CAN bus

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Controller Area Network

Type	Serial communication bus
Production history
Designer	Bosch GmbH
Designed	1983; 41 years ago (1983)
External	No
Electrical
Signal	Differential
Max. voltage	16V DC
Data
Data signal	Transceiver driven
Width	1 bit (bidirectional)
Bitrate	0.05, 0.125, 0.250, 0.500, 0.800 or 1.0 Mbit/s, up to 5.0 Mbit/s for CAN FD
Max. devices	32, 64 or 127 (depending on standard)
Protocol	Serial, half-duplex, Asynchronous
Pinout
CAN-H	CAN High (Yellow)
CAN-L	CAN Low (Green)

A controller area network (CAN) is a vehicle bus standard designed to enable efficient communication primarily between electronic control units (ECUs). Originally developed to reduce the complexity and cost of electrical wiring in automobiles through multiplexing, the CAN bus protocol has since been adopted in various other contexts. This broadcast-based, message-oriented protocol ensures data integrity and prioritization through a process called arbitration, allowing the highest priority device to continue transmitting if multiple devices attempt to send data simultaneously, while others back off. Its reliability is enhanced by differential signaling, which mitigates electrical noise. Common versions of the CAN protocol include CAN 2.0, CAN FD, and CAN XL which vary in their data rate capabilities and maximum data payload sizes.