1000
WATT
FXP
SERIES
DC/DC CONVERTERS
2401 Stanwell Drive, Concord Ca. 94520
Ph: 925-687-4411
Fax: 925-687-3333
www.calex.com
Email: sales@calex.com
ECO 170203-4, 170227-2, 170802-1, 171121-
1
Page 1 of 22
Features
Description
The 4:1 Input Voltage 1000 Watt Single FXP DC/DC
converter provides a regulated dc output with capability
for paralleling up to three converters delivering up to
2.8kW. Current sharing among converters is achieved
using droop method and does not require a current
share pin. The output voltage is fully isolated from the
input, allowing the output to be positive or negative
polarity and with various ground connections. The 1000
Watt FXP meets the most rigorous performance
standards in an industry standard footprint for mobile
(12Vin), process control (24Vin), and military COTS
(28Vin) applications.
The 4:1 Input Voltage 1000W FXP includes trim and
remote ON/OFF. Threaded through holes are provided
to allow easy mounting or addition of a heatsink for
extended temperature operation.
The converters 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. Converter operates
at a fixed frequency and follows conservative component
de-rating guidelines.
Product is designed and manufactured in the USA.
●
4:1 Input voltage range
●
High power density
●
Parallel Operation - up to 3 units (2.8kW)
● Small size 2.5” x 4.7” x 0.52”
●
Efficiency up to 96%
●
Excellent thermal performance with metal case
●
Over-Current and Short Circuit Protection
●
Over-Temperature protection
●
Auto-restart
●
Monotonic startup into pre bias
●
Constant frequency
●
Remote ON/OFF
●
Good shock and vibration damping
●
Temperature Range -40ºC to +105ºC
Available.
●
RoHS Compliant
Model
Input Range
VDC
Vout
VDC
Iout
ADC
Min Max
24S24.42FXP (ROHS) 9 36 24 42
24S28.36FXP (ROHS) 9 36 28 36
24S48.21FXP (ROHS) 9 36 48 21
24S53.19FXP (ROHS) 9 36 53 19
1. Negative Logic ON/OFF feature available. Add “-N” to the
part number when ordering. i.e. 24S24.42FXP-N (ROHS)
2. Designed to meet MIL-STD-810G for functional shock and
vibration. The unit must be properly secured to the interface
medium (PCB/Chassis) by use of the threaded inserts of the
unit.
3. 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.
4. Non-Standard output voltages are available. Please contact
the factory for additional information.
1000
WATT
FXP
SERIES
DC/DC CONVERTERS
2401 Stanwell Drive, Concord Ca. 94520
Ph: 925-687-4411
Fax: 925-687-3333
www.calex.com
Email: sales@calex.com
ECO 170203-4, 170227-2, 170802-1, 171121-
1
Page 2 of 22
Electrical Specifications
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 24VDC, unless otherwise specified. Specifications are subject to
change without notice.
All Models
Parameter Notes Min Typ Max Units
Absolute Maximum Ratings
Input Voltage Continuous 0
40 V
Transient (100ms)
50 V
Operating Temperature
Baseplate (100% load) -40
105 °C
Storage Temperature
-55
125 °C
Isolation Characteristics and Safety
Isolation Voltage Input to Output 2250
V
Input to Baseplate & Output to Baseplate 1500
V
Isolation Capacitance
9000
pF
Isolation Resistance
10 20
MΩ
Insulation Safety Rating
Basic
Designed to meet UL/cUL 60950, IEC/EN 60950-1
Feature Characteristics
Fixed Switching Frequency
200
kHz
Input Current and Output Voltage Ripple 400 kHz
Output Voltage Trim Range
Adjustable via TRIM (Pin 12) 60 110 %
Remote Sense Compensation Between SENSE+ and +OUT pins 1 V
Output Overvoltage Protection Non-latching 114 122 130 %
Overtemperature Shutdown (Baseplate) Non-latching (Vin=9V; 12V, 24/36V) 108 112 115 °C
Auto-Restart Period Applies to all protection features 1.7 2 2.3 s
Turn-On Delay Time from Vin Time from UVLO to
Vo=90%V
OUT
(NOM)
Resistive
load
480 517 530 ms
Turn-On Delay Time from ON/OFF Control
(From ON to 90%VOUT(NOM) Resistive load)
24S24.42FXP & 24S28.36FXP 20 27 35
ms
24S48.21FXP & 24S53.19FXP 20 35 50
ms
Rise Time (Vout from 10% to90%) 24S24.42FXP & 24S28.36FXP 4 7 11 ms
24S48.21FXP & 24S53.19FXP 7 15 25 ms
ON/OFF Control – Positive Logic
ON state Pin open = ON or 2 12 V
Control Current Leakage current
0.16 mA
OFF state 0 0.8 V
Control current Sinking 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 layers/ 2Oz copper FR4 PCB.
3.3 °C/W
1000
WATT
FXP
SERIES
DC/DC CONVERTERS
2401 Stanwell Drive, Concord Ca. 94520
Ph: 925-687-4411
Fax: 925-687-3333
www.calex.com
Email: sales@calex.com
ECO 170203-4, 170227-2, 170802-1, 171121-
1
Page 3 of 22
Electrical Specifications (Continued):
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 24VDC, unless otherwise specified. Specifications are subject to change
without notice.
24S24.
