Document 544
For ST Microelectronics
PoE Transformers STE12PS PSE Power Controller
These surface mount flyback transformers were devel-
oped specifically for the ST Microelectronics STE12PS
12-Channel PSE Power Control Device.
They are designed to work with a 3.3 V input to provide
a 12 V output. Isolation is 500 Vdc from each primary
winding to the secondary winding.
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.
DCR max (Ohms)
Part
L at 0 A2
±±0ꢀ (ꢁµ)
L at Ipk3
min (ꢁµ)
Leakage L
max (ꢁµ)4
Turns ratio5
pri :sec
Ipk3
(A)
number1
±-5
2-6
±2-7
Output
DA2420-AL_
DA2421-AL_
330
330
297
297
0.756 0.886
0.803 0.984 14.145
5.920
6.00
4.83
1: 2
1: 3
2.0
2.0
12 V, 100 mA
12 V, 100 mA
1. When ordering, please specify a packaging code:
DA2420-ALD
2. Inductance is for the primary, measured at 100 kHz, 0.1 Vrms, 0 Adc.
3. Ipk is the peak current drawn at minimum input voltage.
4. Leakage inductance measured on the primary windings with all
secondary pins shorted.
Packaging: D = 13″ machine ready reel. EIA-481 embossed plastic
tape (175 per full reel).
5. Turns ratio is with the primary windings connected in parallel.
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.
6. Operating temperature range
7. Electrical specifications at 25°C.
–40°C to +125°C.
1
2
Dot indicates pin 1
1
0.130
3,30
0.930
23,62
0.028
0,711
0.050
1,27
12
Sec
12
1
Pri
0.810
20,57
Recommended
Land Pattern
6
5
7
max
DA242X-AL
Primary windings to be
connected in parallel on
the PC board.
6
7
0.118
3,0
0.118
3,0
1.181
max
30,00
0.450
11,43
max
0.004/0,10
0.827
21,00
0.080
2,03
Weight:
14.1 – 14.6 g
0.969
24,60
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.
Document544 Revised09/11/06
© Coilcraft, Inc. 2008