Therefore, it would be reasonable to expect low-pass behavior at switching converter frequencies. When placed between a power regulator circuit output and the bypass capacitor on input power pins for a digital component, you have basically formed a Pi filter. Why Ferrite Beads Should Not Be Used to Prevent Digital Power Rail Ripple If you do use ferrites for filtering on the output side of a power converter, the acceptable use of these components depends on what you need them to do. Placing these components on the input section of a power stage is much more effective than placing them on the output side. Coupled choke coils specifically targeting common-mode or differential mode noiseįerrite clamps used to filter noise on input power lines.
Inductors to provide low-pass filtering of input EMI.A ferrite bead within a voltage regulator to provide some switching noise compensation.