42
FXP
Parameter Notes Min Typ Max Units
Input Characteristics
Operating Input Voltage Range 9 24 36
V
Input Under Voltage
Lockout
Non
-
latching
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
Maximum Input Current Vin = 9V, 80% Load 89 A
Vin = 12V, 100% Load 92 A
Vin = 24V, Output Shorted 350 mARMS
Input Stand-by Current Converter Disabled 3 4 mA
Input Current @ No Load Converter Enabled 330 420 500 mA
Minimum Input Capacitance (external)1) ESR < 0.1 Ω 1000 µF
Inrush Transient 0.19 A2s
Input Terminal Ripple Current, iC
2) 20 MHz bandwidth, 100% Load (Fig.24) 1.6 ARMS
Output Characteristics
Output Voltage Range Over Load, Line and temperature 23.549 24.301
V
Output Voltage Set Point Accuracy (No load) 24.179 24.240 24.301 V
Output Regulation
Over Line Vin = 9V to 36V 0.05 0.10 %
Over Load Vin = 24V, Load 0% to 100% 2.37 2.5 2.63 %
Temperature Coefficient 0.005 0.015 %/ºC
Overvoltage Protection 27.4 31.2 V
Output Ripple and Noise 20 MHz bandwidth See Fig. 6 and Table 1 for details. Full load,
20 MHz bandwidth.
60 120 mVPK-PK
15 35 mVRMS
External Load Capacitance1), 2) Full Load (resistive)
C
EXT
(over operating temp range) ESR
1000 4700 µF
mΩ
10 100
Output Current Range (See Fig. A) Vin = 12V – 36V 0 42 A
Vin = 9V 0 33.6 A
Current Limit Inception Vin = 12V – 36V 46.2 50.2 54.6 A
9V ≤ Vin < 12V 37 49 54.6
A
RMS Short-Circuit Current Non-latching, Continuous 2.7 5 ARMS
Dynamic Response2)
Load Change 50%
-
75%
-
50%, di/dt =
1A/µs
See Fig.
21
and Table 1 for C
EXT
.
560 800
mV
P
-
P
Load Change 50%-100%-50%, di/dt = 1A/µs See Fig 22 and Table 1 for CEXT. 1100 1600 mVP-P
Settling Time to 1% of VOUT 700 µs
Efficiency
100% Load Vin = 24V 93.6 94.6 95.3 %
Vin = 12V 92.4 93.4 94.1 %
50% Load Vin = 24V 94.8 95.6 96.4 %
Vin = 12V 94.7 95.4 96.3 %
1)
Section “Input and Output Capacitance” and Table 1 (Section “Test Configuration”)”
2)
See
Section “Test Configuration” for details. Output voltage deviation is measured peak to peak (includes switching ripple and voltage droop).
1000
WATT
FXP
SERIES
DC/DC CONVERTERS
2401 Stanwell Drive, Concord Ca. 94520
Ph: 925-687-4411
Fax: 925-687-3333
www.calex.com
Email: sales@calex.com
ECO 170203-4, 170227-2, 170802-1, 171121-
1
Page 4 of 22
Electrical Specifications (Continued):
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 24VDC, unless otherwise specified. Specifications are subject to change
without notice.
1)
Section “Input and Output Capacitance” and Table 1 (Section “Test Configuration”)
2)
See
Section “Test Configuration” for details. Output voltage deviation is measured peak to peak (includes switching ripple and voltage droop).
24S28.36FXP
Parameter Notes Min Typ Max
Units
Operating Input Voltage Range 9 24 36
V
Input Under Voltage
Lockout
Non
-
latching
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
Maximum Input Current Vin = 9V, 80% Load 89 A
Vin = 12V, 100% Load 92 A
Vin = 24V, Output Shorted 330 mARMS
Input Stand-by Current Converter Disabled 3 4 mA
Input Current @ No Load Converter Enabled 400 460 560 mA
Minimum Input Capacitance (external)1) ESR < 0.1 Ω 1000 µF
Inrush Transient 0.19
A
2
s
Input Reflected Ripple Current, iC
2) 20 MHz bandwidth, 100% Load (Fig. 26) 1.3 ARMS
Output Characteristics
Nominal Output Voltage Over Load, Line and temperature 27.463 28.347
V
Output Voltage Set Point Accuracy (No load) 28.205 28.276 28.347
V
Output Regulation
Over Line Vin = 9V to 36V
0.05 0.1
%
Over Load Vin = 24V, Load 0% to 100% 2.37 2.5 2.63 %
Temperature Coefficient 0.005
0.015
%/ºC
Overvoltage Protection 31.9 36.4 V
Output Ripple and Noise See Fig. 6 and Table 1 for details. Full load
20 MHz bandwidth.
50 100 mVPK-PK
12 25 mVRMS
External Load Capacitance1),2) Full Load (resistive)
CEXT
(over operating temp range) ESR
1000 4700 µF
mΩ
10 100
Output Current Range (See Fig. A) Vin = 12V – 36V 0 36 A
Vin = 9V 0 28.8 A
Current Limit Inception Vin = 12V – 36V 39.6 46.8 A
9V ≤ Vin < 12V 31.7 46.8
A
RMS Short-Circuit Current Non-latching 1.8 2.5 ARMS
Dynamic Response
Load Change 50%-75%-50%, di/dt = 1A/µs See Fig. 27 and Table 1 for CEXT. 500 720 mV
Load Change 50%-100%-50%, di/dt = 1A/µs See Fig. 28 and Table 1 for CEXT. 1000 1500 mV
Settling Time to 1% of VOUT 700 µs
Efficiency
100% Load Vin = 24V 94.8 95.6 96.3 %
Vin = 12V 93.0 93.8 94.5 %
50% Load Vin = 24V 95.6 96.4 97.1 %
Vin =
12V
94.3 95.4 96.2 %
1000
WATT
FXP
SERIES
DC/DC CONVERTERS
2401 Stanwell Drive, Concord Ca. 94520
Ph: 925-687-4411
Fax: 925-687-3333
www.calex.com
Email: sales@calex.com
ECO 170203-4, 170227-2, 170802-1, 171121-
1
Page 5 of 22
Electrical Specifications (Continued):
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 24VDC, unless otherwise
specified. Specifications are subject to change without notice.
