Document 729
For Microsemi
Flyback Transformer PoE PD Power Supply
•ꢀ Developedꢀ forꢀ useꢀ withꢀ Microsemiꢀ UC3844ꢀ Currentꢀ Modeꢀ
Controller and LX1752 Buck Regulator
•ꢀ 1500ꢀVrms,ꢀoneꢀminuteꢀisolationꢀfromꢀprimary,ꢀauxiliaryꢀandꢀ
reset to secondary;500Vrms from primary and reset to auxiliary
•ꢀ Designedꢀforꢀ36ꢀVꢀ–ꢀ57ꢀVꢀinput;ꢀ200ꢀkHz
Core material Ferrite
Terminations RoHS tin-silver over tin over nickel over phos bronze.
Other terminations available at additional cost.
Weight 6.7 g
Ambient temperature –40°C to +85°C
Storage temperature Component: –40°C to +85°C.
Tape and reel packaging: –40°C to +80°C
Resistance to soldering heat Max three 40 second reflows at
+260°C, parts cooled to room temperature between cycles
Moisture Sensitivity Level ꢁMSLH 1 (unlimited floor life at <30°C /
85% relative humidity)
Mean Time Between Failures ꢁMTBFH 26,315,789 hours
Packaging 175 per 13″ reel Plastic tape: 32 mm wide, 0.5 mm thick,
28 mm pocket spacing, 12.93 mm pocket depth
PCB washing Only pure water or alcohol recommended
Part
L at 0 A2
±±0ꢀ ꢁ(µH
L at Ipk3
min ꢁ(µH
Input
voltage ꢁVH
DCR max
ꢁOhmsH
Leakage L4
max ꢁ(µH
Turns
ratios
Ipk3
ꢁAH
number1
Outputs5
HA3905-CL_
27.0
24.3
37 –57
0.170 (pri)
1.9
3.75:1 (pri:sec )
1.36:1 (pri:aux)
1:1 (pri:reset)
1.2
5 V, 2.5 A (sec)
12 V, 20 mA (aux)
0.015 (sec)
0.385 (aux)
0.371 (reset)
1. When ordering, please specify packaging code:
µA3905-CLD
2. Inductance is for the primary, measured at 250 kHz, 0.1 Vrms, 0 Adc.
3. Ipk is peak primary current drawn at minimum input voltage.
4. Leakage inductance measured on the primary winding with all second-
ary pins shorted.
5. Output of the seconday is with the windings connected in parallel.
6. Electrical specifications at 25°C.
Packaging: D = 13″ machine-ready reel. 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.
Refer to Doc 362 “Soldering Surface Mount Components” before soldering.
Dot above pin1
5
10
9
Pri
Sec
0.500
12,70
max
3
6
7
Reset
4
0.004/0,10
0.039
1,00
1
0.699
17,75
max
Aux
0.050
1,27
0.028
0,70
0.512
13,00
2
0.080
2,03
0.590
14,99
6
Secondary windings to be connected
in parallel on the PC board
5
1
0.530
13,46
Recommended
Land Pattern
max
1
0.098
2,50
0.098
2,50
10
inches
mm
Dimensions are in
Document 729 Revised 08/13/09
US +1-847-639-6400 sales@coilcraft.com
UK +44-1236-730595 sales@coilcraft-europe.com
Taiwan +886-2-2264 3646 sales@coilcraft.com.tw
China +86-21-6218 8074 sales@coilcraft.com.cn
Singapore + 65-6484 8412 sales@coilcraft.com.sg
© Coilcraft Inc. 2012
This product may not be used in medical of high
risk applications without prior Coilcraft approval.
Specification subject to change without notice.
Please check out web site for latest information.