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US5721480A Expired / Lapsed US ⏱️ 0.0 years remaining

System and method for controlling charging of secondary battery that requires constant-voltage charge control

Assignee: Toshiba Corp
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Filing: 1997-01-29
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Granted: 1998-02-24
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Expires: 2017-01-29
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Abstract

Abstract In a system for charging a rechargeable battery with constant voltage, a power supply supplies a voltage increased with time. An overvoltage generating circuit outputs an overvoltage signal for a first predetermined period when a supplied voltage to the rechargeable battery exceed a reference voltage. In response to the overvoltage signal from the overvoltage generating circuit, a multivibrator gradually drops the voltage from the power supply for a second predetermined period being longer than the first period. A sample/hold circuit holds the voltage from the power supply when a control signal is not supplied, and samples the voltage from the power supply when the control signal is supplied. A comparator compares the voltage from the power supply with a held voltage of the sample/hold circuit, and generates a signal when the voltage from the power supply is higher than the held voltage of the sample/hold circuit. A logical sum circuit supplies the control signal to the sample/hold circuit in response to the signal from the comparator or the overvoltage signal from the overvoltage generating circuit. A voltage follower supplies the held or the sampled voltage from the sample/hold circuit to the rechargeable battery.

Inventors

  • 👤 Shizuo Morioka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 10:22
CPC Classifications
H; H02; H02J; H02J7/00; H02J7/40; H02J7/44; H02J7/485

Claims Analysis

Total Claims: 42
Claim 1
Independent Claim 147 words
A system for charging a device with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; and means for holding the voltage from the supplying means when the voltage from the supplying means is lower than a held voltage and the overvoltage signal is not output from the outputting means, and sampling the voltage from the supplying means when the voltage from the supplying means is higher than the held voltage or the overvoltage signal is output from the outputting means, the held or the sampled voltage being supplied to the device.
Claim 2
Independent Claim 147 words
A system for charging a device with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; and means for holding the voltage from the supplying means when the voltage from the supplying means is lower than a held voltage and the overvoltage signal is not output from the outputting means, and sampling the voltage from the supplying means when the voltage from the supplying means is higher than the held voltage or the overvoltage signal is output from the outputting means, the held or the sampled voltage being supplied to the device.
Claim 3
Dependent Claim 13 words
The system according to claim 1, wherein the device is a rechargeable battery.
Claim 4
Dependent Claim 14 words
The system according to claim 2, further comprising a pack housing the rechargeable battery.
Claim 5
Dependent Claim 15 words
The system according to claim 3, wherein the output means is built in the pack.
Claim 6
Dependent Claim 13 words
The system according to claim 1, wherein the dropping means includes a multivibrator.
Claim 7
Dependent Claim 19 words
The system according to claim 5, wherein the multivibrator and the holding/sampling means are built in one integrated circuit.
Claim 8
Independent Claim 172 words
A system for charging a device with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; means for holding the voltage from the supplying means when the voltage from the supplying means is lower than a held voltage and the overvoltage signal is not output from the outputting means, and sampling the voltage from the supplying means when the voltage from the supplying means is higher than the held voltage or the overvoltage signal is output from the outputting means; means for limiting the held or the sampled voltage from the sampling and holding means to a predetermined value; and means for supplying a current corresponding to the voltage limited by the limiting means to the device.
Claim 9
Independent Claim 172 words
A system for charging a device with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; means for holding the voltage from the supplying means when the voltage from the supplying means is lower than a held voltage and the overvoltage signal is not output from the outputting means, and sampling the voltage from the supplying means when the voltage from the supplying means is higher than the held voltage or the overvoltage signal is output from the outputting means; means for limiting the held or the sampled voltage from the sampling and holding means to a predetermined value; and means for supplying a current corresponding to the voltage limited by the limiting means to the device.
Claim 10
Dependent Claim 13 words
The system according to claim 7, wherein the device is a rechargeable battery.
