Document 616 Toroidal Transformer – Q3903-AL • Specified by ON Semiconductor for use with their NCP1605 PFC Controller. Referenced as X25, pulse transformer on evaluation board NCP1605FORWGEVB and Application Note AND8292. • Recommended by Texas Instruments for use with their UC3875 Phase Shift Resonant Controller. • Three 1 : 1 windings • 500 Vrms, one minute winding-to-winding isolation. Core material Ferrite Terminations RoHS compliant tin-silver over tin over nickel over brass. Other terminations available at additional cost. Weight 4.3 g Ambient temperature –40°C to +85°C Storage temperature Component: –40°C to +85°C. Tray packaging: –40°C to +80°C Moisture Sensitivity Level (MSL) 1 (unlimited floor life at <30°C / 85% relative humidity) Failures in Time (FIT) / Mean Time Between Failures (MTBF) 38 per billion hours / 26,315,789 hours, calculated per Telcordia SR-332 Packaging 49 per tray PCB washing Tested with pure water or alcohol only. For other solvents, see Doc787_PCB_Washing.pdf Part Inductance1 DCR max2 number min (µH) (Ohms) Q3903-AL 210 0.090 Inter-winding isolation (Vrms) 500 1. Inductance measured between pins 1 and 6, at 15.75 kHz, 0.015 Vrms, 0 Adc using an Agilent/HP 4192A impedance analyzer. 2.DCR is per winding, measured on Cambridge Technology microohmmeter or equivalent. 3. Electrical specifications at 25°C. 1 Notch indicates pin1 1 6 2 5 3 4 0.65 16,51 6 2 0.72 18,29 0.95 24,13 5 3 4 0.475 12,07 1 : 1 : 1 0.19 ± 0.02 4,83 ± 0,51 0.01256 × 0.30 0,319 × 0,75 0.140 3,56 1 6 3 4 0.638 16,21 0.051 1,3 Recommended PC Board Layout Dimensions are in inches mm US +1-847-639-6400 [email protected] UK +44-1236-730595 [email protected] Taiwan +886-2-2264 3646 [email protected] China +86-21-6218 8074 [email protected] Singapore + 65-6484 8412 [email protected] Document 616 Revised 05/27/09 © Coilcraft Inc. 2013 This product may not be used in medical or high risk applications without prior Coilcraft approval. Specification subject to change without notice. Please check web site for latest information.