# inductor derating

I am designing a system with a lot of documentation. One of the things I need to do is do a derating analysis of the components. I am henceforth, trying to derate the inductors in my circuit. Mainly, I am using inductors in the switching power supply sections and some of the RF sections. Now, I understand that the main parameters of inductors are the ESR and the current rating. Hence-forth, I will simulate the system and check if the selected inductors suffice. Now, how do I derate these properties? One of the main factors being temperature. When the temperature varies some of these properties change. How does temperature these properties and which properties does it vary(have an effect)? For eg, consider the pic below from the website - Derating of inductors Here-in, it shows different load type and the derating factor. It states ,for eg 70% of rated resistive load. What does it exactly mean ? Imagine , I use an inductor of 1nH, then applying the above rule, what are the implications on this 1nH value ? Or is the implications on the current carrying capanility with the inductance value remaining constant ?

## 1 Answer

That table is not for Inductors, but for Relays. It's been mislabled apparently. The parameters for Load types: Resistive Load, Capacitive Load, Inductive Load don't make sense for inductors.

Inductors are derated by "Hot spot temperature" (30$^\circ$C Below Specified Maximum Insulation Rating) and "Peak Flux Density" (70% of Saturation).

You might check NAVSO P3641A for a table of component deratings.