Switching frequency for inductor


For the indictor “L201204-102MHF”, the “Inductance Frequency - Test is 10 kHz”. What does this mean. I want to use this inductor for a DC-DC converter where I want to have the switching frequency of 100kHz. Will this inductor work?


The test frequency listed for an inductor is the signal frequency at which the listed device characteristics are measured.

All inductors display some degree of parasitic capacitance between their windings; as signal frequency increases this parasitic element becomes more and more significant, up to a point known as the self-resonant frequency (SRF) at which the inductor ceases to electrically behave much like an inductor at all. For obvious reasons, one usually prefers to operate well below an inductor’s SRF.

Since the manufacturer of the part is question was not so kind as to provide a characterization of it’s SRF, one’s pretty much stuck with acquiring a sample and measuring it oneself. A mH is quite a bit of inductance however, and in general high L values don’t usually correlate with high SRF values. It might be OK, but my inclination would be to look for other solutions.

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