Detection protection and control system with charging function

Abstract

The invention provides a detection protection and control system with a charging function. The system comprises a single-chip microcomputer MCU, an alternating current adapter, a battery charging circuit, an input level conversion circuit, an adapter input voltage detection and wake-up circuit and a direct current load control circuit, the alternating current adapter is connected with the battery charging circuit, the battery charging circuit is connected with the input level conversion circuit, the input level conversion circuit is connected with the single-chip microcomputer MCU, the DC load control circuit is connected with the battery charging circuit and the single-chip microcomputer MCU, and the adapter input voltage detection and wake-up circuit is connected with the AC adapter and the single-chip microcomputer MCU. An external voltage reference circuit is added, and negative voltage of a detection I / O port of a charging circuit is converted into positive voltage to be output, so that the MCU can perform normal detection, the ADC detection range is expanded, the detection result is more accurate, and the algorithm is simple.

Description

technical field [0001] The invention relates to the field of circuit technology, in particular to a detection, protection and control system with a charging function. Background technique [0002] At present, the electric and electric heating appliances with charging function need to detect the charging current and discharging current in the process of use, so as to play the role of control and protection. There are three schemes for implementing the charging function detection and control system: [0003] Option 1: If Figure three , BGND, MGND, VSS, and GND are common ground. When charging, the current flows out of the adapter, and then passes through the battery charging circuit, battery, BGND, charging detection resistor, and GND in sequence. The specific path is shown in the figure. The magnitude of the charging detection current is fed back to the MCU by the charging detection resistor to realize the charging current detection; when discharging, the current flows out...

AI Technical Summary

Problems solved by technology

The magnitude of the discharge detection current is fed back to the MCU by the discharge detection resistor to realize the discharge current detection. In the battery charging circuit, the charge detection resistor will feed back a negative voltage to the MCU. In theory, the I / O port of the MCU is not allowed to have a large negative voltage. Therefore, it is necessary to finely calculate and adjust the charging detection resistor so that the negative pressure fed back to the MCU IO port cannot exceed the maximum value that the MCU I / O port can withstand (this situation will greatly reduce the range of the ADC, and the algorithm implementation is abnormal. Difficult, the detection accuracy is greatly reduced), to ensure that the MCU is normal

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