Metal composite inductors - do they make ferrite inductors an anachronism for good?

RE: Metal composite inductors - do they make ferrite inductors an anachronism for good?

moritzcehak — Tue, 16 Feb 2021 09:39:13 GMT

Dear James,

You raised an interesting question and indeed as always in engineering there are trade-offs.

One trade-off is the high frequency behavior. Metal-composite inductors generate higher losses around frequencies above 5 MHz. However, Panasonic for example just recently launched a new series which also is overcoming this weakness, called ETQP***HF* series (see for example Automotive power inductors | Panasonic Industry Europe GmbH). But if it comes above 10MHz, ferrite can keep their performance better due to magnetic characteristic. Currently, this is still a niche-application and we are optimistic to keep track with our development.

Another trade-off is as you mention the pricing: Ferrites are a commodity material with a wide range of suppliers, high availability and an easy manufacturing process. So when you compare the same case size between metal composite and ferrite, you might always find a cheaper version.

However, if you compare the details of the datasheet or specification, you may recognize in many application that using a metal-composite inductor is the better choice because of downsizing, lower leakage and higher efficiency. And in the end the price of an inductor itself has to be seen in the total picture of the PCB layout and board performance (quality, robustness, performance, space saving, etc.), which a designer must consider in her/his process.

Your sincerely.

Panasonic team.

RE: Metal composite inductors - do they make ferrite inductors an anachronism for good?

Gough Lui — Thu, 11 Feb 2021 21:02:10 GMT

I suspect you meant "do they make ferrite INDUCTORS an anachronism for good", as I've never heard of a ferrite capacitor before ...

- Gough

RE: Metal composite inductors - do they make ferrite inductors an anachronism for good?

baldengineer — Thu, 11 Feb 2021 20:32:44 GMT

Interesting comparison. As always in engineering, there are trade-offs. Certainly, there is some trade-off to use a metal composite inductor. Mechanically, they look denser/smaller than their ferrite cousin. Are there any electrical performance trade-offs? (Any cases where ferrite would perform better?)

Or it is a case of cost? (and if that is the case, is it just a matter of time until their volumes are higher so there is even less of a price difference?)

Also, I always wondered about metal composites, how are they manufactured? Is the composite material sintered?