ICF Series
Wide Input 1000 Watt Isolated Full Brick DC-DC
Model Number
ICF0184V1xC
ICF0442V1xC
ICF0536V1xC
ICF0621V1xC
ICF0719V1xC
Input Range
(Vdc)
Min
Max
Vout
(Vdc)
Iout
(A)
9
9
36
36
12
24
84
42
9
9
36
36
28
48
36
21
9
36
53
19
Features
4:1 Input voltage range of 9-36V
Single outputs of 12V, 24V, 28V, 48V or 53V
2250Vdc Isolation voltage (Input-to-Output)
Industry Standard full brick package
4.7" x 2.5" x 0.52" (119mm x 64mm x 13.2mm)
Efficiency up to 96%
Excellent thermal performance
Over-Current and Short Circuit Protection
Over-Temperature protection
Monotonic startup into pre-bias loads
400kHz Fixed switching frequency
Remote On/Off control (Positive or Negative logic)
External Trim adjust and Remote Sense functions
Operating Temp. Range -40°C to +105°C
RoHS Compliant
Product Overview
for extended temperature operation.
The 4:1 input voltage 1000 Watt single output ICF DC-DC
converter provides a precisely regulated dc output. The output
voltage is fully isolated from the input, allowing the output to be
positive or negative polarity and with various ground
connections. The enclosed full brick package meets the most
rigorous performance standards in an industry standard
footprint for process control (24Vin), and Commercial-Off-TheShelf (28Vin) applications.
The converter’s high efficiency and high power density are
accomplished through use of high-efficiency synchronous
rectification technology, advanced electronic circuit,
packaging and thermal design thus resulting in a high
reliability product. The converter operates at a fixed frequency
of 400kHz and follows conservative component derating
guidelines.
The ICF Series includes an external TRIM adjust, Remote
Sense and remote ON/OFF control. Threaded through holes are
provided to allow easy mounting or the addition of a heat sink
Product is designed and manufactured in the USA.
Part Number Structure and Ordering Guide
Description
Product Family
Form Factor
Vout*
Output Current
Vin Range
On/Off Control Logic
Specific Customer Configuration
RoHS Compliant
Part Number Structure
I
Definition and Options
C
F
0
4
4
2
V
1
P
X
X
IC= Industrial Class
F = Full Brick
01 = 12Vout, 04 = 24Vout, 05 = 28Vout, 06 = 48Vout, 07 = 53Vout
Max Iout in Amps
V1 = 9 to 36V
N = Negative, P = Positive (Standard)
Customer Code, Omit for Standard
C RoHS 6/6 Compliant
*NOTE: Some part number combinations might not be available. Please contact the factory for non-standard or special order products.
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MDC_ICF_A08 Page 1 of 25
ICF Series
Wide Input 1000 Watt Isolated Full Brick DC-DC
Electrical Specifications – All Models
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 24VDC, unless otherwise specified. Specifications are subject to change without notice.
