How to avoid resonance in multi-stage filtering of power DTU?

To avoid resonance in multi-stage DTU filters, a damping design and frequency staggering strategy are required. A small resistor (1-10Ω) is connected in series or a damping resistor (10-100Ω) is connected in parallel within the LC filter network to reduce the Q value. The cutoff frequencies of each filter stage are staggered, for example, the first stage is set at 10kHz, the second at 100kHz, and the third at 1MHz. A PBZ1608A-102Z0T ferrite bead is used as a high-frequency damping component. Circuit simulation analysis of the system frequency response ensures no resonance spikes in the 10Hz-30MHz range. In actual measurements, using a network analyzer, the gain fluctuation should be less than 3dB. Avoiding resonance prevents signal amplification and EMI degradation, improving system stability.