The basics of the controller area network (CAN bus) and its use in automotive applications By Art Pini
Figure 1: The data bus connections in a typical vehicle implemented with CAN and LIN network elements. (Image source: Texas Instruments)
In-vehicle networks (IVNs) allow microcontrollers and engine control unit (ECU) processors to communicate with sensors, actuators, indicators, displays, and each other. The network bandwidth for IVNs depends on the function being supported. Typically basic body and comfort applications work fine with very low bus bandwidth, power-train and chassis applications require a little more bandwidth, safety features use medium bandwidth, infotainment applications use high bandwidth, while advanced driver assistance systems (ADAS) require very high bandwidth.
Also, IVNs can use multiple network architectures, each matched with a group of functional needs. One of the classic IVNs is the Controller Area Network or CAN bus. Let’s take a look at it, and some example CAN bus transceivers from Texas Instruments.
of up to 1 megabit per second (Mbps) and handles medium bandwidth requirements. The bus routing for a typical vehicle involves a great many connections. Figure 1 shows the large number of connections typical of modern vehicles. In this example, the CAN bus is linked to a lower-speed, local interconnect network (LIN) that operates at data rates of up to 20 kilobits per second (kbps), and is cost- effective for low-bandwidth needs.
CAN bus capabilities and structure
CAN has been around for about thirty years and continues to evolve. The classic CAN bus is described in the ISO11898 standard. It supports data rates
The high cost and weight of a wiring harness in a vehicle means the implications of a
we get technical
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