English
Language : 

D1766_13 Datasheet, PDF (1/1 Pages) Coilcraft lnc. – Flyback Transformer
Document 529
Flyback Transformer For Linear Technology
LTC4267 PoE PD Interface
The D1766-AL multiple-output transformer was developed
for use with Linear Technology LTC4267 Power over Eth-
ernet IEEE 802.3af PD Interface with Integrated Switching
Regulator. It is ideal for use in telecommunications isolated
converters and isolated power supplies.
This low-profile transformer is designed for an input volt-
age of 36 – 72 Volts. It features interleaved primary and
secondary windings to minimize leakage inductance and
1500 Vrms isolation between windings.
Coilcraft can also custom engineer a transformer to meet
your specific requirements. For free evaluation samples,
contact Coilcraft or visit www.coilcraft.com.
Part
  number1
Inductance
  at 0 Adc2
±10% (µH)
Inductance
  at Ipk3
DCR max
min (µH)
(Ohms)
Leakage
  Inductance4
Turns ratio
  Ipk3
max (µH) pri : S1  pri : S2,S3 (A)
D1766-AL_
221
200
0.420 (pins 1 – 3)
5.1
9.6 : 1
24 : 1
1.5
0.013 (pins 8 – 5)
0.013 (pins 7 – 6)
0.015 (pins 10 – 9)
0.030 (pins 12 – 11)
  Outputs5
3.3 V, 0.5 A (S3)
2.5 V, 1.5 A (S2)
1.8 V, 2.5 A (S1)
1. When ordering, please specify packaging code:
Packaging:
D1766-ALD
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.
2. Inductance is for the primary, measured at 200 kHz, 1.1 Vrms, 0 Adc.
3. Peak primary current drawn at minimum input voltage.
4. Leakage inductance is for the primary and is measured with secondary
windings shorted.
5. All outputs are referenced to ground.
6. Operating temperature range –40°C to +125°C.
7. Electrical specifications at 25°C.
Refer to Doc 362 “Soldering Surface Mount Components” before soldering.
Dot indicates pin 1
1
0.810 max
20,57
6
12
D1766-AL
XXXXY
7
1.181
30,00
max
Parts manufactured prior
to December 2011 may
be marked differently.
0.450
11,43
max
0.084
2,13
0.969
24,6
0.004 /0,10
1
12 3.3 V
Pri
S3
3
11
10 2.5 V
S2
9
8,7 1.8 V
S1
5,6 GND
The secondary windings are to
be connected in series on the
board by connecting pins 9, 8
and 7 together and pins 11 and
10 together. Outputs at pins 12,
11,10 and 8,7 are referenced
to ground (pins 5,6).
0.028
0,72 6
0.827
21,0
0.130
3,30
7
1
0.930
23,62
0.050
1,27
Core material Ferrite
Terminations  RoHS tin-silver (96.5/3.5) over tin over
nickel over phos bronze. Other terminations available
at additional cost.
Weight  12.7 g
Ambient temperature  –40°C to +125°C
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)
Failures in Time (FIT)  38 per billion hours
Mean Time Between Failures (MTBF)
26,315,789 hours, calculated per Telcordia SR-332
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 with pure water or alcohol only.
For other solvents, see Doc787_PCB_Washing.pdf.
0.118 1
3,0
Recommended
Land Pattern
12
Dimensions are
in
inches
mm
0.118
3,0
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 529  Revised 12/22/11
© Coilcraft Inc. 2013
This product may not be used in medical or high
risk applications without prior Coilcraft approval.
Specification subject to change without notice.
Please check web site for latest information.