Vehicle-mounted terminal low-voltage shutdown system and method capable of preventing ignition reset

Abstract

The invention discloses a vehicle-mounted terminal low-voltage shutdown system and method capable of preventing ignition reset. The method comprises the steps that a processor monitors the output voltage of a sampled A / D sampling circuit in real time; when the monitored voltage is lower than a second preset threshold in a preset period of time, a low level control signal is output, and when the voltage output by a low-voltage shutdown control circuit is lower than a first preset threshold, a power supply conversion circuit stops outputting 3.3V power supply; when the part of the monitored voltage in the preset period of time or the whole voltage is not lower than the second preset threshold, a high level control signal is output, a first switch diode is turned on, the power supply conversion circuit is always enabled, and the power supply conversion circuit continuously outputs the 3.3V power supply. According to the system and method, a combination of software and hardware is adopted,on the one hand, when the voltage of a vehicle storage battery lowers below the threshold, a device can be powered off, and the vehicle storage battery is protected; on the other hand, the device canwork normally when a vehicle is ignited, and reset and restart caused by falling of the vehicle storage battery is prevented.

Description

technical field [0001] The invention relates to the technical field of automobile storage battery protection, in particular to a low-voltage shutdown system and method for a vehicle-mounted terminal preventing ignition reset. Background technique [0002] With the increase of automotive electronic devices, such as TBOX, OBD, driving recorder, car navigation screen, etc., these electronic devices are powered by car batteries. protect the circuit. The car multimedia navigation screen, because it provides a variety of functions such as navigation, entertainment, and radio, consumes relatively large power consumption, so a corresponding low-voltage shutdown circuit will naturally be designed. However, when the vehicle is ignited and started, due to the large drop of the car battery, the voltage supplied to the navigation screen will be lower than the low-voltage shutdown threshold, causing the navigation screen to reset. In this way, after the car is ignited, the driver needs ...

AI Technical Summary

Problems solved by technology

However, when the vehicle is ignited and started, due to the large drop of the car battery, the voltage supplied to the navigation screen will be lower than the low-voltage shutdown threshold, causing the navigation screen to reset.

In this way, the driver needs to wait for the device to restart before he can listen to music, listen to the radio, navigation and other services after the car is ignited, which brings inconvenience to the use.

Therefore, there is still a lack of a low-voltage shutdown method for the car navigation screen that can not only protect the car battery, but also prevent the car from igniting and causing the device to reset.

Images