ETD cores have been designed to make optimum use of a given volume of ferrite material for maximum throughput power, specifically for forward converter transformers. Their structure, which includes a round center post, approaches a nearly uniform cross-sectional area throughout the core and provides a winding area that minimizes winding losses. ETD cores are used mainly in switched-mode power supplies and permit off-line designs where IEC and VDE isolation requirements must be met.

• Part number is for a single core.

• ETD cores can be supplied with the center post gapped to a mechanical dimension.

• ETD cores can also be gapped to an AL value. These cores will be supplied as sets.

• AL value is measured at 1kHz, <10 gauss.

• See section "The Effect of Direct Current on the Inductance of a Ferrite Core" for curves of AL vs. gap length.

• The ETD cores are in conformance with IEC 61185.

• Explanation of Part Numbers: Digits 1&2 = product class, 3&4 = material grade.