Over-charge voltage protection detection circuit and system

Abstract

The invention discloses an over-charge voltage protection detection circuit and system. The over-charge voltage protection detection circuit comprises a detection module, a first switch module, a second switch module, a voltage dividing module, a comparison module and a reference generating module; the detection module controls the first switch module to be turned on and the second switch module to be turned off; the voltage dividing module is used for sampling an input voltage of a power input end and outputting a sampled voltage to the comparison module; the reference generating module outputs a reference voltage to the comparison module; when the sampled voltage is higher than the reference voltage, the comparison module outputs a first level signal to the detection module, and the detection module controls the input voltage to be reduced to a preset voltage; and when the sampled voltage is lower than the reference voltage, the comparison module outputs a second level signal to thedetection module, and the detection module controls the input voltage to be increased to the preset voltage. By stabilizing the input voltage at an over-charge voltage protection threshold point, accurate measurement on the over-charge voltage protection threshold point is achieved.

Description

technical field [0001] The invention relates to the technical field of circuit protection, in particular to an overcharge voltage protection detection circuit and system. Background technique [0002] The current battery protection chip on the market integrates the discharge NMOS tube, charging NMOS tube and battery protection control circuit on the same chip around the traditional single-cell battery protection chip. like figure 1 As shown, under normal circumstances, the charge and discharge control signal output by the battery protection control circuit 11 inside the battery protection chip 10 is a high level CDO, and the charge and discharge isolation NMOS transistor M0 is turned on. When the battery voltage is lower than the overvoltage discharge protection threshold set by the battery protection control circuit 11 during battery discharge, or the discharge current is higher than the overcurrent discharge protection threshold set by the battery protection control circu...

AI Technical Summary

Problems solved by technology

Although this method reduces the test time and test cost accordingly, it is tested by scanning card points, that is, it is gradually increased one by one, and the voltage increased each time is a range, not an accurate value , the accuracy of the measurement cannot be guaranteed, and there will be an interval between each increase in the voltage, which will affect the test efficiency

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