24S48.21FXP
Parameter Notes Min Typ Max Units
Input Characteristics
Operating Input Voltage Range 9 24 36
V
Input Under Voltage
Lockout
Non
-
latching
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
Maximum Input Current Vin = 9V, 80% Load 89 A
Vin = 12V, 100% Load 92 A
Vin = 24V, Output Shorted 350 mARMS
Input Stand-by Current Converter Disabled 3 4 mA
Input Current @ No Load Converter Enabled 360 460 550 mA
Minimum Input Capacitance (external)1) ESR < 0.1 Ω 1000 µF
Inrush Transient 0.19
A
2
s
Input Terminal Ripple Current, iC
2) 20 MHz bandwidth, 100% Load (Fig. 36) 1.6 ARMS
Output Characteristics
Output Voltage Range Over Load, Line and temperature 47.086 48.601
V
Output Voltage Set Point Accuracy (No load) 48.359 48.480 48.601 V
Output Regulation
Over Line Vin = 9V to 36V 0.05 0.10 %
Over Load Vin = 24V, Load 0% to 100% 2.37 2.5 2.63 %
Temperature Coefficient 0.005 0.015 %/ºC
Overvoltage Protection 54.7 62.4 V
Output Ripple and Noise See Fig. 6 and Table 1 for details. Full load
20 MHz bandwidth.
100 240 mVPK-PK
30 80 mVRMS
External Load Capacitance1), 2) Full Load (resistive)
C
EXT
(over operating temp range) ESR
470 3000 µF
mΩ
10 100
Output Current Range (See Fig. A) Vin = 12V – 36V 0 21 A
Vin = 9V 0 16.8 A
Current Limit Inception Vin = 12V – 36V 23.1 25.2 27.3 A
9V ≤ Vin < 12V 18.5 24.2 27.3
A
RMS Short-Circuit Current Non-latching, Continuous 1.4 2.4 ARMS
Dynamic Response2)
Load Change 50%-75%-50%, di/dt = 1A/µs See Fig. 33. 660 950
mV
P
-
P
Load Change 50%-100%-50%, di/dt = 1A/µs See Fig. 34. 1320 1900 mVP-P
Settling Time to 1% of VOUT 600 µs
Efficiency
100% Load Vin = 24V 94.3 95 95.7 %
Vin = 12V 93.2 93.9 94.6 %
50% Load Vin = 24V 95.3 96 96.7 %
Vin = 12V 95.1 95.8 96.5 %
1)
Section “Input and Output Capacitance” and Table 1 (Section “Test Configuration”)
2)
See
Section “Test Configuration” for details. Output voltage deviation is measured peak to peak (includes switching ripple and voltage droop).
1000
WATT
FXP
SERIES
DC/DC CONVERTERS
2401 Stanwell Drive, Concord Ca. 94520
Ph: 925-687-4411
Fax: 925-687-3333
www.calex.com
Email: sales@calex.com
ECO 170203-4, 170227-2, 170802-1, 171121-
1
Page 6 of 22
Electrical Specifications (Continued):
Conditions: TA = 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 24VDC, unless otherwise specified. Specifications are subject to change
without notice.
1)
Section “Input and Output Capacitance” and Table 1 (Section “Test Configuration”).
2)
See
Section “Test Configuration” for details. Output voltage deviation is measured peak to peak (includes switching ripple and voltage droop).
24S53.19FXP
Parameter Notes Min Typ Max
Units
Operating Input Voltage Range 9 24 36
V
Input Under Voltage
Lockout
Non
-
latching
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
Maximum Input Current Vin = 9V, 80% Load 89 A
Vin = 12V, 100% Load 92 A
Vin = 24V, Output Shorted 330 mARMS
Input Stand-by Current Converter Disabled 2 4 mA
Input Current @ No Load Converter Enabled 400 460 560 mA
Minimum Input Capacitance (external)1) ESR < 0.1 Ω 1000 µF
Inrush Transient 0.19
A
2
s
Input Reflected-Ripple Current, iC
25
MHz
bandwidth, 100% Load (Fig
.