Parameter
Notes
Min
Typ
Max
Units
Absolute Maximum Ratings
Input Voltage
Continuous
0
Transient (100ms)
Operating Temperature (See Note 1)
Baseplate (100% load) Standard model
Storage Temperature
40
V
50
V
-40
105
°C
-55
125
°C
Isolation Characteristics and Safety
Isolation Voltage
Input to Output
2250
Input to Baseplate & Output to Baseplate
1500
Isolation Capacitance
Isolation Resistance
10
Insulation Safety Rating
Vdc
Vdc
9000
pF
20
MΩ
Basic
Designed to meet UL/cUL 60950, IEC/EN60950-1
Agency Approvals
Feature Characteristics
Fixed Switching Frequency
200
Input Current and Output Voltage Ripple
kHz
400
Output Voltage Trim Range
Adjustable via TRIM (Pin 12)
Remote Sense Compensation
Between each SENSE input and its corresponding
OUT pin
Output Overvoltage Protection
Non-latching
114
Overtemperature Shutdown (Baseplate)
Non-latching (Vin=9V; 12V, 24/36V)
Auto-Restart Period
Applies to all protection features
Turn-On Time from Vin
kHz
110
%
1
V
122
130
%
108
112
115
°C
1.7
2
2.3
s
Time from UVLO to Vo=90%VOUT(NOM)
Resistive load
480
517
530
ms
ICF0442V1 and ICF0536V1
20
27
35
ms
ICF0621V1 and ICF0719V1
20
35
50
ms
ICF0442V1 and ICF0536V1
4
7
11
ms
ICF0621V1 and ICF0719V1
7
15
25
ms
ON state
Pin open = ON or
2
12
V
Control Current
Leakage current
Turn-On Time from ON/OFF Control Time from ON to
Vo=90%VOUT(NOM) Resistive load
Rise Time Vout from 10% to 90%
60
ON/OFF Control – Positive Logic
OFF state
Control current
Sinking
0.16
mA
0
0.8
V
0.3
0.36
mA
ON/OFF Control – Negative Logic
ON state
Pin shorted to – ON/OFF pin or
0
0.8
V
OFF state
Pin open = OFF or
2
12
V
Thermal Characteristics
Thermal resistance Baseplate to Ambient
Converter soldered to 5” x 3.5” x 0.07”,
4 layer/2Oz copper FR4 PCB.
3.3
°C/W
1. A thermal management device, such as a heatsink, is required to ensure proper operation of this device. The thermal management medium is required to
maintain baseplate < 105ºC for full rated power.
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MDC_ICF_A08 Page 2 of 25
ICF Series
Wide Input 1000 Watt Isolated Full Brick DC-DC
Electrical Specifications - ICF0184V1xC
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s) and 0.9” heatsink, Vin = 14VDC, unless otherwise specified. Specifications are subject to change
without notice.
Parameter
Notes
Min
Typ
Max
Units
Input Characteristics
9
14
36
V
Turn-on Threshold
8.2
8.5
8.8
V
Turn-off Threshold
7.7
8.0
8.3
V
Lockout Hysteresis Voltage
0.4
0.55
0.7
V
89
A
Operating Input Voltage Range
Input Under Voltage Lockout
Maximum Input Current
Non-latching
Vin = 9V, 80% Load
92
Vin = 12V, 100% Load
600
Vin = 14V, Output Shorted
Input Stand-by Current
Converter Disabled
Input Current @ No Load
Converter Enabled
450
Minimum Input Capacitance (external)1)
See Table 1
1000
2
4
mA
550
690
mA
0.19
µF
2
A s
ARMS
Inrush Transient
Input Terminal Ripple Current, iC
3.65
25 MHz bandwidth, 100% Load (Fig. 5)
A
mARMS
Output Characteristics
Output Voltage Range
Output Voltage Set Point Accuracy
(No load)
11.64
12.00
12.36
V
11.90
12.00
12.10
V
%
Output Regulation
Over Line
Vin = 9V to 36V
0.05
0.10
Over Load
Vin = 14V, Load 0% to 100%
0.05
0.150
%
0.005
0.015
15.6
%/ºC
V
Temperature Coefficient
14
Overvoltage Protection
Output Ripple and Noise – 20 MHz bandwidth
External Load Capacitance
1)
Output Current Range (See Fig. A)
Current Limit Inception
RMS Short-Circuit Current
100% Load,
See Table 1 for external components
120
mVPK-PK
40
mVRMS
See Table 1
Vin = 12V – 36V
0
84
A
Vin = 9V
0
67.2
A
109.2
A
109.2
A
Vin = 12V – 36V
92.4
9V ≤ Vin < 12V
73.5
Non-latching, Continuous
100.8
7
ARMS
±500
mV
800
µs
Vin = 14V
93.0
%
Vin = 12V
92.3
%
Vin = 14V
95.4
%
Vin = 12V
95.0
%
Dynamic Response
Load Change 50%-100%-50%, di/dt = 0.5A/µs
Co = 2 x 470 µF/70mΩ
Settling Time to 1% of VOUT
Efficiency
100% Load
50% Load
1)
Section “Input and Output Capacitance”
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MDC_ICF_A08 Page 3 of 25
ICF Series
Wide Input 1000 Watt Isolated Full Brick DC-DC
Electrical Specifications - ICF0442V1xC
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 24VDC, unless otherwise specified. Specifications are subject to change without notice.
