The Design Of Usb Otg Phy Analog Circuit Implementation

USB2.0OTG (USB On-The-Go) is the development and improvement of USB2.0. Portable equipment with USB2.0OTG interface can get rid of dependence on the PC and It can support two non-PC devices to communicate directly.It also support for switching between host and peripheral in the communication process. It also consistent with the USB2.0protocol.The maximum transfer speed can reach480Mbps.USB2.0OTG adds SRP and HNP on the basis of USB2.0protocol.In this paper Ⅰ understand the working principle of USB2.0OTG by studying USB2.0protocol, USB2.0OTG supplemental protocol and UTMI+protocol. I complete the design of OTG module and receiving circuit module.The OTG module consists of three voltage comparator, the SRP circuit and an ID detection circuit in this paper. The threshold of three voltage comparator are:4.6v,1.5v,0.5v. They are used to indicate that if the VBUS voltage is valid and to indicate that if the SRP voltage is valid. They also used to indicate that the initialization’s situation of B-device’s SRP.SRP circuit can discharge through the pull-down resistor connecting to the VBUS to ground.It also initiate HNP through the pull-up resistor. ID detection circuit can determine the role of the connected device by the type of the plug.This paper discusses the USB2.0’s composition and its basic principle. We focused on the design of high-speed data receiving circuit and the envelope signal detection circuit. We also give the relevant simulation.