Feature Story: Robust Ethernet Physical Layer Solutions for Time Critical Communications in Harsh Industrial Environments JUNE 2020 SPECIAL ISSUE Software Configurable Solutions for Industry 4.0Industry-First Truly Universal Software Controlled Analog Input AD4110-1 X Enables platform design for industrial analog input modules—saving development costs. X Designed with 2 terminals for voltage and current, thermocouples, and RTDs—reducing module size. X Internal diagnostics for increased system-level robustness—higher reliability. Learn More at analog.com/AD4110-1Contents COVER STORY Robust Ethernet Physical Layer Solutions for Time Critical Communications in Harsh Industrial Environments 4 SPOTLIGHT Analog I/O System with HART and Modbus Connectivity for PLC/DCS Applications 13 Enabling Robust Wired Condition- Based Monitoring for Industry 4.0— Part 2 13 Accelerating the Transition to Industry 4.0 with Industrial Ethernet Connectivity 13 TECHNICAL ARTICLE Feature-Rich Systems Demand Flexible and Configurable, 20 V, High Current PMICs 17 WEBCAST & VIDEO Scalable Industrial Ethernet to Accelerate Industry 4.0 26 AD5758 & ADP1031 DAC and Power Isolation Solution 27 Zero Drift, High Voltage, Low Power, Programmable Gain In Amp 27 AD74412R/13R: Quad-Channel, SW Configurable Input/Output Circuit 27 ADIS1650x Family of Precision, Miniature MEMS IMUs 27 3JUNE 2020 | www.eetimes.euRobust Ethernet Physical Layer Solutions for Time Critical Communications in Harsh Industrial Environments By Maurice O’Brien , Strategic Marketing Manager WHY ETHERNET IN INDUSTRIAL APPLICATIONS? Industrial systems are increasingly adopting Ethernet connectivity to solve manufacturers’ key Industry 4.0 and smart factory communica- tion challenges. These challenges include data integration, synchronization, edge connectivity, and system interoperability. Ethernet-connected factories enable higher manufacturing productiv- ity, and more flexible and scalable manufacturing by enabling connectivity between information technology (IT) and operating technology (OT) networks. This allows all areas of the factory to be monitored and controlled on a single, seam- less, secure, and high bandwidth network that supports time critical communications. Scaled computing and a robust communications infrastructure are the lifeblood of the connected factory. Today’s networks struggle with increas- ing traffic loads and interoperability challeng- es across myriad protocols that require com- plex, power hungry gateways to translate traffic throughout the factory. Industrial Ethernet solves these interoperability issues on a single network by delivering critical deterministic performance seamlessly to the edge of the factory. Historically, there has been an issue with a lack of available Ethernet physical layers (PHYs) designed specifi- cally for robust industrial environments. Design- ers of industrial communications equipment have had to make do and compromise for far too long with standard, consumer-grade Ethernet PHYs developed for the mass market. In the age of Industry 4.0, where the number of edge nodes is accelerating and determinism is vital to achiev- ing the connected factory, enhanced, industri- al-grade Industrial Ethernet PHYs are critical. IT VS. OT ETHERNET CONNECTIVITY Ethernet has long been used as the communica- tions choice of the IT world, given that its advan- tages include a well-supported, scalable, flexible, and high bandwidth communication solutions. It also has the interoperability benefits that come with being an IEEE standard. However, one key challenge in bridging the IT and OT networks and enabling seamless connectivity based on Ether- 4JUNE 2020 | www.eetimes.eu COVER STORY net technology is deployment in harsh industrial environments where time critical connectivity is required. INDUSTRIAL ETHERNET APPLICATION AND ETHERNET DEPLOYMENT CHALLENGES A connected motion application based on Indus- trial Ethernet connectivity for a smart factory is shown in Figure 1. Multiaxis synchronization and precision motion control are critical to high quality manufacturing and machining within smart factories. Increasing demands on produc- tion throughput and output quality are driving the need for faster response times and higher precision from servo motor drives. This improved system performance requires even tighter syn- chronization of servo motor axes used within the end equipment. Real-time 100 Mb Ethernet is widely used in motion control systems today. However, the synchronization only involves data traffic between the network master and slaves. Networks need to enable synchronization across the boundary