--- title: "What is Single Pair Ethernet (SPE)?" url: "https://maker.wiznet.io/scott/projects/what-is-single-pair-ethernet-spe/" markdown_url: "https://maker.wiznet.io/scott/projects/what-is-single-pair-ethernet-spe/md" type: "WCC: WIZnet Created Content" author: "scott" author_url: "https://maker.wiznet.io/scott/" original_author: "Scott" published: "2025-05-28" language: "en" tags: ["W7500"] hardware: ["WIZnet W7500"] likes: 0 views: 1452 comments: 0 source: "WIZnet Makers (https://maker.wiznet.io/)" --- # What is Single Pair Ethernet (SPE)? > What is Single Pair Ethernet (SPE)? Original author: Scott ## Components - **WIZnet W7500** x 1 ([docs](https://docs.wiznet.io/Product/Chip/MCU/W7500)) ## Article ## **– Hardware Implementation Using W7500 and Various 10BASE-T1L PHYsIndustrial communication is evolving rapidly, yet traditional fieldbus systems remain complex and segmented.Single Pair Ethernet (SPE)** addresses these issues with a streamlined technology that enables stable Ethernet communication over **just a single twisted pair cable**. This article introduces the concept of SPE and explains how to implement it using WIZnet's **W7500 MCU** and a range of **10BASE-T1L PHYs**. --- ## **What is Single Pair Ethernet (SPE)?** Conventional Ethernet uses two pairs (100BASE-TX) or four pairs (1000BASE-T) of twisted cables. In contrast, **SPE (Single Pair Ethernet)** enables Ethernet communication with **only one pair**, offering a **smaller, lighter, and long-distance-capable solution** for industrial applications. ### **✅ Key Features of SPE** - **Cable Simplification**: Ideal for space-constrained environments (robot arms, sensors, etc.) - **Low Power & Long Distance**: 10BASE-T1L supports communication up to 1km - **PoDL (Power over Data Line)**: Power and data transmitted over a single line - **Fieldbus Replacement**: Integrates well into industrial Ethernet networks ### **✅ Key SPE Standards** | **Standard** | **Speed** | **Distance** | **Description** | | --- | --- | --- | --- | | 10BASE-T1S | 10 Mbps | 15m | Multi-drop support | | 10BASE-T1L | 10 Mbps | Up to 1000m | Long distance, point-to-point topology | | 100BASE-T1 | 100 Mbps | Up to 40m | Adopted in automotive/industrial use | --- ## **Why Combine W7500 with a 10BASE-T1L PHY?** ### **✅ Overview of W7500** - ARM Cortex-M0-based MCU - **Built-in hardware TCP/IP core + Ethernet MAC** - Supports **MII interface** for external PHY connection - Includes peripherals such as UART, SPI, and Timers ### **✅ Examples of 10BASE-T1L PHY Options** Here are some widely supported PHY chips compatible with the W7500: #### **1. TI DP83TD510E** - **Features**: Compliant with IEEE 802.3cg, up to 2000m range, ultra-low power (min. 30mW) - **Interface**: MII, RMII, RGMII support - **Applications**: Industrial automation, building control #### **2. Analog Devices ADIN1100** - **Features**: Supports 10BASE-T1L, ultra-low power (min. 39mW), up to 1700m range, excellent EMI/EMC immunity - **Interface**: MII, RMII, multiple package options - **Applications**: Process control, sensor networks, industrial edge nodes #### **3. Analog Devices ADIN1110** - **Features**: Integrated MAC + PHY, SPI interface, ultra-low power, supports PoDL - **Interface**: SPI (built-in MAC-PHY) - **Applications**: Compact microcontroller-based systems, low-cost SPE modules, building automation By connecting these PHYs to the W7500, you can easily implement a **lightweight Ethernet node with direct MCU-to-PHY communication**. --- ## **Hardware Configuration: W7500 + 10BASE-T1L PHY** ### **Block Diagram** ![](https://maker.wiznet.io/upload/ckeditor5/872660302%5F1748442044%2Epng) ### **Key Hardware Connections** | **Interface** | **Description** | | --- | --- | | MII (TXD/RXD) | MAC–PHY data transfer | | MDC / MDIO | PHY register management via W7500 | | XTAL 25MHz | Required clock input for PHY operation | | Power & Ground | Typically 3.3V or 1.8V depending on PHY specs | | Protection Circuit | ESD/Noise shielding with TVS diodes, etc. | ### **MII Interface Details** The core of this configuration lies in the **MII (Media Independent Interface)** that connects W7500’s MAC to the external PHY. MII includes data lines (TXD/RXD), control lines (TX_EN, RX_DV), and clock signals. **Example pin mapping between W7500 and 10BASE-T1L PHY:** | **W7500 Pin** | **PHY Pin** | **Description** | | --- | --- | --- | | TXD[3:0] | TXD[3:0] | Transmit Data | | RXD[3:0] | RXD[3:0] | Receive Data | | TX_EN | TX_EN | Transmit Enable | | RX_DV | RX_DV | Receive Data Valid | | MDC | MDC | Management Data Clock | | MDIO | MDIO | Management Data I/O | | CLK | 25MHz Input | Clock Synchronization | Additional requirements include appropriate **power supply design**, **crystal oscillator**, **reset circuitry**, and **protection against ESD and electrical noise**. ### **Notes** - Most 10BASE-T1L PHYs use **SPE-specific connectors** (e.g., IEC 63171-1/6), not standard RJ-45. - The MDI side often requires **transformers or common-mode chokes** for signal integrity. --- ## **Conclusion: SPE is the Future of Industrial Networking** Combining W7500 with a selection of 10BASE-T1L PHYs offers a **practical, cost-efficient approach to implementing SPE-based edge devices**. This setup enables high-speed, long-range Ethernet over a single pair—without relying on expensive SoCs. > 🌐 *“Bring Ethernet to the edge with the next-generation industrial standard—start your SPE project today.”* --- ## **Reference Links** - [WIZnet W7500 Product Page](https://www.wiznet.io/product-item/w7500p/) - [TI DP83TD510E Product Page](https://www.ti.com/product/DP83TD510E) - [Analog Devices ADIN1100 Product Page](https://www.analog.com/en/products/adin1100.html) - [Analog Devices ADIN1110 Product Page](https://www.analog.com/en/products/adin1110.html) - [IEEE 802.3cg SPE Standard Overview](https://standards.ieee.org/ieee/802.3cg/7022/) --- Source: https://maker.wiznet.io/scott/projects/what-is-single-pair-ethernet-spe/