Usb car chargers: they are usually referred to as the usb car chargers.The usb car chargers exploit the versatility of USB's versatility and they are applied to a variety of charging interfaces. Then the combination of the usb car chargers should be used in the car,and translate DC 12V and DC 24V into USB and the common 5V DC voltage of each charge. In this way, we can use the standard power supply on the car and the usb car chargers. Such as: mobile phone, MP3, navigation, game machines and all the 5V DC appliance.
First:usb car charges must be consistent with a principle, for small consumer electronics
The USB port is an economical and practical power source for the device's battery charging. To fully comply with the USB 2 specification, the load connected to the USB port must be able to communicate with the host. The load must also meet the power management requirements, including low power mode, as well as the means to facilitate the host to determine when to absorb large current from the port. Although some compatible systems are able to adapt to most USB hosts,but unexpected results may occur at times. Only a good understanding of the requirements of the USB specification and the expectation of the load,you can achieve a better balance between the compatibility of the specification and the complexity of the load. So USB car charge, from the interface to the conversion of the voltage, and the requirements of the current power to match the needs of electrical appliances. Sometimes you will encounter the USB you buy can not be charged to your electrical appliances, so that there may be a problem of matching. For example: do you use the electrical voltage is USB car charge 5V DC voltage. If the voltage is correct, it is possible that your power. USB car charging power may not match, there may be no charge, or insufficient power. At this time it is to confirm the charging current big and small is a match.