Exar – Bridge IC provides access to Ethernet, UART, I2C and GPIO from single Hi-Speed USB port

Exar Corporation’s XR2280x family of USB-to-Ethernet bridge ICs combines a Hi-Speed USB2.0 hub with 10/100 Ethernet and I2C controllers, Enhanced Dedicated GPIO Entity (EDGE) GPIO and up to four UARTs in a single chip.

This bridge solution provides interfaces to multiple standard communications channels from a single USB port, allowing many legacy product designs to be readily adapted for connection to the Internet of Things (IoT).

The XR22801 provides an upstream USB interface with an integrated USB2.0 PHY and device controller which supports operation at the maximum Hi-Speed USB2.0 data rate of 480Mbits/s, as well as the Full-Speed USB rate of 12Mbits/s.

Downstream, an Ethernet controller with integrated 10/100 Ethernet media access controller and PHY complies with the IEEE 802.3 specification. The XR2280x also includes an enhanced UART with a fractional baud-rate generator operating at rates from 300bits/s to 15Mbits/s, an I2C controller capable of supporting multiple masters, and an EDGE controller.

The EDGE controller supports up to 16 GPIOs. Both the EDGE pins and the I2C interface can be used for controlling and monitoring other peripherals. Up to two EDGE pins can also be configured as a PWM generator.

In addition to the XR22801, which includes a single UART, Exar also offers the XR22800 with no UART, the XR22802 with two UARTS, and the XR22804 with four UARTs.


  • Single 5.0V power supply
  • Regulated 3.3V output
  • Single 25MHz crystal
  • ±15kV ESD protection on the human body model on USB data pins
  • ±8kV ESD protection on all other pins


  • USB-to-Ethernet dongles
  • Point-of-sale terminals
  • Test instruments
  • Networking equipment
  • Factory automation
  • Process control
  • Industrial equipment