Charge and discharge control circuit, charge and discharge control unit, and battery device
View Patent ↗Provided is a highly safe battery device in which the accuracy of an overcurrent detection current value is high. A charge and discharge control circuit includes an overcurrent detecting terminal, an overcurrent detecting circuit for detecting overcurrent of a secondary battery, the overcurrent detecting circuit being connected to the overcurrent detecting terminal, and a constant current circuit for causing a current to flow to the overcurrent detecting terminal.
1. A charge and discharge control circuit for detecting a voltage and abnormality of a secondary battery, the charge and discharge control circuit comprising:
an overcurrent detecting terminal;
an overcurrent detecting circuit for detecting overcurrent of the secondary battery, the overcurrent detecting circuit being connected to the overcurrent detecting terminal;
a resistor connected to the overcurrent detecting terminal;
a constant current circuit for causing a current to flow to the overcurrent detecting terminal and the resistor;
wherein the overcurrent detecting circuit compares a reference voltage with a voltage of the overcurrent detecting terminal including a voltage generated by the current flowing through the resistor; and
wherein the resistance value of the resistor is adjusted to set an overcurrent detection current value at a predetermined setting value and a threshold voltage for the overcurrent detecting circuit to output a detection signal is a voltage having the value of the voltage generated by the current flowing through the resistor subtracted from the reference voltage.
2. A charge and discharge control circuit according to claim 1 , wherein the overcurrent detecting circuit comprises:
a reference voltage circuit; and
a comparator circuit for comparing a voltage of the overcurrent detecting terminal with a voltage of the reference voltage circuit.