Claim 11
Dependent Claim 14 words
The system according to claim 8, further comprising a pack housing the rechargeable battery.
Claim 12
Dependent Claim 15 words
The system according to claim 9, wherein the output means is built in the pack.
Claim 13
Dependent Claim 13 words
The system according to claim 7, wherein the dropping means includes a multivibrator.
Claim 14
Dependent Claim 19 words
The system according to claim 11, wherein the multivibrator and the holding/sampling means are built in one integrated circuit.
Claim 15
Independent Claim 192 words
A system for charging a rechargeable battery with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; means for holding the voltage from the supplying means when a control signal is not supplied, and sampling the voltage from the supplying means when the control signal is supplied; means for comparing the voltage from the supplying means with a held voltage of the sampling and holding means, and generating a signal when the voltage from the supplying means is higher than the held voltage from the sampling and holding means; means for supplying the control signal to the sampling and holding means in response to the signal from the comparing means or the overvoltage signal from the outputting means; and means for supplying the held or the sampled voltage from the sampling and holding means to the device.
Claim 16
Independent Claim 192 words
A system for charging a rechargeable battery with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; means for holding the voltage from the supplying means when a control signal is not supplied, and sampling the voltage from the supplying means when the control signal is supplied; means for comparing the voltage from the supplying means with a held voltage of the sampling and holding means, and generating a signal when the voltage from the supplying means is higher than the held voltage from the sampling and holding means; means for supplying the control signal to the sampling and holding means in response to the signal from the comparing means or the overvoltage signal from the outputting means; and means for supplying the held or the sampled voltage from the sampling and holding means to the device.
Claim 17
Independent Claim 189 words
A system for charging a rechargeable battery with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; first and second voltage follower means, connected in parallel to each other, for holding the voltage from the supplying means; rectifier means, connected in series with the first voltage follower means, capable of being turned on when the voltage from the first voltage follower means exceeds a predetermined voltage; switch means, connected in series with the second voltage follower means, capable of being turned on in response to the overvoltage signal from the outputting means; capacitor means, connected to the rectifier means and switch means, capable of being charged when the switch means is off and being discharged when the switch means is on; and means for supplying the voltage from the capacitor means to the device.
Claim 18
Independent Claim 189 words
A system for charging a rechargeable battery with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; first and second voltage follower means, connected in parallel to each other, for holding the voltage from the supplying means; rectifier means, connected in series with the first voltage follower means, capable of being turned on when the voltage from the first voltage follower means exceeds a predetermined voltage; switch means, connected in series with the second voltage follower means, capable of being turned on in response to the overvoltage signal from the outputting means; capacitor means, connected to the rectifier means and switch means, capable of being charged when the switch means is off and being discharged when the switch means is on; and means for supplying the voltage from the capacitor means to the device.
Claim 19
Independent Claim 196 words
A system for charging a rechargeable battery with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; first and second rectifier means, connected in inverse-parallel to each other, the first rectifier means capable of being turned on when the voltage from the supplying means exceeds a first predetermined voltage, and the second rectifier means capable of being turned on when the voltage from the supplying means falls below a second predetermined voltage; switch means, connected in series with the second rectifier means, capable of being turned on in response to the overvoltage signal from the outputting means; capacitor means, connected to the first rectifier means and the switch means, capable of being charged when the switch means is off and being discharged when the switch means is on; and means for supplying the voltage from the capacitor means to the device.
Claim 20
Independent Claim 196 words
A system for charging a rechargeable battery with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; first and second rectifier means, connected in inverse-parallel to each other, the first rectifier means capable of being turned on when the voltage from the supplying means exceeds a first predetermined voltage, and the second rectifier means capable of being turned on when the voltage from the supplying means falls below a second predetermined voltage; switch means, connected in series with the second rectifier means, capable of being turned on in response to the overvoltage signal from the outputting means; capacitor means, connected to the first rectifier means and the switch means, capable of being charged when the switch means is off and being discharged when the switch means is on; and means for supplying the voltage from the capacitor means to the device.
