How to eliminate mutual interference between multiplexers in a power FTU?

Interference between multiple switches occurs through power supply coupling and magnetic field coupling. The solution is as follows: Each switch uses an independent driver power supply (WRB2405S-3W). Shielded twisted-pair cables are used for the switch signal lines, with the shield grounded at a single point. On the PCB, the driver circuits for each switch are laid out in separate zones with a spacing greater than 15mm and a grounding guard ring in between. A PBZ1608E600Z0T ferrite bead (600Ω@100MHz) is installed at each power input. In terms of software, the operation times of each switch are staggered with an interval greater than 10ms. This design reduces switch interference by more than 40dB, allowing each switch to operate independently and meeting the IEC 61000-4-6 conducted immunity 10V test requirements.