Ferrite beads has been very helpful in filtering high frequency noise. However, improper use of ferrite beads in system design can lead to some issues. One thing to consider is the response characteristic as this will determine the bead inductance. The DC bias current is another parameter to consider as current through the bead will change the inductance. Another is the LC resonance as peaking occurs when the bead is used with the decoupling capacitor. This can harmful if not accounted carefully since it will amplify ripple and noise at resonant frequency. Damping methods should be considered next. For more information in using ferrite beads, please check “Ferrite Bead Demystified” application note in analog.com
