Document 704-1
Coupled Inductors
MSD1278T
For high temperature
applications
The MSD1278T series of shielded coupled inductors was
designed specifically for high temperature applications –
up to 125°C ambient.
Tight coupling (k
≥
0.98) and 500 V isolation make them
ideal for use in a variety of circuits including flyback, multi-
output buck, SEPIC and Zeta. These parts provide high
inductance, high efficiency and excellent current handling.
They can also be used as two single inductors connected
in series or parallel or as a common mode choke.
+
D
+
L1
V
IN
C
SW
L2
C
V
OUT
–
–
Typical Flyback Converter
+
C
V
OUT
AUX
0.484
max
12,3
Dot indicates pin1
Dash number
Internal code
L2
+
V
IN
SW
D
D
–
+
0.484
max
12,3
123
X
L1
C
V
OUT
–
–
Typical Buck Converter with auxiliary output
0.308 ±0.010
*
7,8 ±0,25
+
Recommended
Land Pattern
0.217
5,5
D
+
C
V
OUT
L1
V
IN
C1
Q
C
L2
0.197
5,0
0.138
3,5
0.197
5,0
3
2
4
1
0.157
4,0
2
3
–
Typical SEPIC schematic
–
0.177
4,5
4
1
+
Q
C1
+
L2
D
C
V
OUT
0.059
1,5
0.079
2,0
V
IN
C
L1
*
For optional tin-lead and tin-silver-copper
terminations, dimensions are for the mounted
part. Dimensions before mounting can be
an additional 0.012 inch (0,3 mm).
–
1
L1
3
2
L2
4
Typical Zeta schematic
–
Dimensions are in
inches
mm
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 704-1
Revised 04/05/13
© 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.
Document 704-2
High Temperature Coupled Inductors – MSD1278T
Part number
1
MSD1278T-472ML_
MSD1278T-562ML_
MSD1278T-682ML_
MSD1278T-822ML_
MSD1278T-103ML_
MSD1278T-123ML_
MSD1278T-153ML_
MSD1278T-183ML_
MSD1278T-223ML_
MSD1278T-273ML_
MSD1278T-333ML_
MSD1278T-393ML_
MSD1278T-473ML_
MSD1278T-563ML_
MSD1278T-683ML_
MSD1278T-823ML_
MSD1278T-104ML_
MSD1278T-124KL_
MSD1278T-154KL_
MSD1278T-184KL_
MSD1278T-224KL_
MSD1278T-274KL_
MSD1278T-334KL_
MSD1278T-394KL_
MSD1278T-474KL_
MSD1278T-564KL_
MSD1278T-684KL_
MSD1278T-824KL_
MSD1278T-105KL_
Inductance
2
(µH)
4.7 ±20%
5.6 ±20%
6.8 ±20%
8.2 ±20%
10 ±20%
12 ±20%
15 ±20%
18 ±20%
22 ±20%
27 ±20%
33 ±20%
39 ±20%
47 ±20%
56 ±20%
68 ±20%
82 ±20%
100 ±20%
120 ±10%
150 ±10%
180 ±10%
220 ±10%
270 ±10%
330 ±10%
390 ±10%
470 ±10%
560 ±10%
680 ±10%
820 ±10%
1000 ±10%
DCR
max
3
(Ohms)
0.040
0.046
0.048
0.055
0.058
0.062
0.072
0.080
0.096
0.120
0.150
0.161
0.180
0.190
0.210
0.280
0.300
0.410
0.460
0.510
0.690
0.900
1.02
1.12
1.53
1.69
2.29
2.55
2.87
SRF
typ
4
(MHz)
33.0
30.0
23.0
20.0
17.0
15.0
13.0
12.0
11.0
10.0
9.5
8.5
7.5
7.0
6.5
5.0
4.5
4.3
4.1
4.0
3.4
3.1
2.9
2.7
2.2
2.0
1.7
1.4
1.3
Coupling Leakage
coefficient
L typ
5
typ
(µH)
0.98
0.98
0.98
0.98
0.98
0.98
0.99
0.99
0.99
0.99
0.99
0.99
0.99
0.99
0.99
0.99
>0.99
0.99
>0.99
>0.99
>0.99
>0.99
0.99
>0.99
>0.99
>0.99
>0.99
>0.99
>0.99
0.22
0.23
0.22
0.34
0.34
0.36
0.41
0.37
0.41
0.43
0.56
0.64
0.70
0.76
0.88
0.85
0.90
1.31
1.46
0.93
1.54
1.17
4.14
1.64
0.25
2.68
2.11
2.39
4.28
Isat
(A)
6
10%
20% 30%
drop drop drop
13.90
13.38
12.10
10.30
8.80
8.20
7.40
6.50
6.00
5.80
5.50
4.70
3.70
3.60
3.50
3.30
2.80
2.60
2.20
2.10
1.90
1.70
1.50
1.40
1.30
1.20
1.00
0.900
0.850
15.20
14.86
13.56
11.52
10.00
9.18
8.36
7.38
6.80
6.56
6.10
5.26
4.34
4.18
4.04
3.72
3.24
2.94
2.54
2.42
2.16
1.94
1.70
1.60
1.50
1.34
1.08
1.04
0.948
16.36
15.74
14.20
12.20
10.66
9.74
9.03
7.86
7.26
7.02
6.52
5.60
4.60
4.50
4.32
4.02
3.46
3.16
2.70
2.58
2.28
2.10
1.84
1.70
1.60
1.46
1.22
1.18
1.05
Irms
(A)
both
one
windings
7
winding
8
3.16
2.87
2.81
2.76
2.56
2.48
2.30
2.18
1.99
1.78
1.59
1.54
1.45
1.41
1.35
1.16
1.13
0.96
0.91
0.86
0.74
0.65
0.61
0.58
0.50
0.47
0.41