of the network into the application from sub-1 μs right down to the PWM outputs within the servo motor control. This improves machining and production accuracy in multiaxis applications such as robotics and CNC machines based on higher data rate gigabit Industrial Eth- ernet, with IEEE 802.1 time sensitive networking (TSN). This enables all the devices to be connect- ed onto one high bandwidth converged network with real-time Industrial Ethernet protocols for edge-to-cloud connectivity. In an industrial environment, robustness and high ambient temperatures are major challenges for networking installers deploying Ethernet. Long cable runs are surrounded by high voltage tran- sients from motors and production equipment potentially corrupting data and damaging equip- ment. To successfully deploy Industrial Ethernet, as shown in Figure 1, there is a requirement for an enhanced Ethernet PHY technology that is robust and low power with low latency in a small package that can operate in a noisy and high am- bient temperature environment. This article will now discuss the challenges of deploying Ethernet PHY solutions in connected factories. Figure 1. Connected motion applications enabled by Industrial Ethernet. 5JUNE 2020 | www.eetimes.eu Cover Story WHAT IS AN INDUSTRIAL ETHERNET PHYSICAL LAYER? An Industrial Ethernet PHY is a physical layer transceiver device for sending and receiving Eth- ernet frames based on the OSI network model. In the OSI model, Ethernet covers Layer 1 (the physical layer) and part of Layer 2 (the data link layer) and is defined by the IEEE 802.3 stand- ard. The physical layer specifies the types of electrical signals, signalling speeds, media, and network topologies. It implements the Ethernet physical layer portion of the 1000BASE-T (1000 Mbps), 100BASE-TX (100 Mbps over copper), and 10BASE-T (10 Mb) standards. The data link layer specifies how communica- tions occur over the media, as well as the frame structure of messages transmitted and received. This simply means how the bits come off the wire and into a bit arrangement so that data can be extracted from the bit stream. For Ethernet, this is called media access control (MAC), which is integrated into a host processor or an Ethernet switch. See fido5100 and fido5200 as two exam- ples of ADI’s embedded, two-port Industrial Eth- ernet embedded switches for layer 2 connectivity that supports multiprotocol, real-time Industrial Ethernet device connectivity. ETHERNET PHYSICAL LAYER REQUIREMENTS FOR INDUSTRIAL APPLICATIONS 1: Power Dissipation and High Ambient Temperature Ethernet connected devices in industrial applica- tions are often are housed in sealed IP66/IP67 en- closures. IP ratings refer to how resistant an elec- trical device is to water, dirt, dust, and sand. The first digit after IP is the rating that the IEC assigned a unit for its resistance to solids. In this case, six, which means no harmful dust or dirt seeped into the unit after being in direct contact with the mat- ter for eight hours. Next, we have the water resist- ance ratings six and seven. Six means protection from water projected in powerful jets, while seven means that the device can be submerged in up to one meter of fresh water for 30 minutes. With these types of sealed enclosures, power dissipation and high ambient temperature are two major challenges for Ethernet PHY devices due to the reduced thermal conduction capability of these enclosures. To deploy Industrial Ether- net, Ethernet PHY devices with a high ambient temperature operation up to 105°C and very low power dissipation are required. Typical Industrial Ethernet networks are deployed in line and ring topologies. These network topol- ogies have reduced wiring length compared to star networks and have a redundant path in the case of a ring network. Each device connected to a line or ring network requires two Ethernet ports to pass Ethernet frames along the net- work. Ethernet PHY power dissipation becomes more critical in these use cases, as there are two PHYs per connected device. Gigabit PHY power consumption has a major impact on the over- all power dissipation and a PHY with low power consumption allows more of the available power budget for the FPGA/ processor and Ethernet switch in the device. Let’s look at the example on Figure 2, where we have a device with a power dissipation budget of 2.5 W. It includes an FPGA, DDR memory, and an Ethernet switch that requires a budget of 1.8 W. This leaves just 700 mW of available power dis- sipation budget for two PHYs. To meet the device thermal requirements, a Gb PHY with <350 mW power dissipation is required. There are limited PHY options available today that meet this power dissipation target. 