Claim 21
Independent Claim 210 words
A system for charging a rechargeable battery with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; means for holding the voltage from the supplying means when a control signal is not supplied, and sampling the voltage from the supplying means when the control signal is supplied; means for comparing the voltage from the supplying means with a held voltage of the sampling and holding means, and generating a signal when the voltage from the supplying means is higher than the held voltage of the sampling and holding means; means for supplying the control signal to the sampling and holding means in response to the signal from the comparing means or the overvoltage signal from the outputting means; means for limiting the held or the sampled voltage from the sampling and holding means to a predetermined value; and means for supplying a current corresponding to the voltage limited by the limiting means to the device.
Claim 22
Independent Claim 210 words
A system for charging a rechargeable battery with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; means for holding the voltage from the supplying means when a control signal is not supplied, and sampling the voltage from the supplying means when the control signal is supplied; means for comparing the voltage from the supplying means with a held voltage of the sampling and holding means, and generating a signal when the voltage from the supplying means is higher than the held voltage of the sampling and holding means; means for supplying the control signal to the sampling and holding means in response to the signal from the comparing means or the overvoltage signal from the outputting means; means for limiting the held or the sampled voltage from the sampling and holding means to a predetermined value; and means for supplying a current corresponding to the voltage limited by the limiting means to the device.
Claim 23
Independent Claim 207 words
A system for charging a rechargeable battery with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; first and second voltage follower means, connected in parallel to each other, for holding the voltage from the supplying means; rectifier means, connected in series with the first voltage follower means, capable of being turned on when the voltage from the first voltage follower means exceeds a predetermined voltage; switch means, connected in series with the second voltage follower means, capable of being turned on in response to the overvoltage signal from the outputting means; capacitor means, connected to the rectifier means and switch means, capable of being charged when the switch means is off and being discharged when the switch means is on; means for limiting the voltage from the capacitor means to a predetermined value; and means for supplying a current corresponding to the voltage limited by the limiting means to the device.
Claim 24
Independent Claim 207 words
A system for charging a rechargeable battery with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; first and second voltage follower means, connected in parallel to each other, for holding the voltage from the supplying means; rectifier means, connected in series with the first voltage follower means, capable of being turned on when the voltage from the first voltage follower means exceeds a predetermined voltage; switch means, connected in series with the second voltage follower means, capable of being turned on in response to the overvoltage signal from the outputting means; capacitor means, connected to the rectifier means and switch means, capable of being charged when the switch means is off and being discharged when the switch means is on; means for limiting the voltage from the capacitor means to a predetermined value; and means for supplying a current corresponding to the voltage limited by the limiting means to the device.
Claim 25
Independent Claim 214 words
A system for charging a rechargeable battery with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; first and second rectifier means, connected in inverse-parallel to each other, the first rectifier means capable of being turned on when the voltage from the supplying means exceeds a first predetermined voltage, and the second rectifier means capable of being turned on when the voltage from the supplying means falls below a second predetermined voltage; switch means, connected in series with the second rectifier means, capable of being turned on in response to the overvoltage signal from the outputting means; capacitor means, connected to the first rectifier means and the switch means, capable of being charged when the switch means is off and being discharged when the switch means is on; means for limiting the voltage from the capacitor means to a predetermined value; and means for supplying a current corresponding to the voltage limited by the limiting means to the device.
