Inductor selection criteria
Inductor selection criteria
(OP)
I need to select an inductor to be used in a 10 kHz circuit. It will be used in a series resonant circuit where the A.C. current can be as high as 200 mA. I notice that most of the inductors of the type I would like to use have a D.C. current rating. There will be no D.C. current flowing in this circuit. However, the A.C. current exceeds the D.C. current rating. Will this be a problem?





RE: Inductor selection criteria
RE: Inductor selection criteria
RE: Inductor selection criteria
RE: Inductor selection criteria
RE: Inductor selection criteria
If you can not find one there the easiest way is to wind one yourself on a ferrite core.
RE: Inductor selection criteria
Just explanation, why producers if inductors give data of saturation current in DC value (despite that in real circuits usually appears AC signal): it is much easier to measure inductance with small AC signal, superimposed to large DC signal, when measuring saturation values - and these measurements are pretty identical like if it was pure large AC signal applied. Data for saturation DC current is then equal to maximum (peak) value of AC current thrue inductor.
And as you know, if current exceeds saturation limit value, inductance of inductor with core starts to decrease.
Best regards, Jmarko
RE: Inductor selection criteria
http://www.linear.com/pub/document.html?pub_type=app&document=90
They specialize in switching regulators and I've found this particular app note #19 as especialy helpful.
Good example on page 4
Good Luck