USB to Ethernet & UART bridge simplifies application, offers greater integration

August 06, 2014 // By Graham Prophet
The XR2280x device provides 10/100 Ethernet, UART, I2C and EDGE GPIO from a single Hi-speed USB port.

Exar's XR2280x family of USB to Ethernet bridge ICs combine a Hi-Speed USB 2.0 hub with controllers for 10/100 Ethernet, I2C, EDGE GPIO, and up to four UARTs in a single chip. This bridge solution, providing multiple communication standards from a single USB port, will allow many legacy product designs to be readily adapted for connection to the Internet of Things (IoT). The devices also serve the markets for industrial equipment, factory automation, networking, test and POS terminals, and many other embedded applications.

The XR22801 provides an upstream USB interface with an integrated USB 2.0 PHY and device controller that is compliant with USB 2.0 Hi-Speed (480 Mbps) and Full-Speed (12 Mbps) transfer rates. Downstream there is an Ethernet controller with integrated 10/100 Ethernet MAC and PHY compliant to IEEE 802.3, an enhanced UART with a fractional baud rate generator (supporting 300 bps to 15 Mbps), a multi-master capable I2C controller, and an Enhanced Dedicated GPIO Entity (EDGE) controller. The EDGE controller supports up to 16 GPIOs and both the EDGE pins or I2C interface can be used for controlling and monitoring other peripherals. One or two EDGE pins can also be configured as a PWM generator. In addition to the XR22801, which integrates a single UART, Exar also offers the XR22800 with no UART, the XR22802 with two UARTS, and the XR22804 with four UARTs.

The XR2280x family is available in 32 or 56 pin QFN packages and is priced from $2.85 to $4.15 (1000).