By Henry Muyshondt, Senior Manager, Microchip Technology, Inc.
Microchip has introduced new industrial-grade Single Pair Ethernet devices that implement the 10BASE-T1S and 100BASE-T1 physical layer. These products bring Ethernet all the way to the edge of industrial networks.
Single Pair Ethernet, or SPE, defines the transceiver part of an Ethernet system. All the higher software layers remain unchanged, regardless of the speed grade. SPE is also referred to as T1, which means one balanced pair of wires. Some applications use a twisted pair of wires, but others use just two wires running alongside each other. The IEEE standard defines a channel in terms of its electrical characteristics and not the specific physical wires.
Multiple bandwidths are defined for SPE. The first part of the name specifies the Mbit/s: 10BASE means 10 Mbit/s. There are standards for 10BASE-T1S (S for Short reach), 10BASE-T1L (L for Long reach), 100BASE-T1, 1000BASE-T1 and even higher data rates are defined for 2.5, 5 and 10 Gbit/s. SPE reduces system cost by reducing weight and wiring complexity.
The megatrend in networking is to move from distributed systems defined primarily by the hardware involved, to more centralized, software defined systems. The trend is to connect everything with Ethernet:
- Domain-specific hardware architectures give way to zones connected to each other and to a centralized compute platform.
- Multiple application-specific buses are replaced by an IP-based and ubiquitous Ethernet network.
- Gateways or controllers required to translate between different hardware approaches and that require complex wiring are eliminated. Low-cost, single pair cabling then brings Ethernet all the way to the edge of the network.
All this results in a more powerful, more flexible network to meet industrial challenges.
Ethernet enables connected Cloud-to-Edge infrastructures. Traditional IT networks at the top enable communications at the highest levels. Operational Technology (OT) networks are used within buildings to control processes and assembly lines. As you get closer to the edge of the enterprise network, you find sensors, actuators, and other low-level devices.
Ethernet allows a common way to connect and communicate with all these elements to make their data available to higher levels of the organization so Big Data can use it to better run the enterprise. It also makes it easier to configure and control systems. Established Ethernet mechanisms can secure all these elements. Authentication, encryption, and secure updates are an increasingly important aspect of today’s networking requirements.
Microchip has been a leader in the development of Single Pair Ethernet. It helped write the standards at the IEEE and has in parallel developed a comprehensive portfolio of SPE solutions that are flexible and scalable. Whether running at 10Mbits/s, 100Mbits/s or 1000 Mbits/s, Microchip has a PHY, MAC-PHY or Ethernet switch that can drive a single pair of wires to transmit the data.
10BASE-T1S technology is one of the newest types of Ethernet interconnection defined by the IEEE.
The IEEE 802.3cg standard was published in 2019. Microchip was one of the key participants that created the standard within the IEEE. This standard was developed to expand Ethernet to the edge of Operational Technology or OT networks. Existing systems had bandwidths of hundreds of kilobits per second, so going to megabits per second provides for future growth.
The technology uses half-duplex communication and provides for a flexible topology, from point-to-point to multidrop configurations. Multidrop means that multiple devices connect to a bus line made up of a single pair of wires.
10BASE-T1S is defined to use a single balanced pair of conductors. This can be a single twisted pair of wires, other configurations for wire pairs, or even parallel traces on a printed circuit board or server backplane.
The new 10BASE-T1S standard define a physical layer that creates new business opportunities for companies that embrace pervasive all-Ethernet systems. Data anywhere in the system can be used in innovative ways that enable new applications.
Cost can be reduced since 10BASE-T1S uses simple components, software, and wiring. A new 10BASE-T1S MAC-PHY Ethernet controller now in the marketplace allow the simplest of microcontrollers to become part of the Ethernet world. 10BASE-T1S eliminates the need for gateways previously required to translate data from different hardware systems. The multidrop feature reduces the number of ports in switches as devices connect to a single bus line.
Using well-established security mechanisms and the unified interfaces of the Ethernet world reduces risks when creating applications at the edge of industrial networks. Security mechanisms are well understood by a large body of designers and implementers. Any issues can be quickly discovered given how many people work with the technology, and they can also be quickly resolved. Design, software development, testing and maintenance resources at all levels of OT and IT networks can concentrate on the same basic communication mechanisms.
Microchip offers a complete range of SPE PHYs, from 10Mbits/s to 1000Mbits/s, all offering Industrial grade temperature support. Further enhanced support for industrial applications includes safety, security and extended cable reach. Complete SPE networked systems solutions can be realized with a broad portfolio of SPE switch devices. Microchip offers intelligent switches that support Time Sensitive Networking (TSN) and integrated SPE PHY technology. Our latest release is an industry first true single-chip SPE switch with TSN support, integrating switch fabric, CPU, RAM and uniquely FLASH code memory. Designers can now implement ‘out of the box’ Single-Pair switching solutions, with little or no expertise on T1 PHY technology or AVB and TSN specifications.