What is a drum core?

A drum core consists of ferrite material and is named after its shape. Although resembling a drum, its physical size is a thousand times smaller than that of an actual musical drum. The drum core has two flat discs on its ends. The center post is narrower to keep the wires between the two ends. Due to the feature of the air gap flux path, a drum core can carry a higher current than a toroidal core without saturation. With this characteristic, a drum core is preferably designed for power inductors.

How to SELECT a drum core inductor for the application?

Three main parameters need to be considered in selecting a drum core inductor:

1. Inductance
2. Rated current
3. DC resistance

Inductance at rated current is the most critical parameter that is determined by the users for their application. .

If a Drum Core Cannot Be Found,

If the inductance at rated current cannot be found in the drum core product range, the next alternative solution is to look for other inductor product families that are used a larger toroidal or E core with materials of iron powder, Kool-Mu, or MPP.