US4025843A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Constant current base-drive circuit
Assignee: United States Department of the Navy
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Filing: 1976-04-28
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Granted: 1977-05-24
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Expires: 1996-04-28
Abstract
Abstract A control circuit for compensating for the change in drive current in a pe-width modulated control circuit of a power supply. Cos Mos three input NOR gates are controlled by applying an analog voltage proportional to the charge in drive current to the third input. A negative feedback loop is then provided to compensate for changing temperature.
Inventors
- 👤 Francis F. Parker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:48
CPC Classifications
H; H02; H02M; H02M1/00; H02M1/08; H02M3/00; H02M3/02; H02M3/04; H02M3/10; H02M3/145; H02M3/155; H02M3/156
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
108 words
A control circuit for providing a constant current in a base drive circuit comprising: (a) circuit means for sensing a change in the base drive current; (b) means coupled to said circuit sensing means for generating an analog voltage proportional to the sensed change in current in said base drive circuit; (c) gate circuit means having first and second inputs connected for gating an input signal and a third input coupled to said analog voltage generating means and being responsive to the analog voltage applied thereto for changing the amplitude of the signal gated by said gate circuit means for controlling the current in said base drive circuit.
Claim 2
Dependent Claim
108 words
A control circuit for providing a constant current in a base drive circuit comprising: (a) circuit means for sensing a change in the base drive current; (b) means coupled to said circuit sensing means for generating an analog voltage proportional to the sensed change in current in said base drive circuit; (c) gate circuit means having first and second inputs connected for gating an input signal and a third input coupled to said analog voltage generating means and being responsive to the analog voltage applied thereto for changing the amplitude of the signal gated by said gate circuit means for controlling the current in said base drive circuit.
Claim 3
Dependent Claim
21 words
The control circuit of claim 1 wherein said gate circuit means are of the Cos Mos three input NOR gate type.
Claim 4
Dependent Claim
50 words
The control circuit of claim 1 wherein said analog voltage generating means includes a transistor having its base and emitter connected in circuit with said base drive circuit and being responsive to a voltage change as the current in the base circuit changes to provide an output voltage proportional thereto.
Claim 5
Dependent Claim
22 words
The control circuit of claim 1 wherein said circuit sensing means includes a resistor connected in series with said base drive circuit.
Claim 6
Dependent Claim
51 words
The control circit of claim 4 wherein said analog sensing means includes a transistor having its base and emitter connected across said resistor and providing an output voltage at its collector proportional to the change in drive current and further including filter circuit means connected to the collector of said transistor.
Claim 7
Dependent Claim
59 words
The control circuit of claim 5 wherein said gate circuit means includes a Cos Mos three input NOR gate having its first and second inputs connected for gating an input signal and its third input connected to the collector of said transistor for controlling the amplitude of the gated signal in response to changes in the base drive current.
References Cited (Backward Citations)
US3523239A
Cited
US3629622A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-05-23 | 1980-11-22 | 1981-05-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-23 | 1984-11-22 | 1985-05-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-23 | 1988-11-22 | 1989-05-24 | $7700.00 | Window Closed / Lapsed |