What is ISO 11898 standard

The ISO 11898 standard, also known as Controller Area Network (CAN), is a widely adopted communication protocol used in various industries, including automotive, industrial automation, and medical devices. It provides a reliable and efficient method for data transmission between electronic control units (ECUs). The standard specifies the physical and data link layer requirements for the CAN bus system, enabling seamless communication between different devices.

Physical Layer Requirements

The physical layer of the ISO 11898 standard defines the electrical characteristics necessary for proper signal transmission over the CAN bus. It specifies the voltage levels, signaling rate, cable impedance, and termination requirements. The differential signaling used in the CAN bus provides high noise immunity, allowing for reliable communication in harsh industrial environments. The standard also defines the physical connector and pinout arrangements, ensuring compatibility between different devices and systems.

Data Link Layer Requirements

At the data link layer, the ISO 11898 standard specifies the format for messages exchanged on the CAN bus. It defines the structure of the message, including the identifier field, data field, and error checking mechanisms. The standard supports two different frame formats: the Standard Frame Format (SFF) and the Extended Frame Format (EFF). The SFF allows for 11-bit identifiers, while the EFF extends it to 29 bits, providing a larger address space for more devices to coexist on the network. Additionally, the standard includes error detection and fault confinement mechanisms to ensure reliable data transfer.

Advantages and Applications

The ISO 11898 standard offers several advantages that make it widely adopted in various industries. Its high reliability, low latency, and fault tolerance capabilities are crucial for safety-critical applications, such as automotive control systems. The CAN bus provides a cost-effective solution for connecting multiple ECUs, reducing wiring complexity and weight in vehicles. Additionally, the standard allows for easy integration of different devices from multiple vendors, promoting interoperability and scalability. Its wide range of applications includes vehicle diagnostics, industrial control, medical equipment, and many more.