Device for automatically detecting universal serial bus main unit or peripherals

Abstract

The invention discloses a device capable of automatically detecting general-purpose serial bus hosts or peripheral equipment. In the equipment provided with a USB interface, the device is coupled to external USB equipment through a VBUS pin and judges that the external USB equipment is a USB host or USB peripheral equipment according to the change of the voltage. The device comprises a voltage detection circuit and a voltage detection element, the voltage detection circuit is respectively coupled to the voltage detection element and the VBUS pin of the USB interface. The voltage detection circuit can be a voltage-dividing circuit, and the voltage of the voltage detection circuit can change with the external input signal of the VBUS pin of the USB interface. The voltage detection element is used to detect the voltage change of the voltage detection circuit to judge that the external equipment connected with the voltage detection circuit is one USB host or USB peripheral equipment. With the invention, whether the external equipment is the USB host or the USB peripheral equipment is judged independent of the ID pin; at the same time, the power supply conflict can not be produced.

Description

technical field [0001] The invention relates to a device that can automatically detect a Universal Serial Bus (Universal Serial Bus, USB) host or peripheral device. In a device equipped with a USB interface, the device is coupled to an external USB device and judges the device connected to it. Is it a USB host or a USB peripheral. Background technique [0002] The Universal Serial Bus (USB) interface is a basic interface standard for portable devices. However, the original design of USB was to connect personal computers (PCs) as the main axis of divergence. Traditional USB was positioned between computers and peripherals from the very beginning. An interface connected to each other, USB peripheral devices cannot communicate with each other, such as a personal digital assistant (PDA) 103, a digital camera 104, a USB keyboard 105, and a USB mouse 106, etc., that is, through a hub (hub) 102a, 102b is connected with personal computer 101, such as figure 1 shown. [0003] The ...

AI Technical Summary

Problems solved by technology

[0007] Because USB OTG must rely on the ID pin to determine the role of interconnection, but when using USB OTG devices for interconnection, general users often do not understand the use of the mini-AB connector, resulting in USB OTG devices that cannot be converted into correct role (host or peripheral), causing inconvenience

[0008] Another problem is that although some application products with USB interface can already support standard (standard) and mini-AB connectors, when a USB OTG device is connected to a standard USB host, its VBUS pin There will be conflicts due to simultaneous power supply

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