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US3988643A Expired / Lapsed US ⏱️ 0.0 years remaining

Latch circuit

Assignee: Monroe Systems for Business Inc
•
Filing: 1974-10-25
•
Granted: 1976-10-26
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Expires: 1994-10-25
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Abstract

Abstract A Schmidt trigger voltage regulator having a latching circuit at its input to disable the regulator during an overload condition and automatically resets the latching circuit when the overload condition is removed thereby allowing the regulator to function in its normal voltage regulating mode.

Inventors

  • 👤 David Morris

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 14:00
CPC Classifications
H; H02; H02M; H02M3/00; H02M3/02; H02M3/04; H02M3/10; H02M3/145; H02M3/155; H02M3/156; H02M3/1563

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 89 words
An electrical power supply comprising: a switching voltage regulator circuit including a Schmitt trigger circuit means; and latch means, coupled to said Schmitt trigger circuit means, for turning the switching voltage regulator off when the load current exceeds a predetermined value and which automatically resets itself when the load current goes below said predetermined value, including a pair of opposite conductivity transistors, each having a base, emitter, and collector, and a diode coupled from the collector of one of said transistors to the base of the said other transistor.
Claim 2
Dependent Claim 89 words
An electrical power supply comprising: a switching voltage regulator circuit including a Schmitt trigger circuit means; and latch means, coupled to said Schmitt trigger circuit means, for turning the switching voltage regulator off when the load current exceeds a predetermined value and which automatically resets itself when the load current goes below said predetermined value, including a pair of opposite conductivity transistors, each having a base, emitter, and collector, and a diode coupled from the collector of one of said transistors to the base of the said other transistor.
Claim 3
Dependent Claim 70 words
An electric power supply according to claim 1 wherein said latch comprises: a sensing resistor, a pair of opposite conductivity transistors, each having a base, emitter, and collector, and biasing means coupled to said pair or transistors, including a first and second resistor means, the first resistor means coupled to one end of said sensing resistor and the second resistor means coupled to the other end of said sensing resistor.
Claim 4
Dependent Claim 51 words
An electric power supply according to claim 1 wherein said latch circuit comprises: a pair of opposite conductivity transistors, each having a base, emitter, and collector, and biasing means, coupled to said pair of transistors, including a third resistor means coupled between the base and emitter of one of said transistors.
Claim 5
Dependent Claim 88 words
An electric power supply according to claim 1 wherein said latch means comprises: a sensing resistor, a pair of opposite conductivity transistors, each having a base, emitter, and collector, a diode coupled from the collector of one of said transistors to the base of said other transistor, and biasing means coupled to said pair of transistors, including a first and second resistor means each coupled to one end of said sensing resistor, and a third resistor means coupled between the base and emitter of one of said transistors.

References Cited (Backward Citations)

US3078410A Cited
US3432726A Cited
US3489922A Cited
US3548220A Cited
US3582713A Cited
US3714512A Cited
US3753078A Cited
US3754182A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-10-26 1980-04-26 1980-10-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-10-26 1984-04-26 1984-10-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-10-26 1988-04-26 1988-10-26 $7700.00 Window Closed / Lapsed

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