CANbus voltage refers to the electrical voltage levels used in the Controller Area Network (CAN) protocol, which is a widely used communication standard in automotive and industrial applications. The CAN protocol allows different electronic control units (ECUs) within a system to exchange data and communicate with each other.
CANbus operates with two voltage levels: dominant and recessive. The dominant level represents a logical '0', while the recessive level represents a logical '1'. These voltage levels are defined by the CAN standard and are typically implemented using differential signaling.
In a CANbus system, the dominant level is achieved when the voltage difference between the two CANbus lines is around 2.5 volts, with one line being pulled to a higher voltage level and the other pulled to a lower voltage level. This level is considered dominant because it overpowers the recessive level.
On the other hand, the recessive level is achieved when the voltage difference between the two CANbus lines is close to zero or within a defined tolerance range. In this case, both lines are at the same voltage level, which is typically around 2.5 volts. This level is considered recessive because it does not overpower the dominant level.
The specific voltage levels for dominant and recessive states may vary slightly depending on the CAN specification being used. The two most common CAN specifications are CAN 2.0A and CAN 2.0B. In CAN 2.0A, the dominant voltage level is between 2.5 and 3.5 volts, while the recessive voltage level is between 1.5 and 2.5 volts. In CAN 2.0B, the dominant voltage level is the same, but the recessive voltage level is between 2.0 and 3.0 volts.
It's important to note that the CANbus voltage levels are differential voltages, meaning they represent the voltage difference between the two CANbus lines, rather than absolute voltage values. This differential signaling helps to improve noise immunity and allows for longer communication distances.
Overall, CANbus voltage refers to the specific electrical voltage levels used in the CAN protocol to represent logical states and facilitate reliable communication between different devices within a CAN network.
