Abstract: A charge control circuit equipped with a function of controlling a charging current to be supplied to a secondary battery, comprises: a detecting unit for monitoring a temperature; and a charge control unit for controlling so as to break the charging current when the monitored temperature rises to a temperature equal to or more than a predetermined set temperature, decrease the charging current as the monitored temperature becomes higher when the monitored temperature is in a predetermined temperature range lower than the set temperature, flow the charging current having a predetermined current value in a state where the monitored temperature is lower than a lower limit temperature of the temperature range, or flow the charging current having a current value smaller than the current value when the monitored temperature is within a range of from an upper limit temperature of the temperature range to the set temperature.

Abstract: A battery protection circuit to protect secondary batteries coupled in parallel, includes an overdischarge detection part provided for each of the secondary batteries and to output an abnormality signal when an overdischarge is detected from a corresponding one of the secondary batteries, an overcurrent detection part provided for each of the secondary batteries and to output an abnormality signal when an overcurrent is detected from a corresponding one of the secondary batteries, and a discharge control part to prohibit a discharge of at least one secondary battery when the abnormality signal is output from at least one of the overdischarge detection part and the overcurrent detection part.

Abstract: In a battery pack, an overcharge detecting circuit compares a voltage between a positive electrode and a negative electrode of a secondary battery with a threshold voltage to detect an overcharge of the secondary battery, and turns off a switching element. A series circuit including a thermistor and a resistor is arranged near the secondary battery and connected in parallel to the secondary battery. A comparator compares a voltage at a junction point of the thermistor and the resistor with a reference voltage corresponding to a predetermined temperature. In response to an output signal of the comparator, a changing unit changes the threshold voltage to a first value when a temperature of the secondary battery is below the predetermined temperature, and changes the threshold voltage to a second smaller value when the temperature of the secondary battery is above the predetermined temperature.

Abstract: In a battery pack, an overcharge detecting circuit compares a voltage between a positive electrode and a negative electrode of a secondary battery with a threshold voltage to detect an overcharge of the secondary battery, and turns off a switching element. A series circuit including a thermistor and a resistor is arranged near the secondary battery and connected in parallel to the secondary battery. A comparator compares a voltage at a junction point of the thermistor and the resistor with a reference voltage corresponding to a predetermined temperature. In response to an output signal of the comparator, a changing unit changes the threshold voltage to a first value when a temperature of the secondary battery is below the predetermined temperature, and changes the threshold voltage to a second smaller value when the temperature of the secondary battery is above the predetermined temperature.

Abstract: A battery pack including a protection circuit configured to detect over-charge, over-discharge and over-current of a rechargeable battery to turn off a switch element, the switch element provided at a wire provided between the rechargeable battery and a load circuit or a charging device; a series circuit of a thermistor and a resistor, the series circuit provided in parallel to the rechargeable battery, the thermistor thermally connected to the rechargeable battery; and an abnormal temperature detection unit provided in the protection circuit, wherein the abnormal temperature detection unit operates the switch to be in an off state when the temperature of the rechargeable battery is higher than a predetermined temperature, and when a voltage of the wire is higher than a threshold voltage of a forward drop voltage of a body diode in the switch, the abnormal temperature detection unit operates the switch to be in an on state.

Abstract: A battery pack has first through third external terminals connected to positive and negative power supply terminals and a voltage detection terminal, respectively. A secondary battery is connected between the first external terminal and the third external terminal. A protection circuit controls ON/OFF of first and second switching elements provided on a wiring between the secondary battery and a load or a charge device by detecting an overcharge, an overdischarge and an overcurrent of the secondary battery. A first thermistor is connected between the second external terminal and the third external terminal. A series circuit containing a second thermistor and a resistor is provided in parallel to the secondary battery. A third switching element is connected between the second external terminal and the third external terminal.

Abstract: A protection circuit includes a detector to detect an overcharging or an excessive discharging of a battery, from a voltage of a power terminal coupled to the battery, a controller to generate a control signal to stop the charging or the discharging of the battery when a detection of the overcharging or the excessive discharging is continuously detected by the detector for a predetermined time, and a current varying circuit to vary a current flowing through the power terminal only for a certain time when the detector detects the overcharging or the excessive discharging of the battery.

Abstract: A DC-DC converter includes: an inductance element and a rectifier element connected in series between a voltage input terminal to accept input direct current voltage and a first output terminal; a switching element connected between a connection node of the inductance element and the rectifier element and a reference potential point; and a controlling circuit to form a signal to control on/off of the switching element. The controlling circuit controls on/off of the switching element to control current through the inductance element, and a voltage applied to the voltage input terminal to accept the input direct current voltage is output via a second output terminal as a reference potential of a circuit at a latter stage, so that an output voltage is controllable from a lower to higher voltage than the input direct current voltage without switching step-up and step-down operations.

Abstract: A disclosed timer circuit for clocking a predetermined time includes an oscillator and a frequency dividing unit for dividing a frequency of an oscillating signal output from the oscillator. A comparing unit determines whether a short-time mode instruction is received by comparing a voltage received at an external terminal with a predetermined voltage. A switch causes the oscillating signal to bypass a part of the frequency dividing unit in response receiving the short-time mode instruction.