Claim 26
Independent Claim 214 words
A system for charging a rechargeable battery with constant voltage, comprising: means for supplying a voltage increased with time; means for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the device exceed a reference voltage; means, in response to the overvoltage signal from the outputting means, for gradually dropping the voltage from the supplying means for a second predetermined period being longer than the first period; first and second rectifier means, connected in inverse-parallel to each other, the first rectifier means capable of being turned on when the voltage from the supplying means exceeds a first predetermined voltage, and the second rectifier means capable of being turned on when the voltage from the supplying means falls below a second predetermined voltage; switch means, connected in series with the second rectifier means, capable of being turned on in response to the overvoltage signal from the outputting means; capacitor means, connected to the first rectifier means and the switch means, capable of being charged when the switch means is off and being discharged when the switch means is on; means for limiting the voltage from the capacitor means to a predetermined value; and means for supplying a current corresponding to the voltage limited by the limiting means to the device.
Claim 27
Independent Claim 201 words
A system for charging a rechargeable battery with constant voltage, comprising: a power supply for supplying a voltage increased with time; an overvoltage generating circuit for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the rechargeable battery exceed a reference voltage; a multivibrator, in response to the overvoltage signal from the overvoltage generating circuit, for gradually dropping the voltage from the power supply for a second predetermined period being longer than the first period; a sample/hold circuit for holding the voltage from the power supply when a control signal is not supplied, and sampling the voltage from the power supply when the control signal is supplied; a comparator for comparing the voltage from the power supply with a held voltage of the sample/hold circuit, and generating a signal when the voltage from the power supply is higher than the held voltage of the sample/hold circuit; a logical sum circuit for supplying the control signal to the sample/hold circuit in response to the signal from the comparator or the overvoltage signal from the overvoltage generating circuit; and a voltage follower for supplying the held or the sampled voltage from the sample/hold circuit to the rechargeable battery.
Claim 28
Independent Claim 201 words
A system for charging a rechargeable battery with constant voltage, comprising: a power supply for supplying a voltage increased with time; an overvoltage generating circuit for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the rechargeable battery exceed a reference voltage; a multivibrator, in response to the overvoltage signal from the overvoltage generating circuit, for gradually dropping the voltage from the power supply for a second predetermined period being longer than the first period; a sample/hold circuit for holding the voltage from the power supply when a control signal is not supplied, and sampling the voltage from the power supply when the control signal is supplied; a comparator for comparing the voltage from the power supply with a held voltage of the sample/hold circuit, and generating a signal when the voltage from the power supply is higher than the held voltage of the sample/hold circuit; a logical sum circuit for supplying the control signal to the sample/hold circuit in response to the signal from the comparator or the overvoltage signal from the overvoltage generating circuit; and a voltage follower for supplying the held or the sampled voltage from the sample/hold circuit to the rechargeable battery.
Claim 29
Independent Claim 192 words
A system for charging a rechargeable battery with constant voltage, comprising: a power supply for supplying a voltage increased with time; an overvoltage generating circuit for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the rechargeable battery exceed a reference voltage; a multivibrator, in response to the overvoltage signal from the overvoltage generating circuit, for gradually dropping the voltage from the power supply for a second predetermined period being longer than the first period; first and second voltage followers, connected in parallel to each other, for holding the voltage from the power supply; a diode, connected in series with the first voltage follower, capable of being turned on when the voltage from the first voltage follower exceeds a predetermined voltage; a switch, connected in series with the second voltage follower, capable of being turned on in response to the overvoltage signal from the overvoltage generating circuit; a capacitor, connected to the diode and switch, capable of being charged when the switch is off and being discharged when the switch is on; and a voltage follower for supplying the voltage from the capacitor to the rechargeable battery.
Claim 30
Independent Claim 192 words
A system for charging a rechargeable battery with constant voltage, comprising: a power supply for supplying a voltage increased with time; an overvoltage generating circuit for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the rechargeable battery exceed a reference voltage; a multivibrator, in response to the overvoltage signal from the overvoltage generating circuit, for gradually dropping the voltage from the power supply for a second predetermined period being longer than the first period; first and second voltage followers, connected in parallel to each other, for holding the voltage from the power supply; a diode, connected in series with the first voltage follower, capable of being turned on when the voltage from the first voltage follower exceeds a predetermined voltage; a switch, connected in series with the second voltage follower, capable of being turned on in response to the overvoltage signal from the overvoltage generating circuit; a capacitor, connected to the diode and switch, capable of being charged when the switch is off and being discharged when the switch is on; and a voltage follower for supplying the voltage from the capacitor to the rechargeable battery.
