EFD 20/10/7 Core B66417 ● E core with flattened, lower center leg for especially flat transformer design ● For DC/DC converters ● EFD cores are supplied as single units Magnetic characteristics (per set) Σl/A le Ae Amin Ve = 1,52 mm–1 = 47 mm = 31 mm2 = 31 mm2 = 1 460 mm3 Approx. weight 7,2 g/set Ungapped µe Material AL value AL1min PV N49 nH nH 910 + 30/– 20 % 1100 750 N87 1200 + 30/– 20 % 1440 660 Ordering code W/set 0,29 B66417-G-X149 (50 mT, 500 kHz, 100 ˚C) 1,05 B66417-G-X187 (200 mT, 100 kHz, 100 ˚C) Gapped Material AL value µe N87 nH 100 ± 10 % 160 ± 10 % 120 193 g approx. mm 0,49 0,25 Ordering code B66417-U100-K187 B66417-U160-K187 The AL value in the table applies to a core set comprising one ungapped core (dimension g = 0) and one gapped core (dimension g > 0). Calculation factors (see page 423 for formulas) Material N87 Validity range: 552 Relationship between air gap – AL value K1 (25 ˚C) K2 (25 ˚C) 61,1 – 0,699 Calculation of saturation current K3 (25 ˚C) 85,4 K4 (25 ˚C) – 0,796 K3 (100 ˚C) K4 (100 ˚C) 75,7 – 0,873 K1, K2: 0,10 mm < s < 1,40 mm K3, K4: 50 nH < AL < 410 nH Siemens Matsushita Components EFD 20/10/7 Accessories B66418 Coil former Material: GFR thermosetting plastic (UL 94 V-0, insulation class to IEC 60085: F max.operating temperature 155 ˚C), color code green Solderability: to IEC 60068-2-20, test Ta, method 1 (aging 3): 235 ˚C, 2 s Resistance to soldering heat: to IEC 60068-2-20, test Tb, method 1B: 350 ˚C, 3,5 s Winding: see page 156 Squared pins Yoke ● Material: Stainless spring steel (0,3 mm) Coil former Ordering code Sections AN mm2 lN mm AR value µΩ Pins 1 28,1 40,2 49,2 8 Yoke (ordering code per piece, 2 are required) Coil former B66418-B1008-D1 B66418-B2000 Yoke View A Mounting holes Marking of pin 1 CuSn6, tinned Siemens Matsushita Components 553