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TCAN1042H: Is it possible that the GND pin of TCAN1042H left floating?

Part Number: TCAN1042H

Hi team,

My customer wants to know if they can left the GND pin of TCAN1042 floated, while only CAN_H and CAN_L are linked out to the bus, as shown in the following figure,

The isolated power is powering TCAN1042 via Vcc and STB, they want to remove the 0ohm resistor linked with isolated GND. The only CANH and CANL will be linked outside. They need this kind of process to be compatible with other products. For this case, can you advise whether there is any risk and what other things they can do (optimize layout, etc) to ensure the performance?



  • Xiaoying,

    Our CAN transceivers are actually tested against ground shifts in the system to verify that communication will maintain even if there is a mismatch in GNDs between nodes. Since the TCAN1042 devices have a common-mode range of +/-30V, the CANH and CANL differential signal can vary in that range and still be correctly received by the transceiver. The only risk is if a ground shift causes the VCC voltage to hit the undervoltage threshold. However, since this system is isolated from the main GND, I don't think that should be a problem.

    Just to clarify, the GND pin and the STB pin are connected to a GND, it's just not connected to the CAN GND, is that right?


    Eric Hackett 

  • Hi Eric,

    Yes, it's just not connected to the CAN GND. Thanks for your explanation!