How to prevent crosstalk when multiple buses coexist in a motion controller (MC)

Preventing crosstalk between multiple buses within a motion controller (MC) requires addressing frequency planning, spatial isolation, and filtering. First, if possible, stagger the operating clock frequencies of different buses to avoid harmonic overlap. On the PCB layout, separate the physical interfaces and transceiver circuits of different buses into distinct areas, separated by grounding shields or isolation channels. Provide independent ferrite bead filters for the power supply of each bus.

During routing, maintain sufficient spacing between signal lines of different buses, avoiding long parallel traces. Add common-mode chokes at their respective ports to suppress noise radiation from the bus and enhance immunity to external interference. Use shielded cables and ensure the shielding layer is properly grounded at the controller end. Scan with a near-field probe to detect the field strength in different bus circuit areas, ensuring no significant coupling. During system operation, simultaneously activate all buses and test the bit error rate or delay of each bus communication to verify the effectiveness of the anti-crosstalk measures.