Claim 31
Independent Claim 199 words
A system for charging a rechargeable battery with constant voltage, comprising: a power supply for supplying a voltage increased with time; an overvoltage generating circuit for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the rechargeable battery exceed a reference voltage; a multivibrator, in response to the overvoltage signal from the overvoltage generating circuit, for gradually dropping the voltage from the power supply for a second predetermined period being longer than the first period; first and second diodes, connected in inverse-parallel to each other, the first diode capable of being turned on when the voltage from the power supply exceeds a first predetermined voltage, and the second diode capable of being turned on when the voltage from the power supply falls below a second predetermined voltage; a switch, connected in series with the second diode, capable of being turned on in response to the overvoltage signal from the overvoltage generating circuit; a capacitor, connected to the first diode and the switch, capable of being charged when the switch is off and being discharged when the switch is on; and a voltage follower for supplying the voltage from the capacitor to the rechargeable battery.
Claim 32
Independent Claim 199 words
A system for charging a rechargeable battery with constant voltage, comprising: a power supply for supplying a voltage increased with time; an overvoltage generating circuit for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the rechargeable battery exceed a reference voltage; a multivibrator, in response to the overvoltage signal from the overvoltage generating circuit, for gradually dropping the voltage from the power supply for a second predetermined period being longer than the first period; first and second diodes, connected in inverse-parallel to each other, the first diode capable of being turned on when the voltage from the power supply exceeds a first predetermined voltage, and the second diode capable of being turned on when the voltage from the power supply falls below a second predetermined voltage; a switch, connected in series with the second diode, capable of being turned on in response to the overvoltage signal from the overvoltage generating circuit; a capacitor, connected to the first diode and the switch, capable of being charged when the switch is off and being discharged when the switch is on; and a voltage follower for supplying the voltage from the capacitor to the rechargeable battery.
Claim 33
Independent Claim 222 words
A system for charging a rechargeable battery with constant voltage, comprising: a power supply for supplying a voltage increased with time; an overvoltage generating circuit for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the rechargeable battery exceed a reference voltage; a multivibrator, in response to the overvoltage signal from the overvoltage generating circuit, for gradually dropping the voltage from the power supply for a second predetermined period being longer than the first period; a sample/hold circuit for holding the voltage from the power supply when a control signal is not supplied, and sampling the voltage from the power supply when the control signal is supplied; a comparator for comparing the voltage from the power supply with a held voltage of the sample/hold circuit, and generating a signal when the voltage from the power supply is higher than the held voltage of the sample/hold circuit; a logical sum circuit for supplying the control signal to the sample/hold circuit in response to the signal from the comparator or the overvoltage signal from the overvoltage generating circuit; a zener diode for limiting the held or the sampled voltage from the sample/hold circuit to a predetermined value; and a constant current circuit for supplying a current corresponding to the voltage limited by the zener diode to the rechargeable battery.
Claim 34
Independent Claim 222 words
A system for charging a rechargeable battery with constant voltage, comprising: a power supply for supplying a voltage increased with time; an overvoltage generating circuit for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the rechargeable battery exceed a reference voltage; a multivibrator, in response to the overvoltage signal from the overvoltage generating circuit, for gradually dropping the voltage from the power supply for a second predetermined period being longer than the first period; a sample/hold circuit for holding the voltage from the power supply when a control signal is not supplied, and sampling the voltage from the power supply when the control signal is supplied; a comparator for comparing the voltage from the power supply with a held voltage of the sample/hold circuit, and generating a signal when the voltage from the power supply is higher than the held voltage of the sample/hold circuit; a logical sum circuit for supplying the control signal to the sample/hold circuit in response to the signal from the comparator or the overvoltage signal from the overvoltage generating circuit; a zener diode for limiting the held or the sampled voltage from the sample/hold circuit to a predetermined value; and a constant current circuit for supplying a current corresponding to the voltage limited by the zener diode to the rechargeable battery.
