CAN Bus PCB Routing – Two Nodes with Unequal Distance to Single Connector

Design and Layout
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Hi Friends,

I am working on a PCB design with the following CAN architecture:

  • Two MCUs on the same board

  • Each MCU has its own CAN transceiver

  • Both transceivers are connected to a common CANH and CANL connector (single CAN bus)

The challenge I am facing is related to routing:

  • One transceiver is placed very close to the connector

  • The other transceiver is approximately 30 cm away from the connector

My understanding from CAN layout guidelines is:

  • CAN should follow a linear bus topology

  • Nodes should be connected using short stubs

  • Long stubs can cause signal reflections and integrity issues, especially at higher bit rates

In this scenario, what is the recommended routing approach?

  1. Should I treat the 25 cm trace as a stub (which seems too long )?

  2. Or should I route a main CAN bus line across the PCB (from the far transceiver → near transceiver → connector), and connect both transceivers inline to this bus?

    Regarding termination:

    • Should I place a single 120Ω termination resistor for the entire bus (only if the board is at the end)?

    • Or should each transceiver have its own termination resistor?