Parameter
Notes
Min
Typ
Max
Units
Input Characteristics
9
24
36
V
Turn-on Threshold
8.2
8.5
8.8
V
Turn-off Threshold
7.7
8.0
8.3
V
Lockout Hysteresis Voltage
0.4
0.55
0.7
V
Vin = 9V, 80% Load
89
A
Vin = 12V, 100% Load
92
A
Operating Input Voltage Range
Input Under Voltage Lockout
Maximum Input Current
Non-latching
350
Vin = 24V, Output Shorted
Input Stand-by Current
Converter Disabled
Input Current @ No Load
Converter Enabled
330
Minimum Input Capacitance (external)1)
ESR < 0.1 Ω
1000
4
mA
420
530
mA
0.19
µF
2
A s
ARMS
Inrush Transient
Input Terminal Ripple Current, iC
mARMS
2
3.65
25 MHz bandwidth, 100% Load (Fig. 5)
Output Characteristics
Output Voltage Range
Output Voltage Set Point Accuracy
(No load)
23.62
24.00
24.36
V
23.90
24.00
24.10
V
Output Regulation
Over Line
Vin = 9V to 36V
0.05
0.10
%
Over Load
Vin = 24V, Load 0% to 100%
0.05
0.10
%
0.005
0.015
31.2
%/ºC
V
200
320
mVPK-PK
80
mVRMS
Temperature Coefficient
27.36
Overvoltage Protection
Output Ripple and Noise – 20 MHz bandwidth
External Load Capacitance1)
Output Current Range (See Fig. A)
Current Limit Inception
RMS Short-Circuit Current
(Fig. 6) 100% Load,
See Table 1 for external components
Full Load (resistive)
(over operating temp range)
50
CEXT
ESR
1000
4700
µF
10
100
mΩ
Vin = 12V – 36V
0
42
A
Vin = 9V
0
33.5
A
Vin = 12V – 36V
46
50.2
54.6
A
9V ≤ Vin < 12V
37
49
54.6
A
Non-latching, Continuous
2.0
3.1
6.5
ARMS
±600
mV
Dynamic Response
Load Change 50%-75%-50%, di/dt = 1A/µs
Co = 2 x 470 µF/70mΩ
±400
Load Change 50%-100%-50%, di/dt = 1A/µs
Co = 2 x 470 µF/70mΩ
±700
mV
500
µs
Settling Time to 1% of VOUT
Efficiency
Vin = 24V
100% Load
50% Load
1)
93.6
94.6
95.3
%
Vin = 12V
92.4
93.4
94.0
%
Vin = 24V
95.0
96.0
96.4
%
Vin = 12V
94.7
95.7
96.3
%
Section “Input and Output Capacitance”
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MDC_ICF_A08 Page 4 of 25
ICF Series
Wide Input 1000 Watt Isolated Full Brick DC-DC
Electrical Specifications - ICF0536V1xC
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 24VDC, unless otherwise specified. Specifications are subject to change without notice.
