USB Electrical Characteristics

The USB sub-system supports one DRD (dual-role device)/OTG (on-the-go) port, which uses separate host controller (xHCI) and device controller (xDCI) IPs. As a host, it can connect to any standard USB 1.1, 2.0, or 3.0 device. As a device, it can connect to any host and can expose various SoC capabilities based on what drivers are available. The USB interface has the following features:

  • USB 3.0 – one host only, and one OTG (host or device)
  • Max USB 3.0 Speed – 5 Gb/s
  • USB 2.0 – two host only, and one OTG
  • Max USB 2.0 Speed – 480 Mb/s

Refer to Universal Serial Bus Interface Specifications for additional specifications of the USB controller.

USB Controllers

The USB subsystem incorporates the xHCI Host Controller, and USB 3.0 Controller configured as a USB Device only (xDCI).

A typical platform is expected to use a micro-AB connector on the OTG port.

USB Connect or Disconnect Scheme - Connector Dependent

Receptacle Plug Way of Detection Action
Micro-AB on OTG only Micro-A ID pin pulled to GND (PMIC) OTG start as Host (selected by software)
Micro-AB on OTG only Micro-B VBUS sensing (PMIC)  OTG start as device (selected by software)


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