New Industry Products

# Simplifying Automotive Designs with 100BASE-T1 Ethernet PHY

May 02, 2018 by Paul Shepard

Texas Instruments (TI) has introduced a new automotive Ethernet physical layer (PHY) transceiver that cuts the external component count and board space in half and consumes as little as half the power of competitive solutions.

The DP83TC811S-Q1's support for serial gigabit media independent interface (SGMII), small packaging and integrated diagnostic features enable designers to bring greater intelligence via Ethernet connectivity to space-constrained automotive body electronics, infotainment and cluster, and advanced driver assistance systems (ADAS) applications.

As the first 100BASE-T1 device to support SGMII, the DP83TC811S-Q1 Ethernet PHY improves design flexibility by enabling connections to multiple switches and interfaces. The DP83TC811S-Q1 supports the full range of media independent interfaces (MII), which enables designers to implement Ethernet connectivity with various media access controllers (MACs) and processors such as TI's Jacinto™ automotive processors.

To help the system monitor and detect cable breaks, temperature and voltage variations, and electrostatic discharge (ESD) events, the DP83TC811S-Q1 features a diagnostic toolkit, including a patent-pending ESD monitor.

Key features and benefits of the DP83TC811S-Q1 Ethernet PHY:

• Smaller solution size and lower weight: In addition to requiring fewer external components, the DP83TC811S-Q1 comes in a 6-mm-by-6-mm wettable flank package, which can reduce solution size by 50 percent. In addition, the device is compliant with the Institute of Electrical and Electronics Engineers (IEEE) 802.3bw standard and OPEN Alliance qualification, enabling the use of unshielded single twisted-pair copper cable, which reduces overall cable weight and cost.
• Lowest power consumption: Developed using one of TI's low-power process technologies, the DP83TC811S-Q1's lower power minimizes thermal dissipation and enables components to be placed closer together. The device also includes power-saving features such as standby, disable and wake-on local area network (LAN).
• Robust and intelligent design: The integrated diagnostic toolkit features cable diagnostics, temperature and voltage sensors, and an ESD monitor, enabling engineers to create designs that can withstand ESD and voltage events. The diagnostic features enable designers to continually monitor the integrity of the Ethernet link. Additionally, the DP83TC811S-Q1 provides up to 8 kV of ESD protection, helping shield the device against high-voltage faults.
• Simpler layout, flexible design and high performance: SGMII uses only four pins instead of the 12 required for reduced gigabit media independent interface (RGMII), reducing board size and number of traces and in turn simplifying the design layout. Additionally, the integration of a physical medium dependent (PMD) filter, MII series terminators, PMD termination and power-supply filtering components reduce the need for external discrete circuitry, leaving more board space for designers to add features. The DP83TC811S-Q1 has a latency as low as 140ns, allowing latency-critical systems like automotive ADAS to respond and communicate more quickly.