Abstract: A battery pack has first through third external terminals connected to positive and negative power supply terminals and a voltage detection terminal, respectively. A secondary battery is connected between the first external terminal and the third external terminal. A protection circuit controls ON/OFF of first and second switching elements provided on a wiring between the secondary battery and a load or a charge device by detecting an overcharge, an overdischarge and an overcurrent of the secondary battery. A first thermistor is connected between the second external terminal and the third external terminal. A series circuit containing a second thermistor and a resistor is provided in parallel to the secondary battery. A third switching element is connected between the second external terminal and the third external terminal.

Abstract: A power circuit is disclosed which is connected to a power source supplying different currents. The power circuit supplying driving power from the power source to a load includes a switching unit configured to switch the driving power supplied to the load in response to an external switching signal.

Abstract: A charge control circuit equipped with a function of controlling a charging current to be supplied to a secondary battery, comprises: a detecting unit for monitoring a temperature; and a charge control unit for controlling so as to break the charging current when the monitored temperature rises to a temperature equal to or more than a predetermined set temperature, decrease the charging current as the monitored temperature becomes higher when the monitored temperature is in a predetermined temperature range lower than the set temperature, flow the charging current having a predetermined current value in a state where the monitored temperature is lower than a lower limit temperature of the temperature range, or flow the charging current having a current value smaller than the current value when the monitored temperature is within a range of from an upper limit temperature of the temperature range to the set temperature.

Abstract: A battery pack including a protection circuit configured to detect over-charge, over-discharge and over-current of a rechargeable battery to turn off a switch element, the switch element provided at a wire provided between the rechargeable battery and a load circuit or a charging device; a series circuit of a thermistor and a resistor, the series circuit provided in parallel to the rechargeable battery, the thermistor thermally connected to the rechargeable battery; and an abnormal temperature detection unit provided in the protection circuit, wherein the abnormal temperature detection unit operates the switch to be in an off state when the temperature of the rechargeable battery is higher than a predetermined temperature, and when a voltage of the wire is higher than a threshold voltage of a forward drop voltage of a body diode in the switch, the abnormal temperature detection unit operates the switch to be in an on state.

Abstract: In a battery pack, an overcharge detecting circuit compares a voltage between a positive electrode and a negative electrode of a secondary battery with a threshold voltage to detect an overcharge of the secondary battery, and turns off a switching element. A series circuit including a thermistor and a resistor is arranged near the secondary battery and connected in parallel to the secondary battery. A comparator compares a voltage at a junction point of the thermistor and the resistor with a reference voltage corresponding to a predetermined temperature. In response to an output signal of the comparator, a changing unit changes the threshold voltage to a first value when a temperature of the secondary battery is below the predetermined temperature, and changes the threshold voltage to a second smaller value when the temperature of the secondary battery is above the predetermined temperature.

Abstract: A power supply control circuit is disclosed. The power supply control circuit controls a current which is supplied from a power source to a load. The power supply control circuit includes a reverse current detecting circuit which detects a reverse current flowing from the load to the power source and a reverse current preventing circuit which disconnects a line between the power source and the load when the reverse current is detected by the reverse current detecting circuit.

Abstract: Disclosed is a DC-DC converter including: an inductance element and a rectifier element connected in series between a voltage input terminal to accept input direct current voltage and a first output terminal; a switching element connected between a connection node of the inductance element and the rectifier element and a reference potential point; and a controlling circuit to form a signal to control on/off of the switching element, wherein the controlling circuit controls on/off of the switching element to control current through the inductance element and a voltage applied to the voltage input terminal to accept the input direct current voltage is output to a second output terminal as a reference potential of a circuit at a latter stage, so that an output voltage is controllable from a lower to higher voltage than the input direct current voltage without switching step-up and step-down operations.

Abstract: A disclosed timer circuit for clocking a predetermined time includes an oscillator and a frequency dividing unit for dividing a frequency of an oscillating signal output from the oscillator. A comparing unit determines whether a short-time mode instruction is received by comparing a voltage received at an external terminal with a predetermined voltage. A switch causes the oscillating signal to bypass a part of the frequency dividing unit in response receiving the short-time mode instruction.

Abstract: A power supply circuit is disclosed that includes a coil with first and second ends having supply voltage applied to the first end, a first switching element connected between the second end of the coil and ground, a second switching or diode element supplying current to a load after rectifying the current in accordance with voltage generated at the connection of the coil and the first switching element, a driver circuit switching at least the first switching element, a third switching element connected in series to the load, and a power supply stop circuit switching off the first element so as to stop supplying power to the load and switching off the third element so as to stop supplying the current to the load in accordance with an external signal.

Abstract: A power supply control circuit is disclosed. The power supply control circuit controls a current which is supplied from a power source to a load. The power supply control circuit includes a reverse current detecting circuit which detects a reverse current flowing from the load to the power source and a reverse current preventing circuit which disconnects a line between the power source and the load when the reverse current is detected by the reverse current detecting circuit.

Abstract: A power circuit is disclosed which is connected to a power source supplying different currents. The power circuit supplying driving power from the power source to a load includes a switching unit configured to switch the driving power supplied to the load in response to an external switching signal.