Notes
Parameter
Operating Input Voltage Range
Input Under Voltage Lockout
Min
Typ
Max
Units
9
24
36
V
8.2
8.5
8.8
V
Non-latching
Turn-on Threshold
Turn-off Threshold
7.7
8.0
8.3
V
Lockout Hysteresis Voltage
0.4
0.55
0.7
V
Vin = 9V, 80% Load
89
A
Vin = 12V, 100% Load
92
A
Maximum Input Current
Vin = 24V, Output Shorted
330
Input Stand-by Current
Converter Disabled
Input Current @ No Load
Converter Enabled
400
Minimum Input Capacitance (external)1)
ESR < 0.1 Ω
1000
4
mA
480
600
mA
0.19
µF
2
A s
ARMS
Inrush Transient
Input Reflected-Ripple Current, iC
25 MHz bandwidth, 100% Load (Fig. 5)
mARMS
2
2.5
Output Characteristics
Nominal Output Voltage
Output Voltage Set Point Accuracy
(No load)
27.56
28.00
28.42
V
27.90
28.00
28.10
V
%
Output Regulation
Over Line
Vin = 9V to 36V
0.05
0.10
Over Load
Vin = 24V, Load 0% to 100%
0.05
0.10
%
0.005
0.015
%/ºC
36.4
V
220
360
mVPK-PK
50
80
mVRMS
Temperature Coefficient
31.9
Overvoltage Protection
Output Ripple and Noise – 20 MHz bandwidth
External Load Capacitance1)
Output Current Range (See Fig. A)
(Fig. 6) 100% Load,
See Table 1 for external components
Full Load (resistive)
(over operating temp range)
Vin = 12V – 36V
RMS Short-Circuit Current
4700
µF
10
100
mΩ
0
36
A
0
28.8
A
Vin = 12V – 36V
39.6
46.8
A
9V ≤ Vin < 12V
31.7
46.8
A
Non-latching
1.7
2.5
6.4
ARMS
±430
mV
Vin = 9V
Current Limit Inception
CEXT
ESR
1000
Dynamic Response
Load Change 50%-75%-50%, di/dt = 1A/µs
See Table 1 for external components
±330
Load Change 50%-100%-50%, di/dt = 1A/µs
See Table 1 for external components
±600
mV
500
µs
Settling Time to 1% of VOUT
Efficiency
Vin = 24V
100% Load
50% Load
1)
94.5
95.5
96.2
%
Vin = 12V
93.0
93.8
94.5
%
Vin = 24V
95.5
96.2
97.0
%
Vin = 12V
94.3
95.4
96.2
%
Section “Input and Output Capacitance”
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MDC_ICF_A08 Page 5 of 25
ICF Series
Wide Input 1000 Watt Isolated Full Brick DC-DC
Electrical Specifications - ICF0621V1xC
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 24VDC, unless otherwise specified. Specifications are subject to change without notice.
Parameter
Notes
Min
Typ
Max
Units
Input Characteristics
9
24
36
V
Turn-on Threshold
8.2
8.5
8.8
V
Turn-off Threshold
7.7
8.0
8.3
V
Lockout Hysteresis Voltage
0.4
0.55
0.7
V
Vin = 9V, 80% Load
89
A
Vin = 12V, 100% Load
92
A
Operating Input Voltage Range
Input Under Voltage Lockout
Maximum Input Current
Non-latching
400
Vin = 24V, Output Shorted
Input Stand-by Current
Converter Disabled
Input Current @ No Load
Converter Enabled
370
Minimum Input Capacitance (external)1)
ESR < 0.1 Ω
1000
4
mA
470
560
mA
0.19
µF
2
A s
ARMS
Inrush Transient
Input Terminal Ripple Current, iC
mARMS
2
0.9
25 MHz bandwidth, 100% Load (Fig. 5)
Output Characteristics
Output Voltage Range
Output Voltage Set Point Accuracy
(No load)
47.28
48.00
48.92
V
47.80
48.00
48.20
V
Output Regulation
Over Line
Vin = 9V to 36V
0.05
0.10
%
Over Load
Vin = 24V, Load 0% to 100%
0.05
0.10
%
0.005
0.015
62.4
%/ºC
V
100
150
mVPK-PK
50
mVRMS
Temperature Coefficient
54.7
Overvoltage Protection
Output Ripple and Noise – 20 MHz bandwidth
External Load Capacitance1)
