This reference design adds four 100Base-T1 and 1000Base-T1 automotive Ethernet ports to Jacinto 7 EVMs using TI’s robust PHYs, BAW-based clocking, and efficient power management—ideal for ADAS, infotainment, and software-defined vehicles.
This reference design TIDA-020071 by Texas Instruments (TI) enables seamless automotive Ethernet interfacing with Jacinto 7 processor evaluation modules (EVMs) through the RGMII Ethernet Expansion Connector. It adds four automotive Ethernet ports using Texas Instruments’ (TI) automotive-qualified physical layer transceivers (PHYs): the DP83TC818S-Q1 supporting 100Base-T1 and the DP83TG721S-Q1 supporting 1000Base-T1 single-pair Ethernet (SPE). The design also demonstrates the ability to couple 12V power onto the data line using an automotive-grade filter network, making it suitable for battery-connected automotive systems.
This setup supports both 100 Mbps and 1 Gbps automotive Ethernet through RGMII, enabling high-speed connectivity to Jacinto™ 7 processors used in a wide range of in-vehicle systems. The board allows a common clock to be distributed to all four PHYs via a TI Bulk Acoustic Wave (BAW) oscillator and a clock buffer. There is also an option to populate the BAW oscillator directly on the board. The inclusion of a board ID EEPROM provides system-level identification for configuration and diagnostics.
The DP83TC818S-Q1 PHY is compliant with IEEE 802.3bw and Open Alliance standards, supporting physical layer functions and flexible xMII interfaces over an unshielded single twisted-pair cable. It features the OA TC-10 low-power sleep mode and wake forwarding, making it ideal for power-sensitive automotive environments. The design also incorporates TI’s TPS7B82-Q1 and TPS74701-Q1 low-dropout (LDO) linear regulators to efficiently manage power. The TPS7B82-Q1 is especially suited for always-on systems, operating from 3V to 40V with load dump protection up to 45V, and features an ultra-low quiescent current of 2.7µA at light load. It ensures reliable power during cold crank and start-stop conditions, ideal for automotive MCUs and transceivers.
Meanwhile, the TPS74701-Q1 offers a user-programmable soft-start, power-good output, and enable control for robust sequencing of multiple power rails. This supports stable start-up and operation for a wide range of processors and ASICs. Complementing these components, TI’s BAW technology enables precise, low-jitter clock generation with micro-resonators integrated directly into the chip package—offering enhanced timing performance for high-speed data communication.
Designed for applications such as advanced driver assistance systems (ADAS), infotainment and cluster modules, body electronics, and software-defined vehicles, this reference design provides a compact, efficient, and highly integrated solution for automotive Ethernet connectivity and power delivery.
TI has tested this reference design. It comes with a bill of materials (BOM), schematics, assembly drawing, printed circuit board (PCB) layout, and more. The company’s website has additional data about the reference design. To read more about this reference design, click here.
