Coilcraft DA2420-AL and DA2421-AL PoE Transformers for ST Micro STE12PS
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SMT Flyback Transformers
for ST Micro STE12PS

  • Developed for ST Microelectronics STE12PS 12-Channel PSE Power Controller
  • 3.3 V input; 12 V output
  • 500 Vdc isolation from primary to secondary
  • RoHS-compliant. 260°C compatible. Tin-silver over tin over nickel over phos bronze terminations


Part number1
Click to get parts
L at 0 A2
±10% (µH)
L at Ipk3
min (µH)
DCR max (Ohms)4 Leakage
L max5
1-5 2-6 12-7
DA2420-AL_ 330 297 0.756 0.886 5.920 6.00 1 : 2 2.0 12 V, 100 mA
DA2421-AL_ 330 297 0.803 0.984 14.145 4.83 1 : 3 2.0 12 V, 100 mA
1 When ordering, please specify packaging code: e.g. DA2420-ALD
Primary windings to be connected in parallel on the PC board.
Packaging: D = 13" reel, machine-ready 
EIA-481 embossed plastic tape (175 parts 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 100 kHz, 0.1 Vrms, 0 Adc
3 Ipk is peak primary current drawn at minimum input voltage.
4 DCR measured at 25°C. For other operating temperatures,
use this DCR at Temperature calculator.
5 Leakage inductance measured on the primary windings with secondary pins shorted.
6 Turns ratio is with the primary windings connected in parallel.
7 Ambient temperature range: −40°C to +125°C
8 Storage temperature range: Component: −40°C to +125°C
Tape and reel packaging: −40°C to +80°C
9 Resistance to soldering heat: Three reflows at >217°C for 90 seconds (+260°C ±5°C for 20 – 40 seconds), allowing parts to cool to room temperature between.
10 Electrical specifications at 25°C.
Refer to Soldering Coilcraft Components before soldering.
PCB washing: Tested to MIL-STD-202 Method 215 plus an additional aqueous wash. More info

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Updated: April 16, 2018