F Flyback Well-Known Member Mar 1, 2021 #1 At what frequencies do clip on cable ferrites have an effect? <30MHz?, >30MHz?, >100MHz? >200MHz, >1GHz? I speak of such ferrites for clipping on to dc cables which are coming out of isolated offline SMPS containing enclosures.
At what frequencies do clip on cable ferrites have an effect? <30MHz?, >30MHz?, >100MHz? >200MHz, >1GHz? I speak of such ferrites for clipping on to dc cables which are coming out of isolated offline SMPS containing enclosures.
rjenkinsgb Well-Known Member Most Helpful Member Mar 1, 2021 #2 They typically have some effect from relatively low frequencies; it's an increase in impedance, so the attenuation also depends on other factors, as well as the core material. eg. These all give maximum attenuation at very different frequencies:
They typically have some effect from relatively low frequencies; it's an increase in impedance, so the attenuation also depends on other factors, as well as the core material. eg. These all give maximum attenuation at very different frequencies:
crutschow Well-Known Member Most Helpful Member Mar 1, 2021 #3 Generally the larger the ferrite, the lower the frequency for significant attenuation. You might also consider common-mode chokes to suppress the SMPS noise.
Generally the larger the ferrite, the lower the frequency for significant attenuation. You might also consider common-mode chokes to suppress the SMPS noise.