Ferrites and accessories EFD 20/10/7 Core and accessories Series/Type: B66417, B66418 Date: June 2013 Data SheetData Sheet EPCOS AG 2015. Reproduction, publication and dissemination of this publication, enclosures hereto and the information contained therein without EPCOS prior express consent is prohibited. EPCOS AG is a TDK Group Company. EFD 20/10/7 Core B66417 E core with flattened, lower center leg for especially flat transformer design For DC/DC converters Delivery mode: single units Magnetic characteristics (per set) 1 l/A = 1.52 mm l = 47 mm e 2 A = 31 mm e 2 A = 31 mm min 3 V = 1460 mm e Approx. weight 7.2 g/set Ungapped Material A value P Ordering code L e V nH W/set N49 910 +30/20% 1100 < 0.29 ( 50 mT, 500 kHz, 100 C) B66417G0000X149 N87 1200 +30/20% 1440 < 1.05 (200 mT, 100 kHz, 100 C) B66417G0000X187 N97 1250 +30/20% 1510 < 0.80 (200 mT, 100 kHz, 100 C) B66417G0000X197 Gapped Material A value g Ordering code L e nH approx. mm N87 100 10% 120 0.49 B66417U0100K187 160 10% 193 0.25 B66417U0160K187 The A value in the table applies to a core set comprising one ungapped core (dimension g = 0) and L one gapped core (dimension g > 0). Calculation factors (for formulas, see E cores: general information ) Material Relationship between Calculation of saturation current air gap A value L K1 (25 C) K2 (25 C) K3 (25 C) K4 (25 C) K3 (100 C) K4 (100 C) N87 61.1 0.699 85.4 0.796 75.7 0.873 Validity range: K1, K2: 0.10 mm < s < 1.40 mm K3, K4: 50 nH < A < 410 nH L Please read Cautions and warnings and 2 06/13 Important notes at the end of this document.