A simple vehicle battery detection and protection circuit

Abstract

The invention discloses a simple vehicle battery detection and protection circuit, comprising a battery input terminal, a protection circuit, a high-voltage LDO circuit, a first comparator, a second comparator and a switch circuit, the battery input terminal is connected to the positive pole of the vehicle battery, and the output terminal The protection circuit is connected to the input end of the high-voltage LDO circuit, and the high-voltage LDO circuit outputs 5V voltage to the first and second comparators; the first comparator sets the threshold voltage, identifies the voltage of the vehicle battery and outputs the corresponding high / low level to The negative input terminal of the second comparator, the output terminal of the second comparator is connected to the switch circuit; if the voltage value of the vehicle battery is lower than the voltage preset value, the second comparator outputs a high level, and the enabling terminal of the switch circuit is pulled by the transistor low, power is off. On the basis of not adding single-chip microcomputer chips, the invention realizes the monitoring and protection of the on-vehicle battery through hardware, can realize effective protection of the on-vehicle batteries of different voltages, has low power consumption, and effectively prevents battery feeding problems.

Description

technical field [0001] The invention relates to the vehicle field, in particular to a simple vehicle battery detection and protection circuit. Background technique [0002] With the rapid growth of annual production, sales and car ownership in China, the release of demand for new purchases and the improvement of residents' consumption ability, it is expected that the trend of upgrading automobile consumption will continue in the future, and consumers' demand for vehicle safety control and interactive experience will further expand. It is estimated that in the next 10 years, the cost of electronic equipment on the car will account for more than 30% of the entire car cost. There are more and more types of vehicle equipment, such as driving recorder, GPS navigation, vehicle radar, WIFI, Bluetooth, 4G, etc. Vehicle electronic equipment generally does not have independent battery power supply, but directly uses the car battery as the power supply. [0003] When the car engine is...

AI Technical Summary

Problems solved by technology

At this time, if the power supply current of the on-board equipment is still relatively large or the engine stops for a long time, the car battery continues to discharge, and the discharge will not stop, which will cause power feeding, resulting in ACC ignition failure

[0004] At present, the common smart vehicle electronic equipment only adopts ACC OFF sleep low power consumption design for the car battery, and does not do low voltage protection or foolproof to prevent the battery feed caused by the abnormal sleep of the vehicle electronic equipment.

Devices with low-voltage protection are either expensive or incompatible with different battery voltage (12V&24V) models

[0005] At present, the existing technology needs to add an additional single-chip microcomputer for control, which increases the use space of the product PCB and hardware costs, and increases the workload of burning software; and for different models, different customers have different low-voltage protection requirements. The single-chip microcomputer needs to add different programming programs; and the current consumption of the single-chip microcomputer is high, and there is a risk of consuming battery power

In addition, most of the current designs can only be used for one voltage vehicle, and cannot be compatible with 12V & 24V models at the same time

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