How to suppress the interference of the switch input in the intelligent low-voltage monitoring unit?

Interference suppression for digital inputs employs hardware filtering and software debouncing. Hardware: RC filter (10kΩ + 100nF), time constant 1ms. A parallel ESD 5V0D8B bidirectional ESD protection device is connected to the input port. Shielded twisted-pair cable is used for signal lines. PCB layout: Digital input circuitry is centrally located, away from interference sources. Optical isolation, such as TLP281, is used. Software debouncing: Resampling is performed after a 10ms delay. Through this suppression, the immunity to interference from digital inputs is improved, with a false positive rate of less than 0.01%.