MSD1278-333ML

Document 499-1 Coupled Inductors–MSD1278 For SEPIC and other Applications The excellent coupling coefficient (k ≥ 0.94) makes the MSD1278 series of coupled inductors ideal for use in SEPIC applications. In SEPIC topologies, the required inductance for each winding in a coupled inductor is half the value needed for two separate inductors, allowing selection of a part with lower DCR and higher current handling. These inductors provide high inductance, high efficiency and excellent current handling in a rugged, low cost part. They are well suited for use as a VRM inductors in high-current DC-DC converters and VRM/ VRD controllers. They can also be used as two single inductors connected in series or parallel, as a common mode choke or as a 1 : 1 transformer. 0.484 max 12,3 D1 + L1 C1 Dot indicates pin1 Dash number Internal code Parts manufactured prior to Sept. 2007 were marked with only the dash number. + + VOUT 0.484 max 12,3 123 X VIN Q1 L2 C2 Load – – Typical SEPIC schematic 0.317 max 8,05 Refer to Application Note, Document 639, “Selecting Coupled Inductors for SEPIC Applications” Recommended Land Pattern 0.197 5,0 0.138 3,5 0.197 5,0 3 2 4 1 0.217 5,5 0.157 4,0 2 3 1 4 0.177 4,5 0.059 1,5 0.079 2,0 Dimensions are in inches mm 1 L1 3 2 L2 4 Designer’s Kit C400 contains 3 each of all values. Core material Ferrite Terminations RoHS compliant matte tin over nickel over phos bronze. Other terminations available at additional cost. Weight: 3.7 – 4.4 g Ambient temperature –40°C to +85°C with Irms current, +85°C to +125°C with derated current Storage temperature Component: –40°C to +125°C. Packaging: –40°C to +80°C Winding to winding isolation 500 Vrms Resistance to soldering heat Max three 40 second reflows at +260°C, parts cooled to room temperature between cycles Moisture Sensitivity Level (MSL) 1 (unlimited floor life at