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DA2257-AL PoE Transformer

for TI LM5071 and LM5072

RoHS compliant
  • Developed for Texas Instruments LM5071 and LM5072 PD Controllers
  • Specified in TI  application note AN-1430
  • Designed to operate in continuous mode at 250 kHz with input voltage of 14 – 60 V
  • Can accept 12 V input from auxiliary sources.
  • Dual secondaries, separate aux and gate windings
  • Industry standard EP13 surface mount package
  • Coilcraft's DA2383-AL and FA2519-AL are also specified by TI for LM5071 and LM5072
  • The FA2677-AL is specified by TI for LM5072

Buy Now:
Count Unit price
1 $2.57
175 $2.36
700 $2.14
1400 $1.79
2800 $1.59
5000 $1.45

For high volume or non-stock items, request a quote.

. in stock, ready to ship today.
Request a Sample:

Typical Application

Works with Texas Instruments LM5071

Input Voltage Output Power Fsw
Sec1 Sec2 Gate Aux
14 V 60 V 3.3 V , 2 A 5 V , 1 A 5.5 V , 0.05 A 10 V , 0.05 A 11.6 W 250 kHz


Electrical specifications at 25°C.

Part number 1
(Hover for schematics)
at 0A (µH) 2
(Tolerance: ±10%)
min at   2.7 A (µH)
DCR max (Ω) 3 Leakage
max (µH) 4
Turns Ratio Isolation
Voltage (Vrms) 5
Pri Sec1 Sec2 Gate Aux Pri : Sec1 : Sec2 : Gate : Aux
DA2257-AL_ 35.0 30.0 0.062 0.010 0.018 0.138 0.225 0.95 1 : 0.167 : 0.278 : 0.278 : 0.5 2000
  1. When ordering, please specify packaging code: e.g. DA2257-ALD
  2. Inductance is for the primary, measured at 250 kHz, 0.2 Vrms, 0 Adc.
  3. DCR measured at 25°C. For other operating temperatures, use this DCR at Temperature calculator.
  4. Leakage inductance is for the primary winding with all other pins shorted.
  5. 2000 Vrmsisolation from primary and aux to secondaries.


  • RoHS-compliant. 260°C compatible. Tin-silver over tin over nickel over phos bronze terminations. Other terminations available at additional cost.


  • D = 13″ machine-ready reel. EIA-481 embossed plastic tape (175 parts per full reel). Quantities less than full reel available: in tape (not machine ready) or with leader and trailer ($25 charge).
  • B = Less than full reel. In an effort to simplify our part numbering system, Coilcraft is eliminating the need for multiple packaging codes. When ordering, simply change the last letter of your part number from B to D.
RoHS compliant
Ambient temperature range:
–40°C to +85°C
Storage temperature range:
Component: –40°C to +85°C.
Tape and reel packaging: –40°C to +80°C
Failures in Time (FIT) / Mean Time Between Failures (MTBF):



Physical characteristics



Tape and Reel specification


Parts per reel Reel dimensions (mm) Tape dimensions (mm) Orientation
13" (330 mm) A B C D E W P Po P1 H T da2257orientation.gif
175 330 100 13 38,4 32,4 32 28 4 2 12,93 0,5

General specification

Core Material:
175 per 13″ reel. Plastic tape: 32 mm wide, 0.5 mm thick, 28 mm pocket spacing, 12.93 mm pocket depth


Moisture Sensitivity Level (MSL):
1 (unlimited floor life at <30°C / 85% relative humidity)
Resistance to soldering heat:
Max three 40 second reflows at +260°C, parts cooled to room temperature between cycles
Refer to Soldering Coilcraft Components before soldering.
PCB Washing:
Tested with pure water or alcohol only. More Info.

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