Automotive Ethernet Interface Basics
Automotive Ethernet Interface Basics: In this article, we’ll revisit how Automotive Ethernet interfaces work and provide an overview of its various types, highlighting their key differences and applications. BLOCK DIAGRAM : Image Reference OPEN Alliance MDI (Media Dependent Interface): MDI defines how signals are transmitted and received over Ethernet cables, especially in automotive networks using Single-Pair Ethernet PHY (Physical Layer) Chip : The signal from the PHY chip is transmitted over twisted-pair cables. DC Blocking / AC Coupling Capacitor : Placed in series between the PHY and the Ethernet cable to block any DC bias and protect the system. AC Coupling is realized by 100nF Coupling Capacitor to form a high pass filter together with 50Ohm termination on each line. Signal Integrity : The capacitor ensures that only the desired AC signal (which carries data) is passed to the PHY, while any DC bias is blocked. CMC (Common Mode Choke) is used to reduce electromagneti...