Lithium-battery protection chip circuit based on PTC (Positive Temperature Coefficient) elements

The utility model discloses a lithium-battery protection chip circuit based on PTC (Positive Temperature Coefficient) elements. The circuit comprises an IC chip U1, capacitor-resistor elements, a MOSFET switch device and a PTC thermistor. The IC chip U1 detects the voltage of the battery and the circuit current by the capacitor-resistor elements, and controls the connection and disconnection of a charge circuit and a discharge circuit through the MOSFET switch device. The PTC thermistor is connected in series between the capacitor-resistor elements and the battery. By adopting the above circuit structure, the conventional lithium-battery protection chip circuit is additionally provided with the PTC thermistor, so that the temperature detection function is achieved, and when it is detected that the internal temperature of the lithium-battery protection chip circuit is too high, the lithium-battery protection chip circuit is broken, providing high practicability. The circuit provided by the utility model is sim