CAN repeater or bridge? Which device is more suitable for my CAN network?

09 May 2025

This article compares the CAN-Repeater with the CANbridge devices.

 

APPLICABLE PRODUCTS

CANrepeater, CAN-CR200, CAN-CR210/FO, CAN-CR220, CAN-CR100, CAN-CR110/FO, CAN-CR120/HV, CAN-CR300, CAN/FD Repeater Standard, CANbridge NT 200, CANbridge NT 420.

 

QUESTION

CAN-Repeater or CANbridge? Which device is more suitable for my CAN network? 

 

ANSWER

CAN-Repeater can be used for the physical coupling of two or more segments of a CAN-Bus system. CAN networks have a bus (line) topologies, but using CAN-Repeater tree and star topologies and long branches are realizable. The CAN-Repeater splits the CAN network in two galvanic isolated networks and works bit-wise. It means that all CAN nodes in the different segments receive the same bit information. Electrical each segment presents a CAN Bus (line). A CAN Repeater can not extend the CAN-network because of its delay time that has an effect like an additional line. It is more suitable for adaption to the available topography, for the galvanic isolation of network segments and to increase the number of possible nodes. CAN-Repeater and Star Coupler do not influence the real-time behavior of the system, because the transfer behavior complies with one network. Using CAN repeaters, the distance between the two furthermost CAN nodes must not be larger than the maximal CAN bus length for the used CAN baud rate.

CAN-Bridges and CAN-Gateways are infrastructure components that can be used to implement a complex network structure. CAN-Bridges can connect CAN networks with different Bitrates or Modes. The CANbridge is based on so-called Store-(Modify)-Forward principle. It receives CAN messages and forwards them to another CAN segment under consideration of possible filter or transform rules. The CANbridge allows the extension of the maximal network length, because the sections of the CAN system are independent in relation to the bus arbitration. With the CAN-Bridges connected CAN subnetworks are independent CAN networks and have an independent real-time behavior.