Method and circuit for detecting battery

Abstract

The embodiment of the invention relates to the field of a circuit, in particular to a method and a circuit for battery detection, which is used for accurately detecting a battery state. The method disclosed by the embodiment of the invention comprises the following steps of discharging a battery circuit, detecting a first voltage of the battery circuit, and judging that the battery exists if the first voltage is greater than a first threshold value; otherwise judging the battery is in a first pending state, controlling a charging circuit to charge the battery circuit, judging the battery is in a second pending state after the charging circuit is controlled to charge the battery circuit, controlling a discharging circuit to discharge the battery circuit, and detecting a second voltage of the battery circuit; and judging that the battery does not exist if the second voltage is smaller than a second threshold value, otherwise judging that the battery exists. The non-existence state of the battery and the state that the battery exists and is in short-circuit protection state can be distinguished by the processes of discharging, charging and discharging again, and thus, the problem that the two states are confused only by discharging or charging is prevented.

Description

technical field [0001] The invention relates to the field of circuits, in particular to a method and circuit for detecting batteries. Background technique [0002] In daily life, when a device powered by a lithium battery, such as a mobile phone or a tablet computer, is plugged into an adapter, it is necessary to determine whether the device is connected to a battery. If the device is connected with a battery, the charging circuit inside the device is turned on, the battery is charged through the adapter, and the charging circuit is turned off when the battery is fully charged. If the device is not connected to the battery or is in a short-circuit state, but the charging circuit inside the device is still turned on, the output current generated by the charging circuit will cause the voltage at the output end of the charging circuit to rise rapidly, thereby forming heat energy and voltage at the output end of the charging circuit. , which may cause damage to the entire circu...

AI Technical Summary

Problems solved by technology

If the device is not connected to the battery or is in a short-circuit state, but the charging circuit inside the device is still turned on, the output current generated by the charging circuit will cause the voltage at the output end of the charging circuit to rise rapidly, thereby forming heat energy and voltage at the output end of the charging circuit. , which may cause damage to the entire circuit, therefore, if the device is not connected to the battery or the battery is short-circuited, the charging circuit cannot be turned on for a long time

Images