EFD Cores (8978202021)Part Number: 8978202021
78 EFD CORE SET
EFD (Economical Flat Design) cores have been designed to maximize volume in a low profile geometry. EFD cores allow maximum throughput power density with reasonably low mass for board level installation.
EFD cores can be supplied with the center post gapped to a mechanical dimension or an ALvalue.
Weight indicated is per pair or set.
Weight: 7 (g)
| Dim | mm | mm tol | nominal inch | inch misc. |
| A | 20 | ± 0.55 | 0.787 | _ |
| B | 10 | ± 0.25 | 0.394 | _ |
| C | 6.65 | ± 0.20 | 0.262 | _ |
| D | 7.7 | ± 0.25 | 0.303 | _ |
| E | 15.4 | ± 0.50 | 0.606 | _ |
| F | 8.9 | ± 0.30 | 0.35 | _ |
| K | 3.6 | ± 0.15 | 0.142 | _ |
Chart Legend
Σl/A : Core Constant, le : Effective Path Length, Ae : Effective Cross-Sectional Area, Ve : Effective Core Volume
AL : Inductance Factor 
Explanation of Part Numbers: Digits 1 & 2 = product class and 3 & 4 = material grade.
| Electrical Properties | |
| AL(nH) | 1200 ±25% |
| Ae(cm2) | 0.31 |
| Σl/A(cm-1) | 15.6 |
| le(cm) | 4.74 |
| Ve(cm3) | 1.44 |
| Amin(cm2) | 0.29 |
AL value is measured at 1 kHz, B < 10 gauss.