US3649906A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Programmable dc power supply
Assignee: Unisys Corp
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Filing: 1970-09-08
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Granted: 1972-03-14
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Expires: 1990-09-08
Abstract
Abstract A programmable DC power supply including a proportionally controlled transistor connected in series with the load for varying the load current in accordance with the magnitude of a control signal applied to the transistor. A detector coupled across the transistor functions to sense high and low voltage thresholds and thereupon select an incrementally higher or lower voltage for application to the load to assure that the transistor operates continuously in its proportional range, thereby enabling the input signal to maintain control of the load current.
Inventors
- 👤 Richard A Carpentier
- 👤 Spencer A Shriver
- 👤 Richard C Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:39
CPC Classifications
G; G05; G05F; G05F1/00; G05F1/10; G05F1/46; G05F1/56; B; B63; B63G; B63G9/00; B63G9/06
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
240 words
A power source for supplying bipolar variable DC current to a load in accordance with the polarity and magnitude of an input control signal applied to said source comprising a bridge circuit having input terminals (A) and (B) for receiving the voltage applied thereto and output terminals (C) and (D) adapted for connection to the load, said bridge circuit including first and second switching elements connected respectively between input terminal A and output terminals (C) and (D) and first and second proportionally controlled transistors connected respectively between input terminal (B) and output terminals (C) and (D), means for applying the input control signal to the switching elements of said bridge in a manner to close one of said switching elements and open the other switching element for one polarity and conversely for the other polarity of the control signal, means for applying the input control signal to the proportionally controlled transistors of said bridge in a manner to open circuit the one in series with the closed switching element and regulate the impedance of the other in accordance with the magnitude of the control signal, means responsive to the voltage across the active proportionally controlled transistor for providing a step-up signal at one level of the voltage thereacross and a stepdown signal at another level of voltage thereacross, and means responsive to the step-up and stepdown signals for incrementally changing the voltage applied to the input terminals of said bridge.
Claim 2
Dependent Claim
240 words
A power source for supplying bipolar variable DC current to a load in accordance with the polarity and magnitude of an input control signal applied to said source comprising a bridge circuit having input terminals (A) and (B) for receiving the voltage applied thereto and output terminals (C) and (D) adapted for connection to the load, said bridge circuit including first and second switching elements connected respectively between input terminal A and output terminals (C) and (D) and first and second proportionally controlled transistors connected respectively between input terminal (B) and output terminals (C) and (D), means for applying the input control signal to the switching elements of said bridge in a manner to close one of said switching elements and open the other switching element for one polarity and conversely for the other polarity of the control signal, means for applying the input control signal to the proportionally controlled transistors of said bridge in a manner to open circuit the one in series with the closed switching element and regulate the impedance of the other in accordance with the magnitude of the control signal, means responsive to the voltage across the active proportionally controlled transistor for providing a step-up signal at one level of the voltage thereacross and a stepdown signal at another level of voltage thereacross, and means responsive to the step-up and stepdown signals for incrementally changing the voltage applied to the input terminals of said bridge.
Claim 3
Dependent Claim
83 words
The apparatus of claim 1 wherein said means for applying the input control signal to the proportionally controlled transistors includes inverting and noninverting driver amplifiers said inverting driver amplifier having its input connected to receive the input control signal and its output connected to the base of one of said proportionally controlled transistors, and said noninverting driver amplifier having its input connected to receive the input control signal and its output connected to the base of the other of said proportionally controlled transistors.
Claim 4
Dependent Claim
174 words
The apparatus of claim 2 including first resistance means coupled to said one proportionally controlled transistor to provide a first feedback signal representative of the current flowing through said load when said one transistor is active, means coupling said first resistance means to said inverting driver amplifier for algebraically summing therein the input control and first feedback signals to provide a drive signal which controls said one proportionally controlled transistor to regulate the load current in accordance with the magnitude of the input control signal for one polarity thereof, second resistance means coupled to said other proportionally controlled transistor to provide a second feedback signal representative of the current flowing through said load when said other transistor is active, and means coupling said second resistance means to said noninverting driver amplifier for algebraically summing therein the input control and second feedback signals to provide another drive signal which controls said other proportionally controlled transistor to regulate the load current in accordance with the magnitude of the input control signal for the opposite polarity thereof.