6
)
1.2 A
RMS
Output Characteristics
Nominal Output Voltage Over Load, Line and temperature 51.991 53.664
V
Output Voltage Set Point Accuracy (No load) 53.396 53.530 53.664
V
Output Regulation
Over Line Vin = 9V to 36V
0.05 0.1
%
Over Load Vin = 24V, Load 0% to 100% 2.37 2.5 2.63 %
Temperature Coefficient 0.005
0.015
%/ºC
Overvoltage Protection 60.4 68.9 V
Output Ripple and Noise See Fig. 6 and Table 1 for details. Full load
20 MHz bandwidth
100 240 mVPK-PK
30 80 mVRMS
External Load Capacitance1) Full Load (resistive)
CEXT
(over operating temp range) ESR
470 2200 µF
mΩ
10 100
Output Current Range (See Fig. A) Vin = 12V – 36V 0 19 A
Vin = 9V 0 15.2 A
Current Limit Inception Vin = 12V – 36V 20.9 22.8 24.7 A
9V ≤ Vin < 12V 16.7 20 24.7
A
RMS Short-Circuit Current Non-latching 1 2 ARMS
Dynamic Response2)
Load Change 50%-75%-50%, di/dt = 1A/µs See Fig. 39. 550 800 mV
P
-
P
Load Change 50%-100%-50%, di/dt = 1A/µs See Fig. 40. 1100 1600 mVP-P
mV
Settling Time to 1% of VOUT 600 µs
Efficiency
100% Load Vin = 24V 94.7 95.5 96.2 %
Vin = 12V 93.3 94 94.8 %
50% Load
Vin =
24V
95.5 96.2 97
%
Vin = 12V 94.8 95.5 96.2 %
1000
WATT
FXP
SERIES
DC/DC CONVERTERS
2401 Stanwell Drive, Concord Ca. 94520
Ph: 925-687-4411
Fax: 925-687-3333
www.calex.com
Email: sales@calex.com
ECO 170203-4, 170227-2, 170802-1, 171121-
1
Page 7 of 22
Environmental and Mechanical Specifications. Specifications are subject to change without notice.
Parameter Note Min Typ Max Units
Environmental
Operating Humidity
Non-condensing 95 %
Storage Humidity Non-condensing 95 %
ROHS Compliance1 See Calex Website http://www.calex.com/RoHS.html for the complete RoHS Compliance
statement
Shock and Vibration 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
Weight 8.55 Ounces
242 Grams
Through Hole Pins Diameter
Pins 3, 3A, 4, 4A, 5, 6, 8 and 9 0.079 0.081 0.083 Inches
2.006 2.057 2.108 mm
Pins 1, 2, 10, 11 and 12 0.038 0.04 0.042 Inches
0.965 1.016 1.667 mm
Through Hole Pins Material Pins 3, 3A, 4, 4A, 5, 6 , 8 and 9 C14500 or C1100 Copper Alloy
Pins 1, 2, 10, 11 and 12 Brass Alloy TB3 or “Eco Brass”
Through Hole Pin Finish 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
Case Material Plastic: Vectra LCP FIT30: ½-16 EDM Finish
Baseplate
Material Aluminum
Flatness 0.010 Inches
0.25 mm
Reliability
MTBF Telcordia SR-332, Method I Case 1 50% electrical
stress, 40°C components 5.4 MHrs
EMI and Regulatory Compliance
Conducted Emissions MIL-STD 461F CE102 with external EMI filter network (See Figs. 39-41)
Additional Notes:
1 The RoHS marking is as follows
\
Figure A: Output Power as function of input voltage.
0
200
400
600
800
1000
1200
912 15 18 21 24 27 30 33 36
Output Power [W]
Input Voltage [V]
Output Power vs. Input Voltage
1000
WATT
FXP
SERIES
DC/DC CONVERTERS
2401 Stanwell Drive, Concord Ca. 94520
Ph: 925-687-4411
Fax: 925-687-3333
www.calex.com
Email: sales@calex.com
ECO 170203-4, 170227-2, 170802-1, 171121-
1
Page 8 of 22
Operations
Input Fusing
The FXP 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 FXP 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 FXP 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-in 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 FXP 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 FXP 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 also
1000
WATT
FXP
SERIES
DC/DC CONVERTERS
2401 Stanwell Drive, Concord Ca. 94520
Ph: 925-687-4411
Fax: 925-687-3333
www.calex.com
Email: sales@calex.com
ECO 170203-4, 170227-2, 170802-1, 171121-
1
Page 9 of 22
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 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. It is
recommended to use ceramic capacitors for attenuating
this component of input terminal ripple current, which 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. An electrolytic capacitors, usually
used for this purpose, need to be selected accordingly.
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 or very low ESR
electrolytic capacitors is recommended while in order to
provide stability of the converter during high pulsating
loads high value electrolytic capacitor is required. It is
recommended to use several electrolytic capacitors in
parallel in order to reduce effective ESR and support
required RMS pulsating load current. ESR temperature
dependence needs to be taken into account.
Recommended output capacitors for various models,
used for obtaining characteristic waveforms are given in
Table 1 (“Test Configuration” section).
ON/OFF (Pins 1 and 2)
The ON/OFF pin is used to turn the power converter on
or off remotely via a system signal and has positive logic.
A typical connection for remote ON/OFF function is
shown in Fig. 1.
Fig. 1: Circuit configuration for ON/OFF function.
The positive logic version turns on when the +ON/OFF
pin is at logic high and turns off when at logic low. The
converter is on when the +ON/OFF pin is either left open
or external voltage greater than 2V and not more than
12V is applied between +ON/OFF pin –ON/OFF pin. See
the Electrical Specifications for logic high/low definitions.
The negative logic version turns on when the +ON/OFF
pin is at logic low and turns off when at logic high. The
converter is on when the +ON/OFF pin is either shorted
to –ON/OFF pin or kept below 0.8V. The converter is off
when the +ON/OFF pin is either left open or external
voltage not more than 12V is applied between +ON/OFF
pin and –ON/OFF pin. See the Electrical Specifications
for logic high/low definitions.
