Patent US3870896A successfully refreshed from Google Patents.
US3870896A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controllable current source
Assignee: Lorain Products Corp
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Filing: 1973-09-11
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Granted: 1975-03-11
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Expires: 1993-09-11
Abstract
Abstract A circuit for providing a current the magnitude of which is determined by an externally generated control signal and which is substantially independent of the impedance of the load to which the current is applied. A current generating network generates an output current in accordance with the algebraic sum of the control signals applied to the inputs thereof. One of these inputs is energized by an externally generated control signal which sets the desired value of output current. A second of these inputs is controlled in accordance with a feedback signal indicative of the output current to assure that attempted deviations of the output current from the desired value are counteracted before they substantially affect the level of current through the load.
Inventors
- 👤 Frederick Kiko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:16
CPC Classifications
G; G05; G05F; G05F1/00; G05F1/10; G05F1/46; G05F1/461
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
209 words
In a circuit for generating two currents which are substantially eQual and opposite and which have magnitudes that are substantially independent of the impedance of the circuitry to which the currents are applied, the combination of, a circuit input, first and second circuit outputs, first and second current generating means each having inverting input means and output means, first and second current sampling means for generating respective signals which vary in accordance with the currents at respective circuit outputs, means for connecting the input means of said first generating means to said circuit input, means for connecting said first sampling means between the output means of said first generating means and said first circuit output, means for connecting the input means of said second generating means to the output means of said first generating means, means for connecting said second sampling means between the output means of said second generating means and said second circuit output, feedback means for energizing the input means of said first generating means with a feedback signal indicative of the current through both said first and said second sampling means and means for connecting said feedback means to said first and second sampling means and to the input means of said first generating means.
Claim 2
Dependent Claim
209 words
In a circuit for generating two currents which are substantially eQual and opposite and which have magnitudes that are substantially independent of the impedance of the circuitry to which the currents are applied, the combination of, a circuit input, first and second circuit outputs, first and second current generating means each having inverting input means and output means, first and second current sampling means for generating respective signals which vary in accordance with the currents at respective circuit outputs, means for connecting the input means of said first generating means to said circuit input, means for connecting said first sampling means between the output means of said first generating means and said first circuit output, means for connecting the input means of said second generating means to the output means of said first generating means, means for connecting said second sampling means between the output means of said second generating means and said second circuit output, feedback means for energizing the input means of said first generating means with a feedback signal indicative of the current through both said first and said second sampling means and means for connecting said feedback means to said first and second sampling means and to the input means of said first generating means.
Claim 3
Dependent Claim
209 words
In a circuit for generating two currents which are substantially eQual and opposite and which have magnitudes that are substantially independent of the impedance of the circuitry to which the currents are applied, the combination of, a circuit input, first and second circuit outputs, first and second current generating means each having inverting input means and output means, first and second current sampling means for generating respective signals which vary in accordance with the currents at respective circuit outputs, means for connecting the input means of said first generating means to said circuit input, means for connecting said first sampling means between the output means of said first generating means and said first circuit output, means for connecting the input means of said second generating means to the output means of said first generating means, means for connecting said second sampling means between the output means of said second generating means and said second circuit output, feedback means for energizing the input means of said first generating means with a feedback signal indicative of the current through both said first and said second sampling means and means for connecting said feedback means to said first and second sampling means and to the input means of said first generating means.
Claim 4
Dependent Claim
209 words
In a circuit for generating two currents which are substantially eQual and opposite and which have magnitudes that are substantially independent of the impedance of the circuitry to which the currents are applied, the combination of, a circuit input, first and second circuit outputs, first and second current generating means each having inverting input means and output means, first and second current sampling means for generating respective signals which vary in accordance with the currents at respective circuit outputs, means for connecting the input means of said first generating means to said circuit input, means for connecting said first sampling means between the output means of said first generating means and said first circuit output, means for connecting the input means of said second generating means to the output means of said first generating means, means for connecting said second sampling means between the output means of said second generating means and said second circuit output, feedback means for energizing the input means of said first generating means with a feedback signal indicative of the current through both said first and said second sampling means and means for connecting said feedback means to said first and second sampling means and to the input means of said first generating means.
Claim 5
Dependent Claim
72 words
A circuit as set forth in claim 1 including a phase-reversing circuit input, inverting means having input means and output means, said inverting means serving as means for generating a signal at the output means thereof which is substantially equal and opposite to the signal at the input means thereof, and means for connecting said inverting means between said phase-reversing circuit input and the input means of said first current generating means.