6JUNE 2020 | www.eetimes.eu Cover Story 2: EMC/ESD Robustness Industrial networks may have cable runs of up to 100 m in harsh factory conditions with high volt- age transients from production equipment noise and the potential for ESD events from equip- ment installers and operators are commonplace. Robust physical layer technology for successful deployment of Industrial Ethernet are therefore essential. Industrial equipment typically needs to pass the following EMC/ESD IEC and EN standards: ▶EC 61000-4-5 surge ▶IEC 61000-4-4 electrical fast transient (EFT) ▶IEC 61000-4-2 ESD ▶IEC 61000-4-6 conducted immunity ▶EN 55032 radiated emissions ▶EN 55032 conducted emissions The cost associated with product certification to these standards is high and it is common for new product introductions to be delayed if a design iteration is required to meet any one of these standards. Significant new product development cost and risk can be reduced by using PHY devic- es that have already been tested to the IEC and EN standards. 3: Ethernet PHY Latency For applications that require real-time commu- nications, as in Figure 1, where precise control of motion is paramount, PHY latency is an important design specification because it is a critical part of the overall Industrial Ethernet network cycle time. The network cycle time is the communi- cation time required by the controller to both collect and update the data of all devices. Lower network cycle time allows for higher application performance in time-critical communications. A low latency Ethernet PHY helps achieve a mini- Figure 2. Low power Industrial Ethernet PHY devices. Figure 3. Ethernet PHY latency in Industrial Ethernet networks. 7JUNE 2020 | www.eetimes.eu Cover Story mum network cycle time and allows more devic- es to be connected to the network. As line and ring networks require two Ethernet ports to transmit data from one device to the next, Ethernet PHY latency has double the impact with two ports per device (data in port/data out port), see Figure 3. A 25% PHY latency reduction on a network of 32 devices (64 PHYs) the impact of this reduced Industrial Ethernet PHY latency is significant, both to the number of nodes that can be connected and the performance (cycle time) of that Industrial Ethernet network. 4: Ethernet PHY Data Rate Scalability It is also important to have Industrial Ethernet PHY devices that supports different data rates: 10 Mb, 100 Mb, and 1 Gb. Connections between PLCs and motion controllers require high bandwidth, gigabit (1000BASE-T) TSN Ethernet connectivi- ty. Field-level connectivity is based on Ethernet connectivity running Industrial Ethernet protocols on 100 Mb (100BASE-TX) PHYs. For end node/edge device connectivity, there is a new physical layer standard completed under IEEE 802.3cg/10BASE- T1L that will enable low power Ethernet PHY technology on single twisted-pair cables at 10 Mb bandwidth up to a distance of 1 km and can be used in intrinsically safe applications in process control. See Figure 4 for process control Ethernet connectivity and the need for scalable Ethernet PHY data rates from PLC to end node actuators and field instruments. 5: Solution Size As Ethernet technology proliferates toward the edge of industrial networks, the size of the con- nected nodes gets smaller. Ethernet connected sensors/actuators can have very compact form fac- tors and therefore require PHYs in small packages developed for industrial applications. LFCSP/QFN packages with 0.5 mm lead pitch are proven to be robust, do not require expensive PCB manufactur- ing flows, and have the advantage of an exposed paddle underneath for increased power dissipation for high ambient temperature operation. Figure 4. Process control, seamless edge-to-cloud connectivity. 8JUNE 2020 | www.eetimes.eu Cover Story 6: Product Longevity Product lifetime availability is a concern for in- dustrial equipment manufacturers because their equipment often remains active in the field for more than 15 years. This means product obso- lesce is a very costly and time-consuming prod- uct redesign activity. Industrial Ethernet PHY devices must have long product life availability, something often not supported by suppliers of consumer, mass market, Ethernet PHYs. SUMMARY OF INDUSTRIAL ETHERNET PHY REQUIREMENTS FOR ROBUST INDUSTRIAL ETHERNET APPLICATIONS Table 1. Consumer vs. Industrial Ethernet PHY Requirements Table 2. ADIN1200 and ADIN1300 Features Table 3. ADIN1300 Robust Industrial Ethernet Gb PHY EMC/ESD Robustness Testing 9JUNE 2020 | www.eetimes.eu Cover Story Next >