New Industry Products

PCIe 3.1 Ethernet Bridge Integrates Power, Clocks, and PHY Interface

February 13, 2019 by Scott McMahan

Microchip Technology has launched an Ethernet bridge for embedded and automotive platform designers. The company designed the bridge for Peripheral Component Interconnect Express® (PCIe®) 3.1 Low-Power Sub-State (LPSS) L1.1 and L1.2 for power savings. The LAN7430 Ethernet bridge integrates power, clocks, and an Ethernet physical (PHY) interface, while the LAN7431 provides Reduced Gigabit Media-Independent Interface (RGMII) for alternative PHYs and switches.

The LPSS L1.1 (snooze) and L1.2 (off) functions enable designers to reduce power consumption and improve battery life by snoozing or turning off the high-speed circuits in the PHY when not in use.

When connected to an application System on Chip (SoC) or processor as host, the LAN7430/1 allows the host device to deliver audio, data, or video data through the 10/100/1000 Ethernet network. Connection to the host is achieved via the PCIe 3.1 specification, providing up to 2.5 Gigatransfers per second (GT/s) in each direction simultaneously.

The LAN7431's RGMII interface allows the freedom to design with alternative link layers such as IEEE 802.3bw-2015 (100Base-T1) for 100Mbps and 802.3bp-2016 (1000Base-T1) operation over a single twisted pair cable. It also supports real-time Ethernet, IEEE 1588-2008 (PTP), and IEEE 802.1AS (gPTP) Precision Time Protocols. The LAN7431 offers an automotive variant that exceeds AEC-Q100 Grade 2 (-40°C to +105°C) qualification.

With the new offering, Microchip provides worldwide technical support, design review services of final designs, and fully released drivers for Linux® or Windows® operating systems.

"In a market where many vendors are either announcing end-of-life on a current product or sending messages that indicate potential longevity issues, Microchip is stepping in to meet customer demand," said Charles Forni, director of Microchip's USB and networking business unit. "The new devices also meet customer requirements of PCIe 3.1, low-power sub-states for power saving that is important in automotive, but especially so for hand-held or single-board computers in industrial applications."

A true single-chip solution, the LAN7430/1 family provides a single 3.3V supply operation, removing the need for complex and costly power management support. Both devices integrate a JTAG (1149.1) Test Access Port (TAP) for enhanced test coverage. Microchip also offers LINK MD® diagnostics utilizing Time Domain Reflectometry (TDR) to analyze the cabling harness, identifying and locating common cabling problems such as open circuits, short circuits and impedance mismatches.

Development Tools

The LAN7430 and LAN7431 are backed by Microchip's free LANCheck® online design review service that reviews customer designs, ensuring that best design practices are used. Microchip's MPLAB® Connect software tool is provided for programming One-Time-Programmable (OTP) memory, or the optional EEPROM memory, for easy device configuration. Microsoft Windows Hardware Quality Labs (WHQL) certified drivers are available along with Linux mainline kernel drivers for both networking and PTP and gPTP synchronization. Evaluation boards (EVB-LAN7430 and EVB-LAN7431) are also available.

Pricing and Availability

The LAN7430 is available for $3.95 each in 1,000-unit quantities in a 48-lead QFN package. The LAN7431 is available for $3.59 each in 1,000-unit quantities in a 72-lead QFN package.