Reference platform for robust 10BASE-T1S Ethernet design

A new system-level reference design platform has been introduced to expedite the adoption of Single-Pair Ethernet (SPE) in industrial and building automation applications. The REF_SPE_T1S platform, a result of collaboration between Arrow, Microchip, Bourns, and Amphenol, offers engineers a practical evaluation environment as they transition from traditional fieldbus technologies to Ethernet at the edge.

One of the primary challenges in deploying SPE is ensuring signal integrity and electromagnetic compatibility (EMC) in environments with high electrical noise. The platform emphasizes the increasing significance of magnetics design in achieving reliable Ethernet communication beyond the PHY layer.

Magnetics design plays a crucial role in driving SPE performance. The REF_SPE_T1S platform is centered around Microchip’s LAN8670 10BASE-T1S PHY and an IEC 63171-6 compliant SPE connector from Amphenol. At its heart lies an integrated magnetics solution from Bourns, which combines an isolation transformer and common-mode choke (CMC) in a single component.

The design showcases how the magnetic interface between the PHY and cable significantly impacts overall SPE performance. The integrated transformer-based isolation enhances common-mode noise rejection and galvanic isolation, particularly at low frequencies, an area where capacitor-only isolation methods may fall short.

This improved noise suppression aids in maintaining signal integrity and stable connections in challenging industrial settings, where conducted and radiated interference can compromise communication reliability. Additionally, the approach enhances emissions margins, facilitating compliance with EMC standards.

With the shift away from legacy communication standards like CAN and RS-485 in industrial systems, SPE is emerging as a vital facilitator for Ethernet connectivity down to the sensor and actuator level. The REF_SPE_T1S platform is positioned as a supportive tool for this transition, offering engineers tangible insights into network robustness.

The USB-powered evaluation board enables engineers to compare transformer-based isolation with capacitor-based designs in real-time. It supports both point-to-point and multidrop 10BASE-T1S configurations, allowing for the validation of network stability and channel performance before finalizing product designs.

Target applications for this platform include industrial automation, HVAC and building control systems, as well as embedded edge devices that necessitate reliable, low-speed Ethernet connectivity. By providing a reference schematic and a live testing environment, the platform aims to mitigate design risks and expedite the time-to-market for SPE-enabled products.

Overall, the REF_SPE_T1S underscores the critical importance of carefully optimizing the physical layer, including magnetics and isolation strategies, as Ethernet continues to penetrate increasingly demanding edge environments. Developers can apply for samples of the platform on the Arrow webpage.