, a constant current device in the collector circuit of said main transistor, said constant current device includes a second transistor of opposite conductivity type to said main transistor, said second transistor havings its base connected to a reference potential, the collector-emitter circuit of said second transistor being connected in series with the collector emitter circuit of said main transistor across said first and second terminals.
Claim 4
Dependent Claim
179 words
A timing ramp generator including a main transistor having collector, emitter and base electrodes and having a capacitor connected between collector and base, a resistance connected between base and emitter, the emitter being connected directly to a first terminal, a resistive load in the collector circuit, means for supplying a d.c. voltage across a second input terminal in the collector circuit and the first terminal to switch on the transistor when said voltage is supplied, and to operate in the region where the base-emitter potential is substantially constant, thus providing a constant current to charge the capacitor and thereby obtaining a linear timing ramp at the collector which approaches the potential of said signal, a constant current device in the collector circuit of said main transistor, said constant current device includes a second transistor of opposite conductivity type to said main transistor, said second transistor havings its base connected to a reference potential, the collector-emitter circuit of said second transistor being connected in series with the collector emitter circuit of said main transistor across said first and second terminals.
References Cited (Backward Citations)
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US3313955A
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US3509367A
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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) | 1979-02-09 | 1979-08-11 | 1980-02-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-02-09 | 1983-08-11 | 1984-02-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-02-09 | 1987-08-11 | 1988-02-10 | $7700.00 | Window Closed / Lapsed |