US5073837A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low voltage protection circuit
Assignee: Samsung Electronics Co Ltd
•
Filing: 1989-08-10
•
Granted: 1991-12-17
•
Expires: 2009-08-10
Abstract
Abstract There is disclosed a low voltage protection circuit for preventing overdischarging in a back-up battery. The circuit includes: switching a device which supplies voltage to the load and being connected in series between the battery and load; a charging device which charges the battery by being connected in parallel to the switching device; a first control device which determines the different operation-starting and operation-terminating voltage of the battery and, at the same time, controls the "on" and "off" of the switching device by being connected in parallel to the input terminal of the battery; and a second control device which generates hysteresis voltage between the operation-starting and operation-terminating voltage by supplying the voltage which determines the operation-terminating voltage to the first control device.
Inventors
- 👤 Hoon-Kee Baek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:11
CPC Classifications
H; H02; H02J; H02J7/00; H02J7/60; H02J7/663
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
105 words
A low voltage protection circuit for preventing overdischarging of a back-up battery, said circuit comprising: switching means, for supplying a first voltage to a load, connected in series between said battery and load; charging means, for charging said battery with a second voltage, connected in parallel with said switching means; first control means, for determining different operation starting and operation-terminating voltages of said battery while said second voltage is off and controlling "on" and "off" of said switching means; connected in parallel with said battery; and second control means, for generating and supplying a voltage to said first control means for adjusting the operation-terminating voltage.
Claim 2
Dependent Claim
105 words
A low voltage protection circuit for preventing overdischarging of a back-up battery, said circuit comprising: switching means, for supplying a first voltage to a load, connected in series between said battery and load; charging means, for charging said battery with a second voltage, connected in parallel with said switching means; first control means, for determining different operation starting and operation-terminating voltages of said battery while said second voltage is off and controlling "on" and "off" of said switching means; connected in parallel with said battery; and second control means, for generating and supplying a voltage to said first control means for adjusting the operation-terminating voltage.
Claim 3
Dependent Claim
50 words
A circuit as claimed in claim 1, wherein said switching means comprises; a plurality of first transistors connected in a Darlington configuration; and a plurality of first resistors, each of said resistors being connected between an emitter and a base of a respective transistor of said plurality of first transistors.
Claim 4
Dependent Claim
108 words
A circuit as claimed in claim 1, wherein said first control means comprises: first and second resistors connected in series; a first zener diode connected between said first resistor and a positive terminal of said battery; a first transistor having a base connected to a first common connection point between said first and second resistors; a second zener diode coupled to an emitter of said first transistor; a first diode coupled between said second zener diode and a second common connection point between a negative terminal of said battery and an output terminal of said circuit; and a third resistor connected to a collector of said second transistor.
Claim 5
Dependent Claim
25 words
A circuit as claimed in claim 3, further comprising a capacitor coupled between the base of said first transistor and the second common connection point.
Claim 6
Dependent Claim
62 words
A circuit as claimed in claim 4, wherein said second control means comprises: a fourth and fifth resistors; and a third transistor having a base connected to a third common connection point between said fourth and fifth resistors, an emitter connected to the second common connection point and a collector connected to a point between said first diode and second zener diode.
Claim 7
Dependent Claim
15 words
A circuit as claimed in claim 1, wherein said charging means is a first diode.
Claim 8
Dependent Claim
24 words
A circuit as claimed in claim 2, wherein said plurality of first transistors of said switching means are activated by said first control means.
Claim 9
Independent Claim
110 words
A method of electrically preventing overdischarging of a back-up battery, comprising the steps of: charging a back-up battery; activating the back-up battery by supplying a first voltage of sufficient value to turn "ON" a first transistor; turning "ON" a switching circuit automatically upon turning "ON" of said first transistor; supplying a second voltage to a load through said switching circuit; turning "ON" and saturating a second transistor causing the first voltage supplied to said first transistor to decrease; turning "OFF" said first transistor and said switching circuit automatically upon the decrease of the first voltage to a certain level to terminate the supply of the second voltage to the load.
Claim 10
Independent Claim
110 words
A method of electrically preventing overdischarging of a back-up battery, comprising the steps of: charging a back-up battery; activating the back-up battery by supplying a first voltage of sufficient value to turn "ON" a first transistor; turning "ON" a switching circuit automatically upon turning "ON" of said first transistor; supplying a second voltage to a load through said switching circuit; turning "ON" and saturating a second transistor causing the first voltage supplied to said first transistor to decrease; turning "OFF" said first transistor and said switching circuit automatically upon the decrease of the first voltage to a certain level to terminate the supply of the second voltage to the load.
Claim 11
Dependent Claim
102 words
A low voltage protection circuit for preventing overdischarging of a back-up battery, comprising: switching means for permitting and impeding flow of a first voltage from said battery to a load; charging means, connected to parallel with said switching means, for charging said battery; first control means coupled to enable said switching means at a starting voltage; and second control means coupled to said first control means to provide a second voltage, determining a terminating voltage, to said first control means; said terminating voltage being different than said starting voltage when said switching means is enabled responsive to said primary source being off.
