Ethernet PHY chip transmits 10 Mbps signals up to 1.7 km

Texas Instruments introduced a new Ethernet physical layer (PHY) capable of transmitting 10-Mbps Ethernet signals up to 1.7 km through a single pair of twisted wires. The extended cable reach of the DP83TD510E is 1.5 km more than the 200-m requirement of the Institute of Electrical and Electronics Engineers (IEEE) 802.3cg 10BASE-T1L single-pair Ethernet specification. This additional cable length helps designers extend the reach of industrial communications without increasing system weight or cabling costs.

As the complexity of factory and building automation systems continues to grow, so does the need to transmit more data to and from nodes at the network edge. The ability to directly access edge-node applications can improve control and status monitoring while also streamlining data sharing between networked systems. Current solutions for bringing connectivity to edge nodes often use a fragmented system of multiple fieldbus protocols supported by protocol conversion through network gateways. Unifying networks through protocol conversion increases complexity and cost while also limiting the ability to remotely monitor edge-node applications.

The DP83TD510E helps designers implement a single communications network, from controller to edge node, that is capable of transmitting full-duplex data over a single pair of twisted wires. By eliminating the need for additional protocols, gateways, and cables for higher-bandwidth communications, designers can simplify network management while improving system control and interoperability in long-distance applications including HVAC valve and actuator control, field transmitters, elevator main controls, and fire alarm control panels.

When upgrading to single-pair Ethernet from two-wire fieldbus technologies, such as 4- to 20-mA current loops, designers can further streamline network design and reduce installation costs by reusing existing two-wire fieldbus infrastructure for data and power transmission. The DP83TD510E is designed for use in intrinsically safe Ethernet advanced physical layer (APL) systems. Ethernet-APL is an Ethernet specification based on the IEEE 802.3.cg 10BASE-T1L standard and was developed to streamline implementation of Ethernet networking in process automation systems with intrinsic safety requirements.

Key design consideration of intrinsically safe Ethernet-APL systems – especially systems designed for use in hazardous environments with explosive potential – is the ability to reduce Ethernet PHY power levels and temperature during system failure conditions. By supporting external termination resistors, the DP83TD510E can reduce inrush current and maintain lower operating temperatures when used in long-distance process automation applications, such as field transmitters. In addition to helping designers more easily meet their intrinsic safety requirements, the DP83TD510E’s ultra-low power consumption of less than 45 mW at 1 V p2p provides additional power margin that can be reallocated to other critical circuits for increased system performance.

Pre-production versions of the DP83TD510E are available now in a 32-pin quad flat no-lead (QFN) package. Pricing starts at US$3.20 in 1,000-unit quantities. The DP83TD510E-EVM evaluation module is available for US$149. TI expects the device to be available in volume production at the beginning of 2021.