US3784893A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High voltage shutdown protection circuit with bias arrangement to decrease the voltage shutdown point with increasing load
Assignee: AT&T Inc
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Filing: 1973-01-10
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Granted: 1974-01-08
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Expires: 1993-01-10
Abstract
Abstract A current and voltage regulated DC to DC converter is designed with protection features to permit its operation in parallel with like DC to DC converters. The features are designed to assure shutdown protection against overcurrent and overvoltage conditions and to assure that each converter will contribute a current to the common load. The protection features include a selective high voltage shutdown to shut down only the converter causing an overvoltage and an overcurrent protection circuit to supersede the normal current regulation in response to a fault condition. A reverse current shutdown circuit protects the common load from faults and short circuits internal to the converter circuit. These protection features permit the converters to operate in parallel without shutting down the entire system should an individual converter malfunction.
Inventors
- 👤 R Rando
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:11
CPC Classifications
H; H02; H02H; H02H7/00; H02H7/10; H02H7/12; H02H7/1203; H02H7/1206; H02H7/1213; H02M; H02M3/00; H02M3/22; H02M3/24; H02M3/28; H02M3/305; H02M3/315; H02M3/3155
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
106 words
In a converter circuit, means to control the output of said converter comprising, means to monitor the voltage output of said converter, means to monitor the output current of said converter, voltage comparison means connected to said means to monitor the voltage output, means to establish a voltage threshold connected to said voltage comparison means, said means to establish a voltage threshold being connected to and responsive to said means to monitor the output current, and means responsive to said voltage comparison menas to disable said converter whereby the voltage threshold at which said converter is disabled is proportional to the output current of the converter.
Claim 2
Dependent Claim
106 words
In a converter circuit, means to control the output of said converter comprising, means to monitor the voltage output of said converter, means to monitor the output current of said converter, voltage comparison means connected to said means to monitor the voltage output, means to establish a voltage threshold connected to said voltage comparison means, said means to establish a voltage threshold being connected to and responsive to said means to monitor the output current, and means responsive to said voltage comparison menas to disable said converter whereby the voltage threshold at which said converter is disabled is proportional to the output current of the converter.
Claim 3
Dependent Claim
71 words
In a converter circuit as defined in claim 1 further including, means to regulate the voltage output of said converter including a regulation reference voltage source, means responsive to said means to monitor the output current to modify the voltage of the regulation reference voltage source, said means to modify the voltage of the regulation reference voltage source including threshold means to establish a current threshold at which it becomes operative.
Claim 4
Dependent Claim
133 words
In a power supply circuit a high voltage protective shutdown circuit comprising, means to monitor the voltage output of said power supply, a source of reference voltage, means to compare the voltage sensed by said means to monitor the voltage output with said reference voltage, wherein the improvement comprises, means to monitor the current output of said power supply, means to generate a bias signal proportional to the current sensed by the means to monitor the current output, means to apply said bias signal to said means to compare to alter its threshold of operation, means to utilize the output of said means to compare to shut down said power supply whereby the voltage threshold at which said shutdown circuit operates is altered in proportion to the output current of said power supply.
Claim 5
Dependent Claim
133 words
In a power supply circuit a high voltage protective shutdown circuit comprising, means to monitor the voltage output of said power supply, a source of reference voltage, means to compare the voltage sensed by said means to monitor the voltage output with said reference voltage, wherein the improvement comprises, means to monitor the current output of said power supply, means to generate a bias signal proportional to the current sensed by the means to monitor the current output, means to apply said bias signal to said means to compare to alter its threshold of operation, means to utilize the output of said means to compare to shut down said power supply whereby the voltage threshold at which said shutdown circuit operates is altered in proportion to the output current of said power supply.
Claim 6
Dependent Claim
66 words
In a power supply as defined in claim 3 further including, means to regulate the voltage output of said power supply, wherein the improvement further comprises, means responsive to said means to monitor the current output to detect low current outputs, and means to increase the voltage level at which said means to regulate regulates the output voltage upon the detection of a low current output.
Claim 7
Dependent Claim
204 words
In a DC to DC converter including a switching device, oscillatory means to drive said switching device, and output means to connect to a load to be energized wherein the improvement comprises, a high voltage protection circuit comprising a first operational amplifier connected in a high gain summing mode and having an input to establish its voltage threshold of operation, the output means of said converter being coupled to the input of said first operational amplifier, a reference voltage source connected to the input of said first operational amplifier to establish its voltage threshold, current sensing means in said output means, a second operational amplifier connected in an amplifying mode and having its input coupled to said current sensing means, the otuput of said second operational amplifier being connected to the input of said first operational amplifier to establish the voltage threshold of said first operational amplifier, and means to inhibit the operation of said oscillatory means including means to disconnect said converter from its load, the output of said first operational amplifier being connected to said means to inhibit, whereby the voltage threshold at which said first operational amplifier is responsive is proportional to the magnitude of the output current of the converter.
Claim 8
Dependent Claim
204 words
In a DC to DC converter including a switching device, oscillatory means to drive said switching device, and output means to connect to a load to be energized wherein the improvement comprises, a high voltage protection circuit comprising a first operational amplifier connected in a high gain summing mode and having an input to establish its voltage threshold of operation, the output means of said converter being coupled to the input of said first operational amplifier, a reference voltage source connected to the input of said first operational amplifier to establish its voltage threshold, current sensing means in said output means, a second operational amplifier connected in an amplifying mode and having its input coupled to said current sensing means, the otuput of said second operational amplifier being connected to the input of said first operational amplifier to establish the voltage threshold of said first operational amplifier, and means to inhibit the operation of said oscillatory means including means to disconnect said converter from its load, the output of said first operational amplifier being connected to said means to inhibit, whereby the voltage threshold at which said first operational amplifier is responsive is proportional to the magnitude of the output current of the converter.
Claim 9
Dependent Claim
135 words
A DC to DC converter as defined in claim 5 further including, a third operational amplifier connected in summing mode and having its summing input connected to said output means, means to utilize the output of said third operational amplifier to reguLate the voltage of the output means of said converter, wherein the improvement comprises, a fourth operational amplifier connected in an amplifying mode, a second reference voltage source connected to an input of said fourth operational amplifier to establish a threshold response, the output of said operational amplifier being connected to an input of said fourth operational amplifier, the output of said fourth operational amplifier being coupled to an input of said third operational amplifier wherein the regulated voltage value is modified in response to the magnitude of the current in said output means.
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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) | 1977-01-07 | 1977-07-09 | 1978-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-07 | 1981-07-09 | 1982-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-07 | 1985-07-09 | 1986-01-08 | $7700.00 | Window Closed / Lapsed |