The +ON/OFF pin is internally pulled up to typically 4.5V
via resistor and connected to internal logic circuit via RC
circuit in order to filter out noise that may occur on the
ON/OFF pin. The -ON/OFF pin is internally connected to
–-INPUT. A properly de-bounced mechanical switch,
open-collector transistor, or FET can be used to drive the
input of the +ON/OFF pin. The device must be capable
of sinking up to 0.36mA at a low level voltage of £ 0.8 V.
During logic high, the typical maximum voltage at
ON/OFF pin (generated by the converter) is 4.5V, and
the maximum allowable leakage current is 160µA. If not
using the remote on/off feature leave the +ON/OFF pin
open.
TTL Logic Level - The range between 0.81V and 2V is
considered the dead-band. Operation in the dead-band
is not recommended.
External voltage for ON/OFF control should not be
applied when there is no input power voltage applied to
the converter.
Output Overcurrent Protection (OCP)
The converter is protected against overcurrent or short
circuit conditions. Upon sensing an overcurrent
condition, the converter will switch to constant current
operation and thereby begin to reduce output voltage.
When the output voltage drops below approx. 50% of
the nominal value of output voltage, the converter will
shut down.
Once the converter has shut down, it will attempt to
restart every 2 seconds until the overload or short
circuit conditions are removed or the output voltage
rises above 45% of its nominal value within 100 msec.
Once the output current is brought back into its
specified range, the converter automatically exits the
hiccup mode and continues normal operation.
In case of startup into short circuit, internal logic detects
short circuit condition and shuts down converter
typically 5 msec after the condition is detected. The
converter will attempt to restart after 2 seconds until
short circuit condition exists.
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Page 10 of 22
Output Overvoltage Protection (OVP)
The converter will shut down if the output voltage
across +OUT (Pins 5 and 6) and –OUT (Pins 8 and 9)
exceeds the threshold of the OVP circuitry. The OVP
circuitry contains its own reference, independent of the
output voltage regulation loop. Once the converter has
shut down, it will attempt to restart every 2 seconds
until the OVP condition is removed.
Note that OVP threshold is set for nominal output
voltage and not trimmed output voltage value or remote
sense voltage.
Overtemperature Protection (OTP)
The FXP converters have non-latching overtemperature
protection. It will shut down and disable the output if
temperature at the center of the base plate exceeds a
threshold of typical 108ºC for 9Vin, 112 ºC for 12Vin and
115 ºC for 24Vin/36Vin. Measured with FXP converter
soldered to 5” x 3.5” x 0.07” 4 layers/ 2 Oz Cooper FR4
PCB.
The converter will automatically restart when the base
temperature has decreased by approximately 20ºC.
Safety Requirements
Basic Insulation is provided between input and the
output. The converters have no internal fuse. To comply
with safety agencies requirements, a fast-acting or time-
delay fuse is to be provided in the unearthed lead.
Recommended fuse values are:
a) 140A for 9V<Vin<18V
b) 90A for 18V<Vin<36V.
Electromagnetic Compatibility (EMC)
EMC requirements must be met at the end-product
system level, as no specific standards dedicated to EMC
characteristics of board mounted component dc-dc
converters exist.
With the addition of a two stage external filter, the FXP
converters will pass the requirements of MILSTD-461F
CE102 Base Curve for conducted emissions. Note that
5uH LISN should be used in order to enable operation of
the converter at low input voltage.
Remote Sense Pins (Pins 10 and 11)
Sense inputs compensate for output voltage inaccuracy
delivered at the load.
The sense input and power Vout pins are internally
connected through 100Ω (SENSE+ to +OUT) and 0 Ω
(SENSE- to –OUT) resistors enabling the converter to
operate without external connection to the Sense. If the
Sense function is not used for remote regulation, the
user should connect SENSE+ (Pin 11) to +OUT (Pins 5
and 6) at the converter pins. Note that SENSE- (Pin 10)
is internally connected to –OUT (Pins 8 and 9) and
should be used for connecting Trim-down resistor when
trimming function is used. Do not connect this pin to
–OUT externally.
Fig. 2: Circuit configuration for Remote sense function.
SENSE+ line must be treated with care in PCB layouts
and should run adjacent to DC signals. If cables and
discrete wiring is used, it is recommended to use twisted
pair, shielded tubing or similar techniques.
The maximum voltage difference between Sense inputs
and corresponding power pins should be kept below
1V, i.e.:
V(SENSE+) - V(+OUT) ≤ 1V
Note that maximum output power is determined by
maximum output current and highest output voltage at
the output pins of the converter:
[V(+OUT) – V(-OUT)]x Iout ≤ Pout rated
Output Voltage Adjust/TRIM (Pin 12)
The TRIM (Pin 12) allows user to adjust output voltage
10% up or -40% down relative to rated nominal voltage
by addition of external trim resistor. Trim resistor should
be mounted close to the converter and connected with
short leads. Internal resistor in the converter used for the
TRIM is high precision 0.1% with temperature coefficient
25 ppm/ ºC. The accuracy of the TRIM is therefore
determined by tolerance of external Trim resistor. If
trimming is not used, the TRIM pin should be left open.
