Overview
ISO 11898-2:2026 specifies the physical medium attachment (PMA) sublayer requirements for the Controller Area Network (CAN) in road vehicles, with a focus on high-speed (HS) operation. The standard provides the technical foundation for reliable CAN communication by defining the electrical characteristics, behaviors, and interfaces necessary for HS-PMA implementations. It addresses the requirements for standard HS CAN, low-power mode functionality, selective wake-up, and new operational modes such as Signal Improvement Capability (SIC) and FAST mode, supporting the evolving demands of advanced vehicle networks.
This standard ensures industry-wide interoperability and robustness for high-speed CAN transceivers, which are critical to automotive communication for functions ranging from powertrain control to advanced driver-assistance systems (ADAS).
Key Topics
- High-Speed PMA Requirements: Defines the transmitter and receiver behavior, including differential signaling and voltage characteristics for CAN_H and CAN_L lines, necessary to achieve robust high-speed CAN communication.
- Operation Modes:
- Normal-Power Mode: Full communication capability.
- Low-Power Mode: Reduced power consumption with provisions for wake-up detection and signaling.
- Selective Wake-up: Ability for specific nodes to re-activate based on addressable CAN messages, supporting partial networking.
- Advanced Features:
- Signal Improvement Capability (SIC): Enhances signal quality and suppresses electrical ringing, improving CAN network reliability in challenging conditions.
- FAST Mode: Offers higher performance profiles and specific receiver/transmitter threshold adjustments for advanced use cases.
- Electrical Parameter Definitions: Includes detailed boundaries for voltage, current, impedance, timing, and symmetry to guarantee EMC compatibility and prevent bus contention.
- Interfacing: Specifies the attachment unit interface (AUI) signals (TXD, RXD, GND) linking the PMA to the upper physical coding sublayer (PCS).
- Testing and Conformance: Outlines test circuits, methods, and conformance requirements to validate implementations over a range of operational and environmental conditions.
Applications
ISO 11898-2:2026 is integral to automotive network design and implementation, especially where high-speed and reliability are critical. Common practical applications include:
- Automotive Electronic Control Units (ECUs): Ensures compatibility and robust communication between ECUs for functions such as engine management, braking, stability control, and infotainment.
- Partial Networking: Facilitates energy-efficient designs by allowing ECUs to enter low-power states and wake up selectively, contributing to reduced vehicle standby power consumption.
- Advanced Driver-Assistance Systems (ADAS): Supports the increased data exchange demands of modern vehicle safety and autonomous features with high-speed, low-latency communication.
- Aftermarket and Diagnostic Tools: Provides standardized electrical and signaling characteristics, ensuring that tools can safely connect and reliably communicate with in-vehicle CAN networks.
- Commercial and Heavy Vehicles: Extends high-speed CAN applicability to trucks, buses, and specialized vehicles where reliable, high-speed communication is vital.
Related Standards
- ISO 11898-1: Road vehicles - Controller area network (CAN) - Part 1: Data link layer and physical coding sublayer. Provides specifications for CAN protocol controllers and the link to the PMA defined in ISO 11898-2.
- ISO/IEC 7498-1: Information technology - OSI Basic Reference Model. Establishes the Open Systems Interconnection (OSI) architecture referenced by CAN physical and data link layers.
- ISO 16845 Series: CAN conformance test plans. Essential for ensuring implementations of ISO 11898-2 meet required operational and interoperability standards.
- Other Parts of ISO 11898 Series: Such as ISO 11898-3 (fault-tolerant CAN), collectively forming the comprehensive framework for CAN network implementation.
By following ISO 11898-2:2026, automotive system designers and component manufacturers can ensure efficient, reliable, and future-ready CAN communications for high-speed, energy-efficient, and scalable vehicle architectures. This standard is vital for meeting modern and upcoming automotive network requirements.
Open preview (PDF)Road vehicles — Controller area network (CAN) — Part 2: High-speed physical medium attachment (PMA) sublayer