Claim 5
Dependent Claim
86 words
The apparatus of claim 3 wherein said means for applying the input control signal to said bridge switching elements includes a zero detector comprising first and second signal inverting amplifier stages, the input of said first inverting amplifier stage being connected to receive the input control signal, the output of said first inverting amplifier stage being connected to drive the second switching element of said bridge, and the output of said second inverting amplifier stage being connected to drive the first switching element of said bridge.
Claim 6
Dependent Claim
153 words
The apparatus of claim 4 wherein said means responsive to the voltage across the active proportionally controlled transistor includes a comparator switch circuit comprising, a first switch serially connected with a resistor and a diode, a second switch serially connected with an additional resistor and an additional diode, said first switch being connected to be actuated by the signal at the output of the first inverting amplifier stage of said zero detector, said second switch being connected to be actuated by the signal at the output of the second inverting amplifier stage of said zero detector, the junction of said resistor and said diode being connected to output terminal (D) of said bridge circuit, the junction of said additional resistor and said additional diode being connected to output terminal (C) of said bridge circuit, and the side of said diodes opposite said junctions being coupled together at the output of said comparator switch.
Claim 7
Dependent Claim
56 words
The apparatus of claim 5 wherein said means responsive to the voltage across the active proportionally controlled transistor further includes a comparator comprising first and second threshold detectors each having its input connected to the output of said comparator switch, said first and second threshold detectors being operative to provide said step-up and stepdown signals respectively.
Claim 8
Dependent Claim
18 words
The apparatus of claim 6 wherein the first and second switching elements of said bridge are respective transistors.
Claim 9
Dependent Claim
47 words
The apparatus of claim 3 wherein said first resistance means is serially connected from said one proportionally controlled transistor to terminal B of the bridge circuit and said second resistance means is serially connected from said other proportionally controlled transistor to terminal B of the bridge circuit.
Claim 10
Dependent Claim
127 words
The apparatus of claim 3 wherein said means for applying the input control signal to said bridge switching elements comprises a zero detector including at least one signal inverting amplifier stage connected to receive the input control signal, said zero detector providing an output signal of opposite polarity to the input control signal for application to the one bridge switching element in series with the active proportionally controlled transistor to open said one switching element and another output signal of the same polarity as the input control signal for application to the other bridge switching element to close said other switching element and thereby enable current to flow through the load in one direction or the other in accordance with the polarity of the input control signal.
Claim 11
Dependent Claim
189 words
The apparatus of claim 9 wherein said means responsive to the voltage across the active proportionally controlled transistor includes a comparator switch circuit comprising a first switch serially connected with a resistor and a diode, a second switch serially connected with an additional resistor and an additional diode, said first switch being connected to be actuated by one of the output signals provided at the output of the zero detector, said second switch being connected to be actuated by the other of the output signals provided at the output of the zero detector, the junction of said resistor and said diode being connected to one of the output terminals of the bridge circuit and the junction of said additional resistor and said additional diode being connected to the other output terminal of the bridge circuit such that the active proportionally controlled transistor is disassociated with that switch of said first and second switches of the compArator switch circuit which is concurrently actuated by an output signal from the zero detector, and the side of said diodes opposite said junctions being coupled together at the output of said comparator switch.
Claim 12
Dependent Claim
137 words
The apparatus of claim 10 wherein said means responsive to the voltage across the active proportionally controlled transistor further includes a comparator comprising first and second threshold detectors each having its input connected to the output of said comparator switch, said first threshold detector normally providing a step-up signal of predetermined polarity until the signal at the comparator switch output decreases to a predetermined level whereupon the step-up signal reverses polarity and changes the voltage applied to the input terminals of the bridge to the next higher increment, and said second threshold detector normally providing a stepdown signal of predetermined polarity until the signal at the comparator switch output increases to a predetermined level whereupon the stepdown signal reverses polarity and changes the voltage applied to the input terminals of the bridge to the next lower increment.
Claim 13
Dependent Claim
51 words
The apparatus of claim 11 wherein the predetermined level of the first threshold detector is slightly greater than the saturation voltage of the active proportionally controlled transistor and the predetermined level of the second threshold detector is greater than the difference between adjacent incremental voltage levels applied to the bridge 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) | 1975-03-14 | 1975-09-13 | 1976-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-14 | 1979-09-13 | 1980-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-14 | 1983-09-13 | 1984-03-14 | $7700.00 | Window Closed / Lapsed |