Trim Down – Decrease Output Voltage
Trimming down is accomplished by connecting an
external resistor, Rtrim-down, between the TRIM (pin 12)
and the SENSE- (pin 10), with a value of:
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Page 11 of 22
Rtrim-down =
∆− 9.98[kΩ]
Where,
Rtrim-down = Required value of the trim-down resistor [kΩ]
VO(NOM) = Nominal value of output voltage [V]
VO(REQ) = Required value of output voltage [V]
∆ = ()()
()[%]
Fig. 3: Circuit configuration for Trim-down function
To trim the output voltage 10% (∆=10) down, required
external trim resistance is:
Rtrim-down =
10 − 9.98 = 39.92 kΩ
Trim Up – Increase Output Voltage
Trimming up is accomplished by connecting an external
resistor, Rtrim-up, between the TRIM (pin 12) and the
SENSE+ (pin 11), with a value of:
Rtrim-up = 4.99 ∗ VONOM∗(100+∆)
1.25∆−(100+2∆)
∆ [kΩ]
Fig. 4: Circuit configuration for Trim-up function
To trim the output voltage up, for example 24V to 26.4V,
∆=10 and required external resistor is:
Rtrim-up = 4.99 ∗ 24∗100+10
1.25∗10 −100+2∗10
10 = 1015 kΩ
Note that trimming output voltage more than 10% is not
recommended and OVP may be tripped.
Active Voltage Programming
In applications where output voltage need to be adjusted
actively, an external voltage source, such as for example
a Digital-to-Analog converter (DAC), capable of both
sourcing and sinking current can be used. It should be
connected across with series resistor Rg across TRIM
(Pin 12) and SENSE- (Pin 10). External trim voltage
should not be applied before converter is enabled in
order to provide proper startup output voltage waveform
and prevent tripping overvoltage protection. Please
contact Calex technical representative for more details.
Thermal Consideration
The FXP converter can operate in a variety of thermal
environment. However, in order to ensure reliable
operation of the converter, sufficient cooling should be
provided. The FXP converter is encapsulated in plastic
case with metal baseplate on the top. In order to
improve thermal performance, power components inside
the unit are thermally coupled to the baseplate. In
addition, thermal design of the converter is enhanced by
use of input and output pins as heat transfer elements.
Heat is removed from the converter by conduction,
convection and radiation.
There are several factors such as ambient temperature,
airflow, converter power dissipation, converter orientation
how converter is mounted as well as the need for
increased reliability that need to be taken into account in
order to achieve required performance. It is highly
recommended to measure temperature in the middle of
the baseplate in particular application to ensure that
proper cooling of the converter is provided.
A reduction in the operating temperature of the converter
will result in an increased reliability.
Parallel Operation
The FXP converters are designed for parallel operation.
Current sharing within <10% is achieved using voltage
droop method that eliminates need for current share pin.
Up to three FXP converters with same nominal output
voltage can be connected in parallel with capability to
provide at least 2.8 kW output power. Output voltage
droops linearly with output current with typical voltage
drop of 2.5% for full range of change from zero to
maximum rated current.
When using the FXP converter in parallel operation it is
important to follow below provided recommendations:
1. The FXP converters connected in parallel need to be
close to each other with minimum resistance
between their output power pins. In order to achieve
specified current share accuracy it is necessary to
make connection with shortest possible traces
1000
WATT
FXP
SERIES
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Ph: 925-687-4411
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1
Page 12 of 22
keeping resistance between load and output pins of
each converter symmetric. Any imbalance of the
resistance between output pins and load among
converters in parallel will affect accuracy of current
sharing.
2. ON/OFF pins of the FXP converters need to be
connected together and used to turn-on or turn-off
converters simultaneously.
3. If ON/OFF pin is not used, +ON/OFF pin should be
either left open (Positive logic) or shorted to –
ON/OFF pin (Negative Logic).
4. Remote sense pins:
a. If not used, SENSE+ should be connected
with short traces to +OUT and SENSE- left
open for each converter.
b. If used, should be connected together
among the converters operating in parallel
and with one pair of lines to the load.
5. TRIM Function
a. If not used leave it open.
b. If used, connect all TRIM pins together and
follow instruction described in Output voltage
adjust/TRIM section. For Trim-down, connect
SENSE- pins together and for Trim-up
connect all SENSE+ pins together.
Minimum Load Current
When FXP converters are connected in parallel there will
be always one with highest Vout no load set point. In
case of startup into no load condition, the FXP with
highest Vo set point will turn on and operate while the
other with lower no load set point will be off. Once load
current exceeds typically 4% (maximum 10%) of rated
output current for one FXP the other FXP with lower set
point will turn on and converters will start sharing current.
Note that min load current is only required during startup
to ensure that both converters are on. After that all
converters connected in parallel will operate even if load
current drops to zero.
When Trim function (with trim resistors) is used for the
FXP connected in parallel, if minimum load current is not
provided during initial startup, output voltage will be out
of regulation at 75% of its nominal value. Once minimum
load current is provided, the converter will lower set point
will start operating and output voltage will be in
regulation. After that converters will operate in parallel
even if load current drops to zero.
Maximum Load Current
Maximum load current is given by:
=[1 + 0.9( − 1)]
Where,
- Rated output current of one FXP
– Number of FXPs connected in parallel
The FXP converters connected in parallel will start into
maximum load current (resistive load) when connected
as described above.
Thermal Derating
There are two most common applications: 1) the FXP
converter is thermally attached to a cold plate inside
chassis without any forced internal air circulation; 2) the
FXP converter is mounted in an open chassis on system
board with forced airflow with or without an additional
heatsink attached to the base plate of the FXP converter.