0.39
0.37
4.47
4.06
3.98
3.90
3.62
3.50
3.25
3.08
2.81
2.52
2.25
2.18
2.05
2.00
1.90
1.65
1.59
1.36
1.29
1.22
1.05
0.92
0.86
0.82
0.70
0.67
0.58
0.55
0.52
1. When ordering, please specify
termination
and
packaging
code:
MSD1278T-105KLD
Termination: L
= RoHS compliant matte tin over nickel over phos
bronze
Special order:
T
= RoHS tin-silver-copper
(95.5/4/0.5) or
S
= non-RoHS tin-lead (63/37).
Packaging: D
= 13″ machine-ready reel. EIA-481 embossed plastic
tape (500 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 shown for each winding, measured at 100 kHz, 0.1 Vrms,
0 Adc on an Agilent/HP 4284A LCR meter or equivalent. When leads
are connected in parallel, inductance is the same value. When leads are
connected in series, inductance is four times the value.
3. DCR is for each winding. When leads are connected in parallel, DCR
is half the value. When leads are connected in series, DCR is twice the
value.
4. SRF measured using an Agilent/HP 4191A or equivalent. When leads
are connected in parallel, SRF is the same value.
5. Leakage inductance is for L1 and is measured with L2 shorted.
6. DC current, at which the inductance drops the specified amount from its
value without current. It is the sum of the current flowing in both windings.
7. Equal current when applied to each winding simultaneously that causes
a 40°C temperature rise from 25°C ambient. See temperature rise
calculation.
8. Maximum current when applied to one winding that causes a 40°C
temperature rise from 25°C ambient. See temperature rise calculation.
9. Electrical specifications at 25°C.
Refer to Doc 639 “Selecting Coupled Inductors for SEPIC Applications.”
Refer to Doc 362 “Soldering Surface Mount Components” before soldering.
Coupled Inductor Core and Winding Loss Calculator
This web-based utility allows you to enter frequency, peak-to-peak
(ripple) current, and
Irms
current to predict temperature rise and overall
losses, including core loss.
Go to online calculator
.
Core material
Ferrite
Core and winding loss
Go to online calculator
Terminations
RoHS compliant matte tin over nickel over phos
bronze. Other terminations available at additional cost.
Weight:
3.7 – 4.4 g
Ambient temperature
–40°C to +125°C with
Irms
current, +125°C to
+165°C with derated current
Storage temperature
Component: –40°C to +165°C.
Tape and reel packaging: –40°C to +80°C
Winding-to-winding and winding-to-core isolation
500 Vrms
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) / Mean Time Between Failures (MTBF)
38 per billion hours / 26,315,789 hours, calculated per Telcordia SR-332
Packaging
500/13″ reel; Plastic tape: 24 mm wide, 0.5 mm thick,
16 mm pocket spacing, 8.7 mm pocket depth
PCB washing
Tested with pure water or alcohol only. For other solvents,
see
Doc787_PCB_Washing.pdf.
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 704-2
Revised 04/05/13
© 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.
Document 704-3
High Temperature Coupled Inductors – MSD1278T
Typical L vs Current
10000
Typical L vs Frequency
10000
1000
1000 µH
470 µH
1000
1000 µH
470 µH
Inductance (µH)
100
100 µH
47 µH
Inductance (µH)
100
100 µH
47 µH
10 µH
4.7 µH
10
10 µH
4.7 µH
10
1
0.1
1
10
100
1
Current (A)
0.01
0.1
1
10
Frequency (MHz)
Current Derating
120
110
100
90
80
70
60
50
40
30
20
10
0
-40 -20
Percent of rated Current
Isat
Irms
0
20
40
60
80
100
120
140
160 180
Ambient temperature (°C)
25°C
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 704-3
Revised 04/05/13
© 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.