Document 549 PoE Transformer For National Semiconductor LM5071 & LM5072 PD Controllers The FA2519-AL surface mount flyback transformer was developed specifically for National Semiconductor LM5071 and LM5072 Powered Devices Controllers in 13 Watt Power over Ethernet (PoE) applications. It is designed to operate at 250 kHz with a PoE input voltage of 36 – 72 Volts. It can also accept a 12 V input from auxiliary sources. Output with the secondary windings connected in parallel, is 3.3 V, 3.3 A. Output of the auxiliary winding is 10 V, 20 mA. Coilcraft can also design custom transformers with voltage, inductance and DCR values to meet your specific requirements. For free evaluation samples, contact Coilcraft or order them on-line at www.coilcraft.com. Part number1 FA2519-AL_ L at 0 A2 ±10% (µH) 55 L at Ipk3 ±10% (µH) 40.2 DCR max (Ohms)4 pri aux sec 0.026 0.388 0.0026 1. When ordering, please specify a packaging code: FA2519-ALD Packaging: D = 13″ machine ready reel. EIA-481 embossed plastic tape (175 per full reel). B = Less than full reel. In tape, but not machine ready. To have a leader and trailer added ($25 charge), use code letter D instead. 2. Inductance is for the primary, measured at 250 kHz, 0.7 Vrms, 0 Adc. Dot indicates pin 1 1 12 0.028 0,711 0.130 3,30 Leakage L (µH)5 0.62 Turns ratio6 pri : sec pri : aux 1 : 0.20 1 : 0.60 0.930 23,62 1 0.050 1,27 Recommended Land Pattern FA2519-AL 6 1 2 1.181 max 30,00 4 3 5 7 0.118 3,0 0.118 3,0 Sec 9 8 7 Aux Primary windings and secondary windings to be connected in parallel on PC board. 0.827 21,00 0.969 24,60 0.004 /0,10 Weight: 13.5 g Terminations: Tin-silver over tin over nickel over phos bronze Tape and reel: 175/13″ reel, 44 mm tape width For packaging data see Tape and Reel Specifications section. Specifications subject to change without notice. Please check our website for latest information. © Coilcraft, Inc. 2008 12 11 10 6 0.450 max 11,43 0.080 2,03 Isolation7 (Vrms) 1500 3. Ipk is the peak current drawn at minimum input voltage. 4. DCR for the primary and for the secondary is with the windings connected in parallel. 5. Leakage inductance measured on the primary windings with all secondary pins shorted. 6. Turns ratio is with the primary windings and the secondary windings connected in parallel. 7. Isolation is from primary and auxiliary windings to secondary windings. 8. Operating temperature range –40°C to +125°C. 9. Electrical specifications at 25°C. Pri 0.810 max 20,57 Ipk3 (A) 2.4 Document 549 Revised 09/11/06