The best thermal results are achieved in application 1)
since the converter is cooled entirely by conduction of
heat from the top surface of the converter to a cold plate
and temperature of the components is determined by the
temperature of the cold plate. There is also some
additional heat removal through the converter’s pins to
the metal layers in the system board. It is highly
recommended to solder pins to the system board rather
than using receptacles. Typical derating output power
and output current are shown in Figs.15-18 as function
of baseplate temperature up to 105C. Note that operating
converter at these limits for prolonged time will affect
reliability.
Soldering Guidelines
The ROHS-compliant through-hole FXP converters use
Sn/Ag/Cu Pb-free solder and ROHS-compliant
component. They are designed to be processed through
wave soldering machines. The pins are 100% matte tin
over nickel plated and compatible with both Pb and Pb-
free wave soldering processes. It is recommended to
follow specifications below when installing and soldering
FXP converters. Exceeding these specifications may
cause damage to the FXP converter.
Wave Solder Guideline For Sn/Ag/Cu based solders
Maximum Preheat Temperature 115 ºC
Maximum Pot Temperature 270 ºC
Maximum Solder Dwell Time 7 seconds
Wave Solder Guideline For Sn/Pb based solders
Maximum Preheat Temperature 105 ºC
Maximum Pot Temperature 250 ºC
Maximum Solder Dwell Time 6 seconds
FXP converters are not recommended for water wash
process. Contact the factory for additional information if
water wash is necessary.
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Page 13 of 22
Test Configuration
Test setup for measuring input reflected ripple current iC, output voltage ripple, startup waveforms and step load transient
waveforms is shown in Figures 5 and 6. External component values are shown in Table 1. Output capacitors are selected
with low ESR. In addition 100 µF/ 24 mΩ capacitor is selected due to quite stable ESR at -40 Co (only 2 x increase) while
capacitors 220 µF/100mΩ and 470 µF/76mΩ have typical increase in ESR of 6 to 8 times at -40 Co.
All waveforms are taken using oscilloscope with BWL =20MHz.
Fig. 5: Test setup for measuring input reflected ripple currents ic.
Fig. 6: Test setup for measuring output voltage ripple, startup and
step load transient waveforms.
Ref.
Des. Manufacturing p/n 24S24.42FXP/ 24S28.36FXP 24S48.21FXP/ 24S53.19FXP
L1 N/A 100nH 100nH
CIN MAL214699108E3 (Vishay) 2 x 470 µF/72mΩ (650mΩ) 2 x 470 µF/76mΩ (650mΩ)
C1 GRM32ER72A475KA12L 10 µF/1210/X7R/100v 10 µF/1210/X7R/100v
C2
PCR1J101MCL1GS (nichicon) 3 x 100 µF/ 63V/ 24 mΩ (48 mΩ) N/A
PCR1K680MCL1GS (nichicon) N/A 3 x 68 µF/ 80V/ 28 mΩ (56 mΩ)
UPS2A221MPD (nichicon) 220 µF/100V/100mΩ 220 µF/100V/ 100mΩ
MAL214699108E3 (Vishay) 470 µF/ 72mΩ (650mΩ) N/A
Table 1: Component values used in test setup from Figs. 5 and 6. Resistance in ( ) represents ESR value at -40C for specified capacitor.
1000
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Page 14 of 22
Characteristic Curves – Efficiency and Power Dissipation
Fig. 7: 24S24.42FXP (ROHS) Efficiency Curve
Fig. 9: 24S28.36FXP (ROHS) Efficiency Curve
Fig. 8: 24S24.42FXP (ROHS) Power Dissipation
Fig. 10: 24S28.36FXP (ROHS) Power Dissipation
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Page 15 of 22
Characteristic Curves – Efficiency and Power Dissipation (Cont’d)
Fig. 11: 24S48.21FXP (ROHS) Efficiency Curve
Fig. 13: 24S53.19FXP (ROHS) Efficiency Curve
Fig. 12: 24S48.21FXP (ROHS) Power Dissipation
Fig. 14: 24S53.19FXP (ROHS) Power Dissipation
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Page 16 of 22
Characteristic Curves – Derating Curves
Fig. 15: 24S24.42FXP (ROHS) Derating Curve
Fig. 17: 24S48.21FXP (ROHS) Derating Curve
Fig. 16: 24S28.36FXP (ROHS) Derating Curve
Fig. 18: 24S53.19FXP (ROHS) Derating Curve
0
100
200
300
400
500
600
700
800
900
1000
1100
25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105
Output Power [W]
Baseplate Temperature [C]
Output Power vs. Base Plate Temperature - 24S24.42FP
Vin=9V Vin=12V, 24V, 36V
0
100
200
300
400
500
600
700
800
900
1000
1100
25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105
Output Power [W]
Baseplate Temperature [C]
Output Power vs. Base Plate Temperature - 24S48.21FP
Vin=9V Vin=12V, 24V, 36V
0
100
200
300
400
500
600
700
800
900
1000
1100
25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105
Output Power [W]
Baseplate Temperature [C]
Output Power vs. Base Plate Temperature - 24S28.36 XP
Vin=9V Vin=12V, 24V, 36V
0
100
200
300
400
500
600
700
800
900
1000
1100
25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105
Output Power [W]
Baseplate Temperature [C]
Output Power vs. Base Plate Temperature - 24S53.19FP
Vin=9V Vin=12V, 24V, 36V
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Page 17 of 22
Characteristic Waveforms (Vin = 24V) – 24S24.42FXP
Fig. 19: Turn-on by ON/OFF transient (with Vin applied) at full rated load
current (resistive load). Top trace (C1): ON/OFF signal, Bottom trace (C4):
Output voltage.
