How to filter out power line spike interference in a power supply DTU?

Filtering power line spike interference from the DTU requires a multi-stage protective filtering network. The first stage uses a 2R600L-8×6 gas discharge tube to absorb high-energy spikes; the second stage uses a 14D511K varistor to clamp medium-energy spikes; and the third stage uses an SMCJ24CA TVS diode to handle low-energy fast spikes. The filtering section uses an LC low-pass filter, with a PWR6045R6R8M0T power inductor and two safety-rated capacitors (0.47μF). The spike suppression effect is analyzed through simulation, and parameters are optimized. In actual testing, the system should be able to withstand a 1.2/50μs-8/20μs combined wave test (±4kV). Filtering out spike interference protects the internal circuitry and improves reliability.