Output Current Range (See Fig. A)
Current Limit Inception
RMS Short-Circuit Current
(Fig. 6) 100% Load,
See Table 1 for external components
Full Load (resistive)
(over operating temp range)
25
CEXT
ESR
470
3000
µF
10
100
mΩ
Vin = 12V – 36V
0
21
A
Vin = 9V
0
16.8
A
Vin = 12V – 36V
23.1
25.2
27.3
A
9V ≤ Vin < 12V
18.48
20.16
27.3
A
1.0
1.6
3.3
ARMS
Non-latching, Continuous
Dynamic Response
Load Change 50%-75%-50%, di/dt = 1A/µs
See Table 1 for external components
±480
±560
mV
Load Change 50%-100%-50%, di/dt = 1A/µs
See Table 1 for external components
±880
±1150
mV
500
Settling Time to 1% of VOUT
µs
Efficiency
Vin = 24V
100% Load
50% Load
1)
94.3
95.0
95.7
%
Vin = 12V
93.2
93.9
94.6
%
Vin = 24V
95.3
96.0
96.7
%
Vin = 12V
94.9
95.6
96.3
%
Section “Input and Output Capacitance”
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MDC_ICF_A08 Page 6 of 25
ICF Series
Wide Input 1000 Watt Isolated Full Brick DC-DC
Electrical Specifications - ICF0719V1xC
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 24VDC, unless otherwise specified. Specifications are subject to change without notice.
Notes
Parameter
Operating Input Voltage Range
Input Under Voltage Lockout
Min
Typ
Max
Units
9
24
36
V
8.2
8.5
8.8
V
Non-latching
Turn-on Threshold
Turn-off Threshold
7.7
8.0
8.3
V
Lockout Hysteresis Voltage
0.4
0.55
0.7
V
Vin = 9V, 80% Load
89
A
Vin = 12V, 100% Load
92
A
Maximum Input Current
Vin = 24V, Output Shorted
300
Input Stand-by Current
Converter Disabled
Input Current @ No Load
Converter Enabled
360
Minimum Input Capacitance (external)1)
ESR < 0.1 Ω
1000
4
mA
460
560
mA
0.19
µF
2
A s
ARMS
Inrush Transient
Input Reflected-Ripple Current, iC
25 MHz bandwidth, 100% Load (Fig. 5)
mARMS
2
0.8
Output Characteristics
Nominal Output Voltage
Output Voltage Set Point Accuracy
(No load)
52.20
53.00
54.02
V
52.78
53.00
53.22
V
%
Output Regulation
Over Line
Vin = 9V to 36V
0.05
0.10
Over Load
Vin = 24V, Load 0% to 100%
0.05
0.10
%
0.005
0.015
%/ºC
64.7
69.4
V
70
140
mVPK-PK
16
50
mVRMS
Temperature Coefficient
60.4
Overvoltage Protection
Output Ripple and Noise – 20 MHz bandwidth
External Load Capacitance1)
Output Current Range (See Fig. A)
(Fig. 6) 100% Load,
See Table 1 for external components
Full Load (resistive)
(over operating temp range)
Vin = 12V – 36V
RMS Short-Circuit Current
2200
µF
10
100
mΩ
0
19
A
15.2
A
Vin = 12V – 36V
20.9
22.8
24.7
A
9V ≤ Vin < 12V
16.7
18.2
24.7
A
Non-latching
0.8
1.8
3.0
ARMS
Vin = 9V
Current Limit Inception
CEXT
ESR
470
0
Dynamic Response
Load Change 50%-75%-50%, di/dt = 1A/µs
See Table 1 for external components
±420
±510
mV
Load Change 50%-100%-50%, di/dt = 1A/µs
See Table 1 for external components
±850
±1100
mV
500
Settling Time to 1% of VOUT
µs
Efficiency
Vin = 24V
100% Load
50% Load
1)
94.9
95.7
96.4
%
Vin = 12V
93.4
94.1
95.0
%
Vin = 24V
95.3
96.2
96.9
%
Vin = 12V
95.1
95.4
96.5
%
Section “Input and Output Capacitance”
www.murata-ps.com/support
MDC_ICF_A08 Page 7 of 25
ICF Series
Wide Input 1000 Watt Isolated Full Brick DC-DC
Environmental and Mechanical Specifications
NOTE: Specifications are subject to change without notice.