Fig. 21: Output voltage response to load current step change 50% - 75%-
50% (21A–31.5A–21A) with di/dt =1A/µs. Top trace (C4): Output voltage,
Bottom trace (C3): Load current.
Fig. 23: Output voltage ripple at full rated load current.
Fig. 20: Turn-on by Vin transient (converter enabled) at full rated load
current (resistive load). Top trace (C2): Input voltage Vin, Bottom trace
(C4): Output voltage.
Fig. 22: Output voltage response to load current step change 50% - 100%-
50% (21A–42A–21A) with di/dt =1A/µs. Top trace (C4): Output voltage,
Bottom trace (C3): Load current.
Fig. 24: Input reflected ripple current, ic (500mA/mV), measured at input
terminals at full rated load current. RMS input ripple current iC = 3.14*0.5A =
1.07 Arms.(See Fig. 5).
1000
WATT
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Page 18 of 22
Characteristic Waveforms – 24S28.36FXP
Fig. 25: Turn-on by ON/OFF transient (Vin applied) at full rated load current
(resistive). Top Trace (C1): ON/OFF signal, Bottom Trace (C4): Output
voltage.
Fig. 27: Output voltage response to load current step change 50% - 75%-
50% (18A–27A–18A) with di/dt =1A/µs. Top trace (C4): Output voltage,
Bottom trace (C3): Load current.
Fig. 29: Output voltage ripple at full rated load current.
Fig. 26: Turn-on by Vin (converter enabled) transient at full rated load
current (resistive). Top trace (C2): Input voltage Vin, Bottom trace (C4):
Output voltage.
Fig. 28: Output voltage response to load current step change 50% - 100%-
50% (18A–36A–18A) with di/dt =1A/µs. Top trace (C4): Output voltage,
Bottom trace (C3): Load current.
Fig. 30: Input reflected ripple current, ic, measured at input terminals at full
rated load current. Refer to Fig. 2 for test setup. RMS input ripple current
iC = 2.6*0.5A = 1.3Arms.
1000
WATT
FXP
SERIES
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Page 19 of 22
Characteristic Waveforms – 24S48.21FXP
Fig. 31: Turn-on by ON/OFF transient (Vin applied) at full rated load current
(resistive). Top trace (C1): ON/OFF signal, Bottom trace (C4): Output
voltage.
Fig. 33: Output voltage response to load current step change 50% - 75%-
50% (10.5A–15.75A–18A) with di/dt =1A/µs. Top trace (C4): Output voltage,
Bottom trace (C3): Load current.
Fig. 35: Output voltage ripple at full rated load current.
Fig. 32: Turn-on by Vin (ON/OFF high) transient at full rated load current
(resistive). Top trace (C2): Input voltage, Bottom trace (C4): Output
voltage.
Fig. 34: Output voltage response to load current step change 50% - 100%-
50% (10.5A–21A–10.5A) with di/dt =1A/µs. Top trace (C4): Output voltage,
Bottom trace (C3): Load current.
Fig. 36: Input reflected ripple current, ic (500 mA/div.), measured at input
terminals at full rated load current. Refer to Fig. 2 for test setup. RMS input
ripple current iC = 3.12*0.5A = 1.56Arms.
1000
WATT
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SERIES
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Page 20 of 22
Characteristic Waveforms – 24S53.19FXP
Fig. 37: Turn-on by ON/OFF transient (Vin applied) at full rated load
current (resistive). Top trace (C1): ON/OFF signal, Bottom trace (C4):
Output voltage.
Fig. 39: Output voltage response to load current step change 50% - 75%-
50% (9.5A–14.25A–18A) with di/dt =1A/µs. Top trace (C4): Output
voltage, Bottom trace (C3): Load current.
Fig. 41: Output voltage ripple at full rated load current.
Fig. 38: Turn-on by Vin (ON/OFF high) transient at full rated load
current (resistive). Top trace (C2): Input voltage Vin, Bottom trace
(C4): Output voltage.
Fig. 40: Output voltage response to load current step change 50% -
100%- 50% (18A–36A–18A) with di/dt =1A/µs. Top trace (C4): Output
voltage, Bottom trace (C3): Load current.
Fig.42: Input reflected ripple current, ic (500 mA/div.), measured at input
terminals at full rated load current. Refer to Fig. 2 for test setup. RMS
input ripple current iC = 2.34*0.5A = 1.17Arms.
1000
WATT
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SERIES
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1
Page 21 of 22
EMC Consideration
The filter circuit schematic for suggested input filter configuration as tested to meet the conducted emission limits of MILSTD-461F CE102 Base Curve
is shown in Fig. 43. The plots of conducted EMI spectrum measured using 5uH LISNs are shown in Figures 44 and 45.
Note: Customer is ultimately responsible for the proper selection, component rating and verification of the suggested parts based on the end
application.
Component Designator
Des
c
ription
C1, C2, C12, C14 470uF/100V/70mΩ Electrolytic Capacitor (Vishay MAL214699108E3 or equivalent)
C12 2 x 470uF/100V/70mΩ Electrolytic Capacitor (Vishay MAL214699108E3 or equivalent)
C3, C4, C5, C6 4.7nF/1210/X7R/2kV Ceramic Capacitor
C7, C8, C9, C10, C11, C13 10µF/1210/X7R/50V Ceramic Capacitor
L1 CM choke, 130µH, Leakