Abstract: A voltage detection circuit, a charge control circuit, a charge and discharge control circuit, and a semiconductor device are provided. The voltage detection circuit includes: an input port; a plurality of transistors connected in series and including at least an input transistor including a gate connected to the input port, a source connected to a first power supply terminal, and a drain, and a first transistor including a drain connected to a second power supply terminal, a gate, and a source connected to the gate of the first transistor; and an output port configured to be one of connection points of the plurality of transistors.

Abstract: A charge/discharge control circuit includes: an output terminal from which a cell-balance control signal is sent to each of the first and the second cell balance circuits; the first and the second voltage detection circuits; a control circuit configured to send the first and the second control signals in accordance with a detection signal received from at least one of the first and the second voltage detection circuits; and an output circuit configured to select one of a voltage of a power supply terminal, a voltage of an input terminal connected to each of a negative electrode of a first battery and a positive electrode of a second battery, and a voltage of a ground terminal in accordance with the first and second control signals, and send the selected voltage to the output terminal.

Abstract: A charge-discharge control circuit includes a first cell balancing circuit having a first switch; a second cell balancing circuit having a second switch; a first cell balance detection circuit having a third switch; a second cell balance detection circuit having a fourth switch; and a control circuit which outputs a control signal to turn on the first switch in a prescribed cycle according to the voltage of a first battery which is higher than or equal to a cell balance detection voltage, or outputs a control signal to turn on the second switch in the prescribed cycle according to the voltage of a second battery which is higher than or equal to the cell balance detection voltage, and outputs a control signal to turn off the third switch and the fourth switch in the prescribed cycle during output of the control signal.

Abstract: A charge/discharge control circuit includes: an output terminal from which a cell-balance control signal is sent to each of the first and the second cell balance circuits; the first and the second voltage detection circuits; a control circuit configured to send the first and the second control signals in accordance with a detection signal received from at least one of the first and the second voltage detection circuits; and an output circuit configured to select one of a voltage of a power supply terminal, a voltage of an input terminal connected to each of a negative electrode of a first battery and a positive electrode of a second battery, and a voltage of a ground terminal in accordance with the first and second control signals, and send the selected voltage to the output terminal.

Abstract: A charge-discharge control circuit includes a first cell balancing circuit having a first switch; a second cell balancing circuit having a second switch; a first cell balance detection circuit having a third switch; a second cell balance detection circuit having a fourth switch; and a control circuit which outputs a control signal to turn on the first switch in a prescribed cycle according to the voltage of a first battery which is higher than or equal to a cell balance detection voltage, or outputs a control signal to turn on the second switch in the prescribed cycle according to the voltage of a second battery which is higher than or equal to the cell balance detection voltage, and outputs a control signal to turn off the third switch and the fourth switch in the prescribed cycle during output of the control signal.

Abstract: Provided are a charge and discharge control circuit having a small circuit area and a compact battery device. A constant current circuit and an external resistor are connected to a voltage monitoring terminal so that a terminal voltage is pulled up or pulled down based on an external input. Moreover, output logic of a comparator and overcharge detection and overdischarge detection are switched based on the external input.

Abstract: Provided are a charge and discharge control circuit having a small circuit area and a compact battery device. A constant current circuit and an external resistor are connected to a voltage monitoring terminal so that a terminal voltage is pulled up or pulled down based on an external input. Moreover, output logic of a comparator and overcharge detection and overdischarge detection are switched based on the external input.

Abstract: There are provided an overcurrent protection circuit which has a smaller circuit area, a charging and discharging control circuit, and a compact battery device. The charging and discharging control circuit includes an overcurrent detection circuit which monitors the voltage of an overcurrent detection resistor connected to an overcurrent detection terminal and which detects the flow of an overcurrent into a secondary battery, an overcurrent release circuit which monitors the voltage at a terminal to which a load is connected through a voltage step-down circuit connected to an overcurrent release terminal and which detects the removal of a load, and a clamping circuit connected to the overcurrent release terminal are provided. The voltage at the overcurrent release terminal is clamped by the voltage step-down circuit and the clamping circuit.