Parameter
Min
Notes
Typ
Max
Units
Environmental
Operating Humidity
Non-condensing
95
%
Storage Humidity
Non-condensing
95
%
RoHS Compliance
See Murata Website http://www.murata-ps.com/en/support/rohs-compliance.html for the
complete RoHS Compliance statement
Shock and Vibration (See Note 1)
Designed to meet MIL-STD-810G for functional shock and vibration.
Water washability
Not recommended for water wash process. Contact the factory for more information.
Mechanical
8.55
Ounces
242
Grams
Unit Weight
Through Hole Pins Diameter
Pins 3, 3A, 4, 4A, 5, 6, 8 and 9
Pins 1, 2, 10, 11 and 12
Through Hole Pins Material
0.079
0.081
0.083
2.006
2.057
2.108
mm
0.038
0.04
0.042
Inches
0.965
1.016
1.667
mm
Pins 3, 3A, 4, 4A, 5, 6 , 8 and 9
Copper Alloy
Pins 1, 2, 10, 11 and 12
Through Hole Pin Finish
TB3 or “Eco Brass”
All pins
10µ” Gold over nickel
Case Dimension
4.7 x 2.5 x 0.52
Inches
119.38 x 63.50 x 13.21
mm
Plastic: Vectra LCP FIT30: ½-16 EDM Finish
Plastic
Aluminum
Case Material
Material
Baseplate
Inches
Flatness
0.010
Inches
0.25
mm
5.4
MHrs
Reliability
Telcordia SR-332, Method I Case 1 50% electrical
stress, 40°C components
MTBF
EMI and Regulatory Compliance
Conducted Emissions
MIL-STD 461F CE102 with external EMI filter network (See Figures 57 and 58)
1. The unit must be properly secured to the interface medium (PCB/Chassis) by use of the threaded inserts of the unit.
Output Power vs. Input Voltage
Output Power [W]
1200
1000
800
600
400
200
0
9
12
15
18
21
24
27
30
33
36
Input Voltage [V]
Figure A: Output Power as function of input voltage.
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MDC_ICF_A08 Page 8 of 25
ICF Series
Wide Input 1000 Watt Isolated Full Brick DC-DC
TECHNICAL NOTES
Input Fusing
The ICF converters do not provide internal fusing and therefore in
some applications external input fuse may be required. Use of
external fuse is also recommended if there is possibility for input
voltage reversal. For greatest safety, it is recommended to use
fast blow fuse in the ungrounded input supply line.
Input Reverse Polarity Protection
The ICF converters do not have input reverse polarity. If input
voltage polarity is reversed, internal diodes will become forward
biased and draw excessive current from the power source. If the
power source is not current limited or input fuse not used, the
converter could be permanently damaged.
Input Undervoltage Protection
Input undervoltage lockout is standard with this converter. The ICF
converter will start and regulate properly if the ramping-up input
voltage exceeds Turn-on threshold of typ. 8.5V (See Specification)
and remains at or above Turn-on Threshold.
The converter will turn off when the input voltage drops below the
Turn-off Threshold of typical 8V (See specification) and converter
enters hiccup mode and will stay off for 2 seconds. The converter
will restart after 2 seconds only if the input voltage is again above
the Turn-on Threshold.
The built-on hysteresis and 2 second hiccup time prevents any
unstable on/off operation at the low input voltage near Turn-on
Threshold.
User should take into account for IR and inductive voltage drop in
the input source and input power lines and make sure that the
input voltage to the converter is always above the Turn-off
Threshold voltage under ALL OPERATING CONDITIONS.
