IMX4 Series Data Sheet
4 Watt DC-DC Converters
Features
•
RoHS lead-free-solder and lead-solder-exempted
products are available.
•
Input voltage ranges up to 121 VDC
•
Voltage withstand test 1500 VAC
•
1 or 2 isolated outputs up to 48 V
20
0.8"
32
1.25"
8.5
0.34"
•
Extremely wide input voltage ranges
•
Immunity according to IEC/EN 61000-4-2, -3, -4, -5, -6
•
High efficiency (typ. 83%)
• Flexible load distribution on outputs
•
Outputs no-load, overload, and short-circuit proof
•
High reliability
•
Operating ambient temperature – 40 to +85 °C
•
Thermal protection
•
Industrial and alternative pinout
•
DIL 24 case with 8.5 mm profile
Safety-approved to IEC 60950-1 2
nd
Ed and CSA/UL
60950-1 2
nd
Ed.
2
2
70IMX4
models
Description
The IMX4 Series of board-mountable 4-watt DC-DC converters
has been designed according to the latest industry
requirements and standards. The converters are particularly
suitable for use in mobile or stationary applications in trans-
port, industry, or telecom, where variable input voltages or high
transient voltages are prevalent.
Covering a total input voltage range from 8.4 VDC up to
121 VDC with three different models, the converters are
available with single or dual output from 3.3 up to ±24 VDC
with flexible load distribution. Features include efficient input
and output filtering with unsurpassed transient and surge
protection, low output ripple and noise, consistently high
efficiency over the entire input voltage range and high
reliability as well as excellent dynamic response to load and
line changes.
The converters exhibit basic insulation and are designed and
built according to the international safety standards IEC/EN
60950-1 2
nd
Ed. 70IMX4 models are CE-marked.
A special feature is their small case size, DIL 24 with only
8.5 mm profile. The circuit is comprised of integrated planar
magnetics, and all components are automatically assembled
and solidly soldered onto a single PCB without any wire
connection. Thanks to the rigid mechanical design, the
converters withstand an extremely high level of shock and
vibrations. Careful consideration of possible thermal stresses
ensure the absence of hot spots providing long life in
environments where temperature cycles are a reality. The
thermal design allows operation at full load up to an ambient
temperature of 85 °C in free air without using any potting
material.
Several options, such as open-frame or an alternative industrial
pinout, provide a high level of application-specific engineering
and design-in flexibility.
Table of Contents
Page
Page
Electromagnetic Compatibility (EMC) .................................... 8
Mechanical Data .................................................................... 9
Immunity to Environmental Conditions ................................ 10
Safety and Installation Instructions ...................................... 10
Description of Options ......................................................... 11
Description ............................................................................. 1
Model Selection ..................................................................... 2
Functional Description ........................................................... 3
Electrical Input Data ............................................................... 4
Electrical Output Data ............................................................ 6
Copyright © 2015, Bel Power Solutions Inc. All rights reserved.
MELCHER
BCD20006-G Rev AE, 16-Sep-2015
The Power Partners.
Page 1 of 12
IMX4 Series Data Sheet
4 Watt DC-DC Converters
Model Selection
Table 1: Model Selection
Output 1
V
o1 nom
I
o1 nom
[ VDC] [mA]
1
3.3
3.3
5
5
5
5
12
12
12
12
15
15
15
15
+5
+5
+5
+12
+12
+15
+15
+24
+24
1
Output 2
V
o2 nom
I
o2 nom
[ VDC]
[mA]
1
-
-
-
-
-
-
-
-
-
-
-
-
-
-
–5
–5
–5
–12
–12
–15
–15
–24
–24
-
-
-
-
-
-
-
-
-
-
-
-
-
-
350
350
350
170
170
140
140
80
80
Output power
P
o nom
[W ]
3.0
3.0
3.5
3.5
3.5
3.5
3.6
4.1
4.1
4.1
3.75
4.2
4.2
4.2
3.5
3.5
3.5
4.1
4.1
4.2
4.2
3.8
3.8
Input voltage
range
[ VDC]
8.4 to 36
16.8 to 75
4.7 to 16.8
8.4 to 36
16.8 to 75
40 to 121
4.7 to 16.8
8.4 to 36
16.8 to 75
40 to 121
4.7 to 16.8
8.4 to 36
16.8 to 75
40 to 121
8.4 to 36
16.8 to 75
40 to 121
8.4 to 36
16.8 to 75
8.4 to 36
16.8 to 75
8.4 to 36
16.8 to 75
Efficiency
η
min
η
typ
[%]
[%]
76
76
76
78
78
77
79
78
78
77
79
78
78.7
79
77
76
75.5
76
76
78
76
76
76
77.5
78
-
81
81
78
-
82
82
82
-
82
82
80.5
81
81
78
82
82
82
82
83
83
Model
Options
900
900
700
700
700
700
300
340
340
340
250
280
280
280
350
350
350
170
170
140
140
80
80
20IMX4-03-8
40IMX4-03-8
5IMX4-05-8
20IMX4-05-8
40IMX4-05-8
70IMX4-05-8
5IMX4-12-8
20IMX4-12-8
40IMX4-12-8
70IMX4-12-8
5IMX4-15-8
20IMX4-15-8
40IMX4-15-8
70IMX4-15-8
20IMX4-0505-8
40IMX4-0505-8
70IMX4-0505-8
20IMX4-1212-8
40IMX4-1212-8
20IMX4-1515-8
40IMX4-1515-8
20IMX4-2424-8
40IMX4-2424-8
Z, G
Z, G
Z, G
K, Z, G
K, Z, G
G
Z, G
K, Z, G
K, Z, G
G
Z, G
K, Z, G
K, Z, G
G
K, Z, G
K, Z, G
G
K, Z, G
K, Z, G
K, Z, G
K, Z, G
Z, G
Z, G
Flexible load distribution on double-outputs is possible.
Preferred for new designs.
Part Number Description
Input voltage range
V
i
4.7 to 16.8 VDC ........................................... 5
8.4 to 36 VDC ............................................ 20
16.8 to 75 VDC .......................................... 40
40 to 121 VDC ........................................... 70
Series ......................................................................... IMX4
Output voltage of output 1 ...................... 03, 05, 12, 15, 24
Output voltage of output 2 ............................ 05, 12, 15, 24
Operating ambient temperature range –40 to 85 °C ...... -8
Options:
Alternative pinout ......................................... K
Open frame .................................................. Z
RoHS compliant for all six substances ......... G
20 IMX4 - 05 05 -8 K Z G
Note:
The sequence of options must follow the order above. This part number description is descriptive only; it is not inteded for
creating part numbers.
Example:
40IMX4-0505-8KG: DC-DC converter, input voltage range 16.8 to 75 V, 2 outputs providing ± 5 V, 350 mA,
temperature range – 40 to 85 °C, alternative pinout, RoHS-compliant for all si x substances
MELCHER
BCD20006-G Rev AE, 16-Sep-2015
The Power Partners.
Page 2 of 12
IMX4 Series Data Sheet
4 Watt DC-DC Converters
Functional Description
The IMX4 Series converters are feedback-controlled flyback
converters using current mode PWM (Pulse Width
Modulation). The input is protected against transients by
means of a suppressor diode.
The output voltage is monitored by a separate transformer
winding close to the secondary windings and fed back to the
control circuit.
Vi–
24
Vi+
1
n.c.
2
PWM
03046
13
Vo+
12
Vo–
Current limitation is provided by the primary circuit, thus
limiting the total output current (I
o nom
for single- and the sum
I
o1 nom
+
I
o2 nom
for dual-output models).
The close magnetic coupling provided by the planar
construction ensures very good regulation and allows for
flexible load distribution on dual-output models.
03044
Fig. 3
Block diagram for single-output models with alternative
pinout (option K).
Vi+
22
23
14
Vo+
03047
Vi+
1
15
Vo+
PWM
PWM
16
Vo–
2
10
11
Go
Vi–
3
10
Vi–
24
13
Vo–
Fig. 1
Block diagram for single-output models with standard
pinout.
Fig. 4
Block diagram for dual-output models with alternative
pinout (option K).
03045
Vi+
22
23
14
Vo+
PWM
16
Go
2
Vi–
3
11
Vo–
Fig. 2
Block diagram for dual-output models with standard
pinout.
MELCHER
BCD20006-G Rev AE, 16-Sep-2015
The Power Partners.
Page 3 of 12
IMX4 Series Data Sheet
4 Watt DC-DC Converters
Electrical Input Data
General conditions:
T
A
= 25 °C, unless
T
C
is specified.
Table 2: Input Data
Input
Characteristics
V
i
V
i nom
V
i sur
Input voltage range
Nominal input voltage
Conditions
T
C min
to
T
C max
I
o
= 0 to
I
o nom
min
4.7
5I MX4
20IMX4
40IMX4
70IMX4
Unit
typ max min typ max min typ max min typ max
5.0 16.8 8.4
5.0
--
0.25 0.5
--
--
--
--
20
40
0.25 0.5
5
12
15
0.54
3.7
400
100
A
A
20
36 16.8
2
40
100
0.25 0.5
5
12
5
0.3
4.2
400
60
A
10
0.3
5
12
5
0.15
5.6
400
30
10
mA
µF
A
kHz
mA
pp
Class
75
40
70
150
0.6
s
ms
121
VDC
Repetitive surge voltage abs. max input (3 s)
t
start-up
Converter start-up time
1
Worst case condition at
V
i min
and full load
t
rise
Rise time
1
V
i nom
I
o nom
resistive load
capacitive load
I
i o
C
i
I
inr p
f
s
I
i rr
v
i RFI
1
2
3
4
No-load input current
Input capacitance
Inrush peak current
Switching frequency
I
o
= 0,
V
i min
to
V
i max
V
i
=
V
i nom 3
V
i min
to
V
i max
,
I
o
= 0 to
I
o nom
EN 55011/55022
4
3.8
400
--
--
Reflected ripple current
I
o
= 0 to
I
o nom
Input RFI level
conducted
Measured with a resistive or max. admissible capacitive load; see fig. 5
Operation at lower input voltage possible:
P
o
approx. 80% of
P
o nom
at
V
i min
= 14.4 V
Source impedance according to ETS 300132-2, version 4.3.
External capacitors required according to table 3.
Start-up
V
o
Filter to Comply with EN 55011/55022
t
rise
04008b
V
o nom
Electromagnetic emission requirements according to table
Electrical Input Data
can be achieved by adding an external
capacitor as close as possible to the input terminals (see fig. 7
and table 3).
t
Vi+
+
C
i
Vi–
04035b
Fig. 5
t
startup
Converter start-up and rise time
Inrush Current
The inrush current has been kept as low as possible by
choosing a very small input capacitance. A series resistor may
be inserted in the input line to further limit this current.
A
3
2
1
0
0
10
20
30
40
µs
04034a
Fig. 7
Input capacitors
Table 3: Input electrolytic capacitors
Model
C
i
20IMX4
100
µF
50 V
40IMX4
47
µF
100 V
70IMX4
330
µF
200 V
Fig. 6
Typ. inrush current at V
i nom
, P
o nom
versus time measured
according to ETS 300132-2, version 4.3 (40IMX4).
MELCHER
BCD20006-G Rev AE, 16-Sep-2015
The Power Partners.
Page 4 of 12
IMX4 Series Data Sheet
4 Watt DC-DC Converters
Input Transient Voltage Protection
In many applications transient voltages on the converter input
are always possible. These may be caused for example by
short circuits between Vi+ and Vi–, where the network
inductance may generate high energy pulses.
In order to protect the converter, a transient voltage sup-
pressor diode is fitted at the input; see table below.
Table 4: Built-in transient voltage suppressor
Model
Breakdown
voltage
V
BR nom
--
40 V
100 V
150 V
Peak power
at 1 ms
P
P
--
600 W
600 W
600 W
Peak pulse
current
I
PP
--
10.3 A
4.1 A
2.9 A
Fuse and Reverse Polarity Protection
The suppressor diode on the input also protects against
reverse polarity input voltage. An external fast fuse is required
to limit this reverse current; see table below.
Table 6: External input fuse
Model
5IMX4
20IMX4
40IMX4
70IMX4
Fuse type
Fast 1.6 A
Fast 1 A
Fast 0.5 A
Fast 0.315 A
5IMX4
20IMX4
40IMX4
70IMX4
If transients generating currents above the peak pulse current
I
PP
are possible, an external limiting network such as the circuit
shown in figure 8 is recommended. It provides compliance with
transients according to IEC/EN 61000-4-5, level 2. The comp
onents are specified in table 5.
If 40IMX4 converters should withstand 150 V transients
according to 19Pfl1, the same external circuitry with similar
components as shown in figure 8 can be used.
L
i
Vi+
C
i
+
D
Vi–
04036b
Fig. 8
External circuitry to comply with
IEC/EN 61000-4-5, level 2.
Table 5: Components for the circuitry fig. 8
Model
L
i
C
i
D
20IMX4
330 µH, 0.42 W
1A
68 µF, 50 V
ON 1.5KE 39 A
40IMX4
330 µH, 0.42 W
0.6 A
68 µF, 100 V
ON 1.5KE 82 A
70IMX4
330 µH, 0.65 W
0.3 A
100 µF, 200 V
–
MELCHER
BCD20006-G Rev AE, 16-Sep-2015
The Power Partners.
Page 5 of 12
