This page has a mistake for the LC filter configuration:
/www.digikey.com/en/resources/conversion-calculators/conversion-calculator-low-pass-and-high-pass-filter
Remove forward slash (/) at the beginning in the above link.
The equation given for the -3 dB cutoff frequency (for the LC filter) is incorrect. The equation given on the page is the resonant frequency, not the -3 dB cutoff frequency. I made a plot that shows this:
When someone selects LC filter, I recommend two changes:
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In “LC Filter Formulas”, change f꜀ to fᵣ.
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Change “-3dB Cutoff Frequency” to “Resonant Frequency”
If you would like more information on this, including a derivation of the -3 dB cutoff frequency, please send me an email at michael79749 at yahoo.com.
Thank you,
Michael Craft