Claim 35
Independent Claim 213 words
A system for charging a rechargeable battery with constant voltage, comprising: a power supply for supplying a voltage increased with time; an overvoltage generating circuit for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the rechargeable battery exceed a reference voltage; a multivibrator, in response to the overvoltage signal from the overvoltage generating circuit, for gradually dropping the voltage from the power supply for a second predetermined period being longer than the first period; first and second voltage followers, connected in parallel to each other, for holding the voltage from the power supply; a diode, connected in series with the first voltage follower, capable of being turned on when the voltage from the first voltage follower exceeds a predetermined voltage; a switch, connected in series with the second voltage follower, capable of being turned on in response to the overvoltage signal from the overvoltage generating circuit; a capacitor, connected to the diode and switch, capable of being charged when the switch is off and being discharged when the switch is on; a zener diode for limiting the voltage from the capacitor to a predetermined value; and a constant current circuit for supplying a current corresponding to the voltage limited by the zener diode to the rechargeable battery.
Claim 36
Independent Claim 213 words
A system for charging a rechargeable battery with constant voltage, comprising: a power supply for supplying a voltage increased with time; an overvoltage generating circuit for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the rechargeable battery exceed a reference voltage; a multivibrator, in response to the overvoltage signal from the overvoltage generating circuit, for gradually dropping the voltage from the power supply for a second predetermined period being longer than the first period; first and second voltage followers, connected in parallel to each other, for holding the voltage from the power supply; a diode, connected in series with the first voltage follower, capable of being turned on when the voltage from the first voltage follower exceeds a predetermined voltage; a switch, connected in series with the second voltage follower, capable of being turned on in response to the overvoltage signal from the overvoltage generating circuit; a capacitor, connected to the diode and switch, capable of being charged when the switch is off and being discharged when the switch is on; a zener diode for limiting the voltage from the capacitor to a predetermined value; and a constant current circuit for supplying a current corresponding to the voltage limited by the zener diode to the rechargeable battery.
Claim 37
Independent Claim 220 words
A system for charging a rechargeable battery with constant voltage, comprising: a power supply for supplying a voltage increased with time; an overvoltage generating circuit for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the rechargeable battery exceed a reference voltage; a multivibrator, in response to the overvoltage signal from the overvoltage generating circuit, for gradually dropping the voltage from the power supply for a second predetermined period being longer than the first period; first and second diodes, connected in inverse-parallel to each other, the first diode capable of being turned on when the voltage from the power supply exceeds a first predetermined voltage, and the second diode capable of being turned on when the voltage from the power supply falls below a second predetermined voltage; a switch, connected in series with the second diode, capable of being turned on in response to the overvoltage signal from the overvoltage generating circuit; a capacitor, connected to the first diode and the switch, capable of being charged when the switch is off and being discharged when the switch is on; a zener diode for limiting the voltage from the capacitor to a predetermined value; and a constant current circuit for supplying a current corresponding to the voltage limited by the zener diode to the rechargeable battery.
Claim 38
Independent Claim 220 words
A system for charging a rechargeable battery with constant voltage, comprising: a power supply for supplying a voltage increased with time; an overvoltage generating circuit for outputting an overvoltage signal for a first predetermined period when a supplied voltage to the rechargeable battery exceed a reference voltage; a multivibrator, in response to the overvoltage signal from the overvoltage generating circuit, for gradually dropping the voltage from the power supply for a second predetermined period being longer than the first period; first and second diodes, connected in inverse-parallel to each other, the first diode capable of being turned on when the voltage from the power supply exceeds a first predetermined voltage, and the second diode capable of being turned on when the voltage from the power supply falls below a second predetermined voltage; a switch, connected in series with the second diode, capable of being turned on in response to the overvoltage signal from the overvoltage generating circuit; a capacitor, connected to the first diode and the switch, capable of being charged when the switch is off and being discharged when the switch is on; a zener diode for limiting the voltage from the capacitor to a predetermined value; and a constant current circuit for supplying a current corresponding to the voltage limited by the zener diode to the rechargeable battery.
