Tolerance
• % deviation from the
nominal inductance value specified by
the manufacturer
• Usually designated by
a tolerance letter
Direct Current Resistance (DCR)
• Resistance of the
inductor winding while passing DC current
• Most often minimized
by manufacturers and listed as a maximum rating
Incremental Current
• DC current causing
the inductance to drop 5% of its normal
value
• Loses even more
inductance, the more current is applied
• Characteristic found
in ferrite cores
• Rate of inductance
drop is also a function of core shape
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