US4405975A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Power supply start-up circuit
Assignee: General Dynamics Government Systems Corp
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Filing: 1981-10-29
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Granted: 1983-09-20
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Expires: 2001-10-29
Abstract
Abstract A power supply start-up circuit for apparatus having a storage capacitor comprises a bistable switch with a trigger terminal and connected between one terminal of a DC source and the storage capacitor, a resistor connected across the switch, a trigger capacitor connected to the trigger lead, and a diode connected between the trigger capacitor and the storage capacitor. The trigger lead on the switch is biased by the trigger capacitor which is charged through the diode to the voltage on the storage capacitor. When the storage capacitor is uncharged at start-up, the switch is biased off and charging current from the DC source to the storager capacitor passes through the resistor permitting a "soft" start, i.e., a gradual charging of the storage capacitor. Thereafter charging of the storage capacitor takes place through the switch when biased on by a voltage differential between storage and trigger capacitors.
Inventors
- 👤 Scott M. Overstreet
- 👤 C. Henning Swenson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:11
CPC Classifications
H; H02; H02M; H02M1/00; H02M1/36
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
102 words
In a power supply for electrical discharge apparatus comprising a source of DC voltage having first and second terminals and a storage capacitor connected across said terminals, a start-up circuit comprising a bistable switch having a trigger terminal, said switch being connected to said storage capacitor and to said first terminal, a shunt resistor connected across said switch, a trigger capacitor connected between said second terminal and said trigger terminal, and a diode having an anode and a cathode, said anode being connected between said storage capacitor and said switch, said cathode being connected between said trigger capacitor and said trigger electrode.
Claim 2
Dependent Claim
102 words
In a power supply for electrical discharge apparatus comprising a source of DC voltage having first and second terminals and a storage capacitor connected across said terminals, a start-up circuit comprising a bistable switch having a trigger terminal, said switch being connected to said storage capacitor and to said first terminal, a shunt resistor connected across said switch, a trigger capacitor connected between said second terminal and said trigger terminal, and a diode having an anode and a cathode, said anode being connected between said storage capacitor and said switch, said cathode being connected between said trigger capacitor and said trigger electrode.
Claim 3
Dependent Claim
17 words
The power supply according to claim 1 in which said switch is a silicon controlled rectifier (SCR).
Claim 4
Dependent Claim
33 words
The power supply according to claim 1 in which said switch has an anode and a cathode, said anode being connected to said first terminal, said cathode being connected to said storage capacitor.
Claim 5
Dependent Claim
157 words
In a power supply for electrical discharge apparatus comprising a source of DC voltage having first and second terminals and a storage capacitor connected across said terminals, a start-up circuit comprising a bistable switch having a first non-conducting state and a second conducting state and connected between said first terminal and said storage capacitor, means responsive to said DC voltage in excess of voltage on said storage capacitor during initial start-up of the power supply for maintaining said switch in said first state and thereafter changing said switch to the second state when the voltage on said storage capacitor becomes less than said DC voltage, and a shunt resistor connected across said switch, said resistor being operatively connected to and disconnected from said storage capacitor when said switch is in the first and second states, respectively, whereby said storage capacitor is initially charged from said source through said resistor and thereafter is charged only through said switch.
Claim 6
Dependent Claim
157 words
In a power supply for electrical discharge apparatus comprising a source of DC voltage having first and second terminals and a storage capacitor connected across said terminals, a start-up circuit comprising a bistable switch having a first non-conducting state and a second conducting state and connected between said first terminal and said storage capacitor, means responsive to said DC voltage in excess of voltage on said storage capacitor during initial start-up of the power supply for maintaining said switch in said first state and thereafter changing said switch to the second state when the voltage on said storage capacitor becomes less than said DC voltage, and a shunt resistor connected across said switch, said resistor being operatively connected to and disconnected from said storage capacitor when said switch is in the first and second states, respectively, whereby said storage capacitor is initially charged from said source through said resistor and thereafter is charged only through said switch.
Claim 7
Dependent Claim
41 words
The power supply according to claim 4 in which said switch comprises a silicon controlled rectifier having a trigger electrode, said electrode being responsive to said means for changing said switch from said first operating state to said second operating state.
Claim 8
Dependent Claim
172 words
In a power supply for electrical discharge apparatus comprising a source of DC voltage having first and second terminals and a storage capacitor connected across said terminals, a start-up circuit comprising a bistable switch having first and second operating states and connected between said first terminal and said storage capacitor, said switch being responsive to voltage on said storage capacitor for changing from one state to the other, and a shunt resistor connected across said switch, said resistor being operatively connected to and disconnected from said storage capacitor when said switch is in the first and second states, respectively, whereby said storage capacitor is initially charged from said source through said resistor and thereafter is charged through said switch, a diode having an anode and a cathode, said anode being connected between said switch and said storage capacitor, a trigger capacitor connected between said second terminal and the cathode of said diode, said switch being responsive to the voltage on said trigger capacitor for changing from one operating state to the other.
Claim 9
Dependent Claim
172 words
In a power supply for electrical discharge apparatus comprising a source of DC voltage having first and second terminals and a storage capacitor connected across said terminals, a start-up circuit comprising a bistable switch having first and second operating states and connected between said first terminal and said storage capacitor, said switch being responsive to voltage on said storage capacitor for changing from one state to the other, and a shunt resistor connected across said switch, said resistor being operatively connected to and disconnected from said storage capacitor when said switch is in the first and second states, respectively, whereby said storage capacitor is initially charged from said source through said resistor and thereafter is charged through said switch, a diode having an anode and a cathode, said anode being connected between said switch and said storage capacitor, a trigger capacitor connected between said second terminal and the cathode of said diode, said switch being responsive to the voltage on said trigger capacitor for changing from one operating state to the other.
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) | 1986-09-19 | 1987-03-21 | 1987-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-09-19 | 1991-03-21 | 1991-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-09-19 | 1995-03-21 | 1995-09-20 | $7700.00 | Window Closed / Lapsed |