An opto-emulated switch such as ISOM8610 can be used in CAN node design applications. The ISOM8610 enables a software configurable termination on the CAN bus, needed in networks where new nodes can be continually added. This design can enable or disable termination across CANH-CANL by driving TERM high or low (with appropriate current limiting series resistor on LED emulator pins) through GPIO of the MCU.

With this architecture, 60Ω effective termination across the CAN bus can be achieved with flexibility on enabling/disabling a node, with no hardware change. The Top Design Questions About Isolated CAN Bus Design application note contains top answers to design questions about Isolated CAN Bus designs. Finally, the ISOM8610 can be used as an 80V isolated switch when used within the Recommended Operating Conditions.

Figure 4-4 Typical Software-Controlled Termination Using the ISOM8610