Usb charging module for vehicle and charging method thereof

Abstract

A USB charging module for a vehicle includes a power supply interface, a voltage conversion circuit, a plurality of USB interface power supply branches, a communication interface and a controller. The power interface is used to electrically connect to the output terminal of the vehicle battery. The input terminal of the voltage conversion circuit is connected with the power interface. Each USB interface power supply branch includes a first switch circuit, a current detection circuit and a USB interface connected in sequence, and the first switch circuit is connected to the output end of the voltage conversion circuit. The communication interface is used to communicate with the electronic control unit of the vehicle. The communication end of the controller is connected to the communication interface, the input end is respectively connected to the output ends of the current detection circuits of the plurality of USB interface power supply circuits, and the output ends are respectively connected to the control input ends of the first switch circuits of the plurality of USB interface power supply branches . The invention also discloses a charging method of the USB charging module for the vehicle. The invention can automatically and intelligently manage the USB charging equipment when the car is in the state of parking and turning off the engine.

Description

technical field [0001] The invention relates to the field of automobiles, in particular to a USB charging module for a vehicle. Background technique [0002] Cars are a common means of travel in people's daily lives. As consumers use mobile devices and in-vehicle devices more and more frequently, the demand for charging or data interaction of such devices in cars is also increasing. In the past, the combination of USB multimedia interface and cigarette lighter interface appeared on most models. The USB interface can only provide a current below 500mA, so it is only suitable for connecting multimedia devices (such as U disk) for audio and video playback. Users need to purchase vehicle-mounted equipment suitable for the cigarette lighter interface, or purchase an additional USB car charger to insert into the cigarette lighter interface to supply power to the device with the USB interface. In order to improve the convenience of users, some manufacturers have equipped the car ...

AI Technical Summary

Problems solved by technology

Some of these models do not have any power management and protection measures at all, so there is still the risk that the battery cannot be started due to excessive discharge or power loss; in addition, there are a small number of models that can detect the battery voltage when the engine is turned off. Cut off the power supply of the car USB module when the voltage is low

But it still has many problems: there is hysteresis, when the low voltage is detected, the battery is already in a state of insufficient power, and there are no management measures before that; after the engine is turned off, the high-power electrical appliances connected to the USB interface cannot be timely Shut down, resulting in waste of power; the voltage threshold needs to be set in advance, however, when the battery is cycled for a certain period of time / times, the battery will age. Under the same preset voltage threshold, the battery can no longer start the engine normally or can only meet one normal start, which increases the risk of engine start failure, that is, this management method is not applicable to the entire battery The low temperature environment will also cause the available power in the battery under the preset voltage threshold to be lower than the normal use environment; in addition, the detection method is to cut off all USB power supplies after the battery is found to be low, and the use of safety equipment such as driving recorders affected

In summary, there is still a lot of room for improvement in the prior art automotive USB modules

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