Claim 6
Dependent Claim
178 words
In a circuit for generating two currents which are substantially equal and opposite and which have magnitudes that are substantially independent of the impedance of the circuitry to which the currents are applied, the combination of, first and second circuit inputs, first and second circuit outputs, current generating means having input means and first and second output means, said current generating means serving as means for establishing substantially equal and opposite voltages at the output means thereof in accordance with the voltage at the input means thereof, first and second current sampling means, means for connecting said current sampling means between respective output means of said current generating means and respective circuit outputs, means for connecting the input means of said current generating means to said first and second circuit inputs, feedback means for energizing the input means of said current generating means in accordance with the current through both said first and said second current sampling means and means for connecting said feedback means to said sampling means and to the input means of said generating means.
Claim 7
Dependent Claim
178 words
In a circuit for generating two currents which are substantially equal and opposite and which have magnitudes that are substantially independent of the impedance of the circuitry to which the currents are applied, the combination of, first and second circuit inputs, first and second circuit outputs, current generating means having input means and first and second output means, said current generating means serving as means for establishing substantially equal and opposite voltages at the output means thereof in accordance with the voltage at the input means thereof, first and second current sampling means, means for connecting said current sampling means between respective output means of said current generating means and respective circuit outputs, means for connecting the input means of said current generating means to said first and second circuit inputs, feedback means for energizing the input means of said current generating means in accordance with the current through both said first and said second current sampling means and means for connecting said feedback means to said sampling means and to the input means of said generating means.
Claim 8
Dependent Claim
62 words
A circuit as set forth in claim 3 in which the means for connecting the input means of said generating means to said first and second circuit inputs includes a connector for connecting the input means of said generating means to said first circuit input and inverting means for connecting the input means of said generating means to said second circuit input.
Claim 9
Dependent Claim
35 words
A circuit as set forth in claim 3 in which said feedback means includes first, component feedback means for providing an inverted feedback signal and second, component feedback means for providing a non-inverted feedback signal.
Claim 10
Dependent Claim
181 words
In a circuit for generating two currents which are substantially equal and opposite and which have magnitudes that are substantially independent of the impedance of the circuitry to which the currents are applied, the combination of, a circuit input, first and second circuit outputs, current generating means having input means and first and second output means, said current generating means serving as means for establishing substantially equal and opposite voltages at said first and second output means in accordance with the voltage at thE input means thereof, first and second current sampling means, means for connecting said first and second current sampling means in current sensing relationship between respective output means of said current generating means and respective circuit outputs, means for connecting the input means of said current generating means to said circuit input, feedback means for energizing the input means of said current generating means in accordance with the currents sensed by both of said current sampling means and means for connecting said feedback means to said sampling means and to the input means of said current generating means.
Claim 11
Dependent Claim
181 words
In a circuit for generating two currents which are substantially equal and opposite and which have magnitudes that are substantially independent of the impedance of the circuitry to which the currents are applied, the combination of, a circuit input, first and second circuit outputs, current generating means having input means and first and second output means, said current generating means serving as means for establishing substantially equal and opposite voltages at said first and second output means in accordance with the voltage at thE input means thereof, first and second current sampling means, means for connecting said first and second current sampling means in current sensing relationship between respective output means of said current generating means and respective circuit outputs, means for connecting the input means of said current generating means to said circuit input, feedback means for energizing the input means of said current generating means in accordance with the currents sensed by both of said current sampling means and means for connecting said feedback means to said sampling means and to the input means of said current generating means.
Claim 12
Dependent Claim
152 words
A circuit as set forth in claim 6 in which said feedback means includes first, second, third and fourth resistance means, and in which said means for connecting said feedback means to said current sampling means and to the input means of said current generating means includes means for connecting said first resistance means to a first end of said first current sampling means and to the input means of said generating means, means for connecting said second resistance means to a second end of said second current sampling means and to the input means of said generating means, means for connecting said third resistance means to a second end of said first current sampling means and to the input means of said generating means and means for connecting said fourth resistance means to a first end of said second current sampling means and to the input means of said generating means.
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) | 1978-03-10 | 1978-09-09 | 1979-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-10 | 1982-09-09 | 1983-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-10 | 1986-09-09 | 1987-03-11 | $7700.00 | Window Closed / Lapsed |