Document 621-1
Coupled Inductors – MSD7342
For Flyback, SEPIC
and other Applications
• Tight coupling (k
≥
0.97) and 200 V isolation make the MSD7342
series of coupled inductors ideal for use in a variety of circuits
including flyback, multi-output buck and SEPIC.
• They provide high inductance, high efficiency and excellent
current handling in a rugged, low cost part.
• Can also be used as two single inductors connected in series
or parallel, as a common mode choke or as a 1 : 1 transformer.
+
D
+
L1
V
IN
C
SW
L2
C
V
OUT
–
–
Typical Flyback Converter
L2
D
+
C
V
OUT
AUX
–
+
0.295
max
7,5
V
IN
SW
D
+
L1
C
V
OUT
Dot indicates
pin 1
–
–
Typical Buck Converter with auxiliary output
1
L1
3
2
L2
4
V
IN
0.295
max
7,5
123
+
L1
Q
C1
D
+
C
V
OUT
L2
0.181
max
4,6
0.028
0,7
0.091
2,3
3
2
4
1
–
Typical SEPIC schematic
–
Recommended
Land Pattern
0.110
2,8
0.083
2,1
2
1
0.150
3,8
0.063
1,6
If board traces
are run in these
areas, consider
masking them to
prevent shorting.
3
4
0.130
3,3
0.043
1,10
Dimensions are in
inches
mm
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
0.76 – 0.87g
Ambient temperature
–40°C to +85°C with
Irms
current, +85°C to
+125°C with derated current
Storage temperature
Component: –40°C to +125°C.
Tape and reel packaging: –40°C to +80°C
Winding to winding isolation
200 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
250/7″ reel; 1000/13″ reel Plastic tape: 16 mm wide,
0.4 mm thick, 12 mm pocket spacing, 4.9 mm pocket depth
PCB washing
Tested with pure water or alcohol only. For other solvents,
see Doc787_PCB_Washing.pdf.
Document 621-1
Revised 11/07/13
Specifications subject to change without notice.
US
+1-847-639-6400 sales@coilcraft.com
Please check
sales@coilcraft-europe.com
UK
+44-1236-730595
our website for latest information.
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. 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 621-2
Coupled Inductors – MSD7342 Series
Part number
1
MSD7342-252ML_
MSD7342-332ML_
MSD7342-472ML_
MSD7342-562ML_
MSD7342-682ML_
MSD7342-822ML_
MSD7342-103ML_
MSD7342-123ML_
MSD7342-153ML_
MSD7342-183ML_
MSD7342-223ML_
MSD7342-273ML_
MSD7342-333ML_
MSD7342-393ML_
MSD7342-473ML_
MSD7342-563ML_
MSD7342-683ML_
MSD7342-823ML_
MSD7342-104ML_
MSD7342-124ML_
MSD7342-154ML_
MSD7342-184ML_
MSD7342-224ML_
MSD7342-274ML_
MSD7342-334ML_
MSD7342-394ML_
MSD7342-474ML_
MSD7342-564ML_
MSD7342-684ML_
MSD7342-824ML_
MSD7342-105ML_
Inductance
2
DCR max
3
SRF typ
4
±20% (µH)
(Ohms)
(MHz)
2.5
3.3
4.7
5.6
6.8
8.2
10
12
15
18
22
27
33
39
47
56
68
82
100
120
150
180
220
270
330
390
470
560
680
820
1000
0.033
0.037
0.051
0.063
0.070
0.075
0.100
0.120
0.130
0.170
0.220
0.250
0.270
0.380
0.420
0.460
0.600
0.680
0.770
1.03
1.35
1.52
1.72
2.41
2.70
3.05
4.00
4.43
5.00
6.80
7.80
55
43
35
32
30
27
22
20
18
15
13.5
12.0
11.0
10.0
9.5
8.7
7.3
6.2
5.5
4.5
4.0
3.8
3.5
3.3
3.0
2.8
2.6
2.5
2.3
2.2
2.0
Coupling Leakage
coefficient
L typ
5
typ
(µH)
0.97
0.99
0.99
0.99
0.99
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
0.14
0.09
0.11
0.09
0.14
0.25
0.30
0.36
0.49
0.16
0.20
0.20
0.15
0.70
0.30
0.51
0.51
1.17
0.96
0.61
0.54
0.75
1.43
1.56
1.65
4.73
5.50
4.85
7.59
8.01
8.69
10%
drop
6.0
5.2
4.1
3.9
3.7
3.3
2.8
2.5
2.2
2.0
1.9
1.7
1.5
1.3
1.2
1.1
1.0
0.90
0.80
0.70
0.65
0.62
0.59
0.55
0.49
0.45
0.41
0.38
0.36
0.30
0.27
Isat
(A)
6
20%
30%
drop
drop
6.2
5.3
4.3
4.1
3.8
3.4
2.9
2.6
2.3
2.2
2.0
1.8
1.6
1.4
1.3
1.2
1.1
1.00
0.92
0.80
0.76
0.66
0.62
0.57
0.52
0.47
0.43
0.40
0.37
0.32
0.29
6.3
5.4
4.6
4.2
3.9
3.5
3.0
2.7
2.4
2.3
2.1
1.9
1.7
1.5
1.4
1.3
1.2
1.1
0.98
0.90
0.80
0.73
0.66
0.60
0.54
0.50
0.46
0.42
0.38
0.35
0.31
Irms
(A)
both
one
windings
7
winding
8
2.17
2.05
1.74
1.57
1.49
1.44
1.24
1.14
1.09
0.95
0.84
0.79
0.76
0.64
0.61
0.58
0.51
0.48
0.45
0.39
0.34
0.32
0.30
0.25
0.24
0.23
0.20
0.19
0.18
0.15
0.14
3.06
2.89
2.46
2.22
2.10
2.03
1.76
1.61
1.54
1.35
1.19
1.11
1.07
0.90
0.86
0.82
0.72
0.67
0.63
0.55
0.48
0.45
0.42
0.36
0.34
0.32
0.28
0.26
0.25
0.21
0.20
1. When ordering, please specify
termination
and
packaging
codes:
MSD7342-105MLC
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: C
= 7″ machine-ready reel. EIA-481 embossed plastic
tape (250 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 C instead.
D
= 13″ machine-ready reel. EIA-481 embossed plastic
tape. Factory order only, not stocked (1000 parts per
full reel).
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
Specifications subject to change without notice.
US
+1-847-639-6400 sales@coilcraft.com
Please check
sales@coilcraft-europe.com
UK
+44-1236-730595
our website for latest information.
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 621-2
Document 621-2
Revised 11/07/13
Revised 02/23/11
© 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.
Document 621-3
Coupled Inductors – MSD7342 Series
Typical L vs Current
10000
1000 µH
470 µH
Typical L vs Frequency
10000
1000 µH
470 µH
1000
1000
Inductance (µH)
100
100 µH
47 µH
Inductance (µH)
100
100 µH
47 µH
10
10 µH
4.7 µH
10
10 µH
4.7 µH
1
0.01
0.1
1
10
1
0.1
1
10
100
Current (A)
Frequency (MHz)
Irms Derating
120
110
100
Percent of rated
I
rms
90
80
70
60
50
40
30
20
10
0
-40
-20
0
20
40
60
80
100
120 140
Ambient temperature (°C)
25°C
Specifications subject to change without notice.
US
+1-847-639-6400 sales@coilcraft.com
Please check
sales@coilcraft-europe.com
UK
+44-1236-730595
our website for latest information.
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 621-3
Document 621-3
Revised 11/07/13
Revised 02/23/11
© 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.