Claim 39
Independent Claim 151 words
A method of charging a battery with a constant voltage used for a system comprising a power supply supplying a voltage and a sample/hold circuit sampling or holding the voltage, the method comprising the steps of: gradually increasing the voltage from the power supply with time; sampling the increased voltage, the increased voltage being supplied to the battery; outputting an overvoltage signal for a first predetermined period when the increased voltage is higher than a reference voltage; gradually dropping the voltage from the power supply for a second predetermined period being longer than the first predetermined period in response to the overvoltage signal, the voltage from the power supply being increased when the second period is elapsed; sampling the dropped voltage for the first period, the dropped voltage being supplied to the battery; and holding a voltage when the first period is elapsed, the held voltage being supplied to the battery.
Claim 40
Independent Claim 151 words
A method of charging a battery with a constant voltage used for a system comprising a power supply supplying a voltage and a sample/hold circuit sampling or holding the voltage, the method comprising the steps of: gradually increasing the voltage from the power supply with time; sampling the increased voltage, the increased voltage being supplied to the battery; outputting an overvoltage signal for a first predetermined period when the increased voltage is higher than a reference voltage; gradually dropping the voltage from the power supply for a second predetermined period being longer than the first predetermined period in response to the overvoltage signal, the voltage from the power supply being increased when the second period is elapsed; sampling the dropped voltage for the first period, the dropped voltage being supplied to the battery; and holding a voltage when the first period is elapsed, the held voltage being supplied to the battery.
Claim 41
Independent Claim 187 words
A method of charging a battery with a constant voltage used for a system comprising a power supply supplying a voltage and a sample/hold circuit sampling or holding the voltage, the method comprising the steps of: gradually increasing the voltage from the power supply with time; sampling the increased voltage; limiting the sampled voltage to a predetermined value, a current corresponding to the limited being supplied to the battery; outputting an overvoltage signal for a first predetermined period when the voltage supplied to the battery is higher than a reference voltage; gradually dropping the voltage from the power supply for a second predetermined period being longer than the first predetermined period in response to the overvoltage signal, the voltage from the power supply being increased when the second period is elapsed; sampling the dropped voltage for the first period; limiting the sampled voltage to a predetermined value, a current corresponding to the limited being supplied to the battery; holding a voltage when the first period is elapsed; and limiting the held voltage to a predetermined value, a current corresponding to the limited being supplied to the battery.
Claim 42
Independent Claim 187 words
A method of charging a battery with a constant voltage used for a system comprising a power supply supplying a voltage and a sample/hold circuit sampling or holding the voltage, the method comprising the steps of: gradually increasing the voltage from the power supply with time; sampling the increased voltage; limiting the sampled voltage to a predetermined value, a current corresponding to the limited being supplied to the battery; outputting an overvoltage signal for a first predetermined period when the voltage supplied to the battery is higher than a reference voltage; gradually dropping the voltage from the power supply for a second predetermined period being longer than the first predetermined period in response to the overvoltage signal, the voltage from the power supply being increased when the second period is elapsed; sampling the dropped voltage for the first period; limiting the sampled voltage to a predetermined value, a current corresponding to the limited being supplied to the battery; holding a voltage when the first period is elapsed; and limiting the held voltage to a predetermined value, a current corresponding to the limited being supplied to the battery.

References Cited (Backward Citations)

US5581772A Cited
US5397979A Cited
US5617007A Cited

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