Claim 12
Dependent Claim
102 words
A low voltage protection circuit for preventing overdischarging of a back-up battery, comprising: switching means for permitting and impeding flow of a first voltage from said battery to a load; charging means, connected to parallel with said switching means, for charging said battery; first control means coupled to enable said switching means at a starting voltage; and second control means coupled to said first control means to provide a second voltage, determining a terminating voltage, to said first control means; said terminating voltage being different than said starting voltage when said switching means is enabled responsive to said primary source being off.
Claim 13
Dependent Claim
50 words
A circuit as claimed in claim 9, wherein said switching means comprises; a plurality of first transistors connected in a Darlington configuration; and a plurality of first resistors, each of said resistors being connected between an emitter and a base of a respective transistor of said plurality of first transistors.
Claim 14
Dependent Claim
109 words
A circuit as claimed in claim 10, wherein said first control means comprises: second and third resistors connected in series; a first zener diode connected between said second resistor and a positive input terminal of said battery; a second transistor having a base connected to a first common connection point between said second and third resistors; a second zener diode coupled to an emitter of said second transistor; a first diode coupled between said second zener diode and a second common connection point between a negative terminal of said battery and an output terminal of said circuit; and a fourth resistor connected to a collector of said second transistor.
Claim 15
Dependent Claim
25 words
A circuit as claimed in claim 11, further comprising a capacitor coupled between the base of said second transistor and the second common connection point.
Claim 16
Dependent Claim
62 words
A circuit as claimed in claim 12, wherein said second control means comprises: a plurality of fifth resistors; and a third transistor having a base connected to a third common connection point between said plurality of fifth resistors, an emitter connected to the second common connection point and a collector connected to a point between said first diode and second zener diode.
Claim 17
Dependent Claim
15 words
A circuit as claimed in claim 9, wherein said charging means is a second diode.
Claim 18
Dependent Claim
24 words
A circuit as claimed in claim 10, wherein said plurality of first transistors of said switching means are activated by said first control means.
Claim 19
Dependent Claim
128 words
A low voltage protection circuit, comprising: first terminal means for receiving energy from power source; second terminal means for receiving energy from a back-up battery; a load; switching means for supplying first voltage to said load, connected in series between said second terminal means and load; charging means, coupled to said first terminal means and connected in parallel with said switching means, for charging a battery with a second voltage from the power source; first control means, for determining different operation-starting and operation-terminating voltages of the battery when said power source is off and controlling "on" and "off" of said switching means, connectable in parallel with the battery; and second control means, for generating and supplying a voltage to said first control means for determining the operation-terminating voltage.
Claim 20
Dependent Claim
128 words
A low voltage protection circuit, comprising: first terminal means for receiving energy from power source; second terminal means for receiving energy from a back-up battery; a load; switching means for supplying first voltage to said load, connected in series between said second terminal means and load; charging means, coupled to said first terminal means and connected in parallel with said switching means, for charging a battery with a second voltage from the power source; first control means, for determining different operation-starting and operation-terminating voltages of the battery when said power source is off and controlling "on" and "off" of said switching means, connectable in parallel with the battery; and second control means, for generating and supplying a voltage to said first control means for determining the operation-terminating voltage.
Claim 21
Dependent Claim
50 words
A circuit as claimed in claim 16, wherein said switching means comprises; a plurality of first transistors connected in a Darlington configuration; and a plurality of first resistors, each of said resistors being connected between an emitter and a base of a respective transistor of said plurality of first transistors.
Claim 22
Dependent Claim
109 words
A circuit as claimed in claim 17, wherein said first control means comprises: second and third resistors connected in series; a first zener diode connected between said second resistor and a positive input terminal of said battery; a second transistor having a base connected to a first common connection point between said second and third resistors; a second zener diode coupled to an emitter of said second transistors; a first diode coupled between said second zener diode and a second common connection point between a negative terminal of said battery and an output terminal of said circuit; and a fourth resistor connected to a collector of said second transistor.
Claim 23
Dependent Claim
25 words
A circuit as claimed in claim 18, further comprising a capacitor coupled between the base of said second transistor and the second common connection point.
Claim 24
Dependent Claim
62 words
A circuit as claimed in claim 18, wherein said second control means comprises: a plurality of fifth resistors; and a third transistor having a base connected to a third common connection point between said plurality of fifth resistors, an emitter connected to the second common connection point and a collector connected to a point between said first diode and second zener diode.
Claim 25
Dependent Claim
15 words
A circuit as claimed in claim 16, wherein said charging means is a second diode.
Claim 26
Dependent Claim
24 words
A circuit as claimed in claim 17, wherein said plurality of first transistors of said switching means are activated by said first control 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) | 1994-12-16 | 1995-06-17 | 1995-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-12-16 | 1999-06-17 | 1999-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-12-16 | 2003-06-17 | 2003-12-17 | $7700.00 | Window Closed / Lapsed |