Abstract: An overcharge detecting comparator (121) detects an overcharged state of a battery (101), and an overcurrent detecting comparator (120) detects an overcurrent state of the battery (101). In response to output signals from those comparators, a control circuit (210) performs on/off control of each of a switch (102) and a protection circuit (50). In response to an output signal from the control circuit (210), the protection circuit (50) is turned on, to thereby connect a resistor (125) to a path connecting a VSS terminal and an overcurrent detecting terminal, and is turned off, to thereby disconnect the resistor (125) from the path. As a result, even when the battery is in the overcurrent state, current consumption can be reduced.

Abstract: A charge and discharge control circuit which accommodates pulsed charge and pulsed discharge and can control charge and discharge of a secondary battery with safety, and a rechargeable power supply device having the same built therein are provided. The charge and discharge control circuit includes a delay time switching circuit for shortening a delay time of overcharge detection after charge inhibition is canceled. When overcharge is detected after the charge inhibition is canceled, the charge is inhibited in a delay time which is shorter than a normal delay time of the overcharge detection.

Abstract: Provided are a battery state monitoring circuit and a battery device that are capable of reliably controlling charge by a charger even if a voltage of a secondary battery drops to around 0 V. In the battery device provided with the battery state monitoring circuit, respective gate voltages of a P-type metal oxide semiconductor (PMOS) transistor and an N-type metal oxide semiconductor (NMOS) transistor, which together form a voltage detection circuit for detecting a voltage of around 0 V of the secondary battery, are applied by a voltage dividing resistor circuit that is connected across terminals of the secondary battery.

Abstract: Provided are a charge/discharge control circuit and a charging type power supply device which include an intermediate terminal disconnection detection circuit having low current consumption. In the charge/discharge control circuit, a constant current circuit serving as an intermediate terminal disconnection detection circuit is provided to a terminal to which secondary batteries are connected, and includes a depletion type metal oxide semiconductor (MOS) transistor and a resistor connected between a gate terminal and a source terminal of the depletion type MOS transistor.

Abstract: Provided are a battery state monitoring circuit and a battery device which can be readily adapted to variation in number of batteries, and has low withstand voltage and a simple circuit configuration.

Abstract: An object of the present invention is to provide a battery state monitoring circuit and a battery device which are capable of normally operating when a charger (301) is connected to an opposite polarity in error, and then correctly connected. In the case where the charger (301) is connected to the opposite polarity in error and then correctly connected, a logic circuit (305) does not output a power-down signal that powers down the respective circuits to the respective circuits by the aid of a power-down preventing circuit (110). As a result, the battery device normally operates without falling into the power-down state.

Abstract: Provided are a battery state monitoring circuit and a battery device which are capable of inhibiting discharge without enabling an overdischarge cell balance function when an overcurrent detection circuit detects a discharge overcurrent, without the need for an additional terminal of the battery state monitoring circuit. A detection signal of the overcurrent detection circuit is input to each of a communication terminal for overdischarge signal and a communication terminal for overcharge signal included in the battery state monitoring circuit provided on a side of the overcurrent detection circuit. An overdischarge cell balance circuit outputs a cell balance signal when an overdischarge detection signal indicates an overdischarge non-detected state, an overdischarge signal indicates an overdischarge detected state, and an overcharge signal indicates an overcharge non-detected state.

Abstract: Provided is a charging and discharging protection circuit realizing low current consumption in an overcurrent detection state, easy calculation of an automatic return impedance, and high usability. A pull-down circuit for pulling down an overcurrent detection terminal to a VSS terminal is connected in series between the overcurrent detection terminal and a switching circuit. The switching circuit is connected in series between the pull-down circuit and the VSS terminal.

Abstract: Provided is a charge/discharge protection circuit, which has a simple circuit configuration using a double-throw semiconductor switching device and is capable of recovering from a state where charging/discharging is inhibited with the double-throw semiconductor switching device being turned off. The charge/discharge protection circuit includes a charge/discharge control circuit which is provided with a second terminal for detecting which one of a charger and a load is connected to an external terminal. The second terminal has a first resistor and a first switch connected in series between a power source, and has a second resistor and a second switch connected in series between a ground.

Abstract: Provided are a charge and discharge control circuit capable of reducing a circuit size, and a battery device. In a charger reverse connection detection circuit (116), a comparison circuit or the like is not used, and two NMOS transistors are used, whereby circuit sizes of the reverse connection detection circuit (116) and a charge and discharge control circuit (110) are reduced. Accordingly, a consumption current is reduced, and a manufacturing cost is also reduced.

Abstract: Provided is a charge and discharge control circuit capable of further preventing poor charge of a battery, and a battery device. Cell balance periods are detected before charge of respective batteries is stopped even when an overcharge detection voltage of a certain charge and discharge control circuit becomes lower than a cell balance period detection voltage thereof due to process variations occurring in mass production of the charge and discharge control circuits. That is, the charge of the respective batteries is stopped after cell balance control. Therefore, the respective batteries can be further prevented from being poorly charged.

Abstract: Provided is a battery protection circuit and a battery device which may be manufactured at lower cost. Before all terminals of a battery protection circuit are each connected to batteries, even when a logical circuit malfunctions by an operation of a parasitic bipolar transistor formed by P-wells due to a connection order in which the batteries are connected, the logical circuit is reset by an operation of a parasitic bipolar transistor formed by the P-wells. For this reason, a charge/discharge path of the batteries is not interrupted due to the connection order. Accordingly, no limitation is placed on the connection order.

Abstract: In order to provide an overheat protection circuit having a small mounting area, the overheat protection circuit includes: a resistor bridge circuit which includes: a plurality of resistors each having a temperature coefficient; an input terminal; and an output terminal; and a comparator circuit connected to the output terminal and the input terminal of the resistor bridge circuit. Parts are each provided in the vicinity of one of the plurality of resistors each having the temperature coefficient, and the comparator circuit outputs an overheat detection signal when a temperature of one of the parts is equal to or higher than an overheat detection temperature. With this structure, a large number of parts can be protected from overheating by a minimum number of overheat protection circuits. Therefore, a circuit scale becomes smaller, and hence a cost for overheat protection becomes lower.

Abstract: Provided is a battery state monitoring circuit for manufacturing a battery device at low cost, and a battery device including the same. A charge control transistor and a discharge control transistor are structured so as to be operated based on a low-level signal which is based on a ground voltage (VSS) and a high-level signal which is based on a voltage of a voltage regulator, which is lower than a power supply voltage (VDD) based on a voltage of a battery, respectively. Accordingly, in the charge control transistor and the discharge control transistor, voltages applied to gates thereof become low, whereby a low-breakdown-voltage element can be used. This leads to a reduction in cost for the charge control transistor and the discharge control transistor, leading to a reduction in manufacturing cost for the battery device.

Abstract: Provided are a battery state monitoring circuit in which charging of a secondary battery in an over-charge detection state is prevented to improve safety, and a battery device including the battery state monitoring circuit. A circuit for consuming a leakage current is provided in the battery state monitoring circuit to prevent the secondary battery from being charged with the leakage current.

Abstract: A charge and discharge control circuit which accommodates pulsed charge and pulsed discharge and can control charge and discharge of a secondary battery with safety, and a rechargeable power supply device having the same built therein are provided. The charge and discharge control circuit includes a delay time switching circuit for shortening a delay time of overcharge detection after charge inhibition is canceled. When overcharge is detected after the charge inhibition is canceled, the charge is inhibited in a delay time which is shorter than a normal delay time of the overcharge detection.

Abstract: An overcharge detecting comparator (121) detects an overcharged state of a battery (101), and an overcurrent detecting comparator (120) detects an overcurrent state of the battery (101). In response to output signals from those comparators, a control circuit (210) performs on/off control of each of a switch (102) and a protection circuit (50). In response to an output signal from the control circuit (210), the protection circuit (50) is turned on, to thereby connect a resistor (125) to a path connecting a VSS terminal and an overcurrent detecting terminal, and is turned off, to thereby disconnect the resistor (125) from the path. As a result, even when the battery is in the overcurrent state, current consumption can be reduced.

Abstract: An object of the present invention is to provide a battery state monitoring circuit and a battery device which are capable of normally operating when a charger (301) is connected to an opposite polarity in error, and then correctly connected. In the case where the charger (301) is connected to the opposite polarity in error and then correctly connected, a logic circuit (305) does not output a power-down signal that powers down the respective circuits to the respective circuits by the aid of a power-down preventing circuit (110). As a result, the battery device normally operates without falling into the power-down state.

Abstract: Provided are a semiconductor device and a rechargeable power supply unit which are capable of accurately detecting an overcharge state of a battery even in a case where the battery is charged with a sine wave charger. In a case where a 1/2 cycle of a charging voltage of the sine wave charger is shorter than a delay time for cancellation of an overdischarge state, when it is detected that a voltage of the battery in the overdischarge state exceeds an overdischarge detection voltage and becomes equal to or higher than an overcharge detection voltage, a delay circuit sets the delay time for cancellation of the overdischarge state to 0 seconds.

Abstract: Provided is a charging and discharging protection circuit realizing low current consumption in an overcurrent detection state, easy calculation of an automatic return impedance, and high usability. A pull-down circuit for pulling down an overcurrent detection terminal to a VSS terminal is connected in series between the overcurrent detection terminal and a switching circuit. The switching circuit is connected in series between the pull-down circuit and the VSS terminal.