Start-Up Time
The start-up time is specified under two different scenarios: a)
Startup by ON/OFF remote control (with the input voltage above
the Turn-on Threshold voltage) and b) Start-up by applying the
input voltage (with the converter enabled via ON/OFF remote
control).
The startup times are measured with maximum resistive load as:
a) the interval between the point when the ramping input voltage
crosses the Turn-on Threshold and the output voltage reaches
90% of its nominal value and b) the interval between the point
when the converter is enabled by ON/OFF remote control and time
when the output voltage reaches 90% of its nominal value.
When converter is started by applying the input voltage with
ON/OFF pin active there is delay of 500msec that was intentionally
provided to prevent potential startup issues especially at low input
voltages
Input Source Impedance
Because of the switching nature and negative input impedance of
DC-DC converters, the input of these converters must be driven
from the source with both low AC impedance and DC input
regulation.
The ICF converters are designed to operate without external
components as long as the source voltage has very low
impedance and reasonable voltage regulation. However, since this
is not the case in most applications an additional input capacitor is
required to provide proper operations of the ICF converter.
Specified values for input capacitor are recommendation and need
to be adjusted for particular application. Due to large variation
between applications some experimentation may be needed.
In many applications, the inductance associated with the
distribution from the power source to the input of the converter
can affect the stability and in some cases, if excessive, even
inhibit operation of the converter. This becomes of great
consideration for input voltage at 12V or below.
The DC input regulation, associated with resistance between input
power source and input of the converter, plays significant role in
particular in low input voltage applications such as 12V battery
systems.
Note that input voltage at the input pins of the connector must
never degrade below Turn-off threshold under all load operating
conditions.
Note that in applications with high pulsating loads additional input
as well as output capacitors may be needed. In addition, for EMI
conducted measurement, due to low input voltage it is
recommended to use 5µH LISNs instead of typical 50µH LISNs.
Input/Output Filtering
Input Capacitor
Minimum required input capacitance, mounted close to the input
pins of the converter, is 1000µF with ESR < 0.1Ω.
Several criteria need to be met when choosing input capacitor: a)
type of capacitor, b) capacitance to provide additional energy
storage, c) RMS current rating, d) ESR value that will ensure that
output impedance of the input filter is lower than input impedance
of the converter and its variation over the temperature.
Since inductance of the input power cables could have significant
voltage drop due to rate of change of input current di(in)/dt during
transient load operation, an external capacitor on the output of the
converter is required to reduce di(in)/dt. Another constraint is
minimum rms current rating of the input capacitors which is
application dependent. One component of input rms current
handled by input capacitor is high frequency component at
switching frequency of the converter (typ. 400kHz) and is
specified under “Input terminal ripple current” iC. Typical values at
full rated load and 24 Vin are provided in Section “Characteristic
Waveforms” for each model and are in range of 2.5A (28Vout) –
3.6A (24Vout). It is recommended to use ceramic capacitors for
attenuating this component for input terminal ripple current, which
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MDC_ICF_A08 Page 9 of 25
ICF Series
Wide Input 1000 Watt Isolated Full Brick DC-DC
is also required to meet requirement for conducted EMI (See EMI
Section). The second component of the input ripple current is due
to pulsating load current being reflected to the input and
electrolytic capacitors usually used for this purpose need to be
selected accordingly. Using several electrolytic capacitors in
parallel on the input is recommended.
ESR of the electrolytic capacitors, need to be carefully chosen
taken into account temperature dependence.
Output Capacitor
Similar considerations apply for selecting external output
capacitor. For additional high frequency noise attenuation use of
ceramic capacitors is recommended while in order to provide
stability of the converter during high pulsating load high value
electrolytic capacitor is required. It is recommended to use several
electrolytic capacitors in parallel in order to reduce effective ESR.
Note that external output capacitor also reduces slew rate of the
input current during pulsating load transients as discussed above.
We recommend 2 x 470uF (
