Document 1469 -1

PoE Flyback Transformer for Si3406x• Developed for Silicon Labs Si3406, Si34601 and Si34062 30W PDFlyback converter• Designed to meet 30 W PoE IEEE 802.3at-2009 standard.
• Optimized for 220 kHz with 36 – 57 input voltage; Can also operatefrom 100 kHz to 500 kHz• Isolation: 1500 Vrms, one minute pri and aux to sec; 500 Vrms pri to aux
Core material Ferrite
Terminations RoHS tin-silver-copper over tin over nickel overphos bronze.
Weight 13.1 gAmbient temperature –40°C to +85°C
Maximum part temperature +125°C (ambient + temp rise)
Storage temperature Component: –40°C to +125°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 (MSL) 1 (unlimited floor life at <30°C /85% relative humidity)
Packaging 175 per 13″ reel Plastic tape: 44 mm wide, 0.4 mm thick,
32 mm pocket spacing, 11.9 mm pocket depth
PCB washing Tested to MIL-STD-202 Method 215 plus an additionalaqueous wash. See Doc787_PCB_Washing.pdf.		
Partnumber1
CX9642-AL_

Inductance Inductance		
DCR max (Ohms)
at 0 A2
at Ipk3±15% (µH)
min (µH)
prisecaux
70.0

60.0

0.08

0.0027

1. When ordering, please specify packaging code:
CX9642-ALD
D = 13″ machine-ready reel. EIA-481 embossed plastic
tape (175 parts per full reel). Quantities less thanfull reel available: in tape (not machine ready) or withleader and trailer ($25 charge).
2. Inductance is for the primary, measured at 333.3 kHz, 0.1 Vrms, 0 Adc.
3. Peak primary current drawn at minimum input voltage.
DCR is with the windings connected in parallel.
4. Leakage inductance is for the primary winding with the secondary windings shorted.
5. Turns ratio is with the primary and the secondary windings connected inparallel.
6. Output is with the secondary windings connected in parallel. Output of
the auxiliary winding is 14.5 V, 25 mA
7. Electrical specifications at 25°C.
Refer to Doc 362 “Soldering Surface Mount Components” before soldering.
Packaging:

0.36

Leakage		Turns ratio5
inductance4max (µH) pri : sec pri : aux
1.0

1 : 0.136 1 : 0.409

Ipk3(A)

Output63.0	  5.0 V, 6 A

12121110PriSec435987

Aux6
Connect pin 1 to 2
and pin 3 to 4 on
the PC Board.

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

Connect pin 10, 11
and 12 together
and pins 7, 8 and 9
together on the PCBoard.

Document 1469-1

Revised 07/28/21© Coilcraft Inc. 2021
This product may not be used in medical or highrisk applications without prior Coilcraft approval.
Specification subject to change without notice.
Please check web site for latest information.

Document 1469-2

Flyback Transformer for Si3406x
Dot indicates pin 1

Internal code
121

CX9642-AL

XXXXY

0.810 max
20,57
6

7

1.181
max
30,00

0.450 max
11,43
0.084
2,130.004 /0,10

0.969
24,60.827
21,0
60.028
7 0,72

0.130
3,30

0.930
23,62
10.0501,27Recommended
Land Pattern1

Dimensions are in

120.118
3,00.118
3,0inchesmm

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

Document 1469-2

Revised 07/28/21© Coilcraft Inc. 2021
This product may not be used in medical or highrisk applications without prior Coilcraft approval.
Specification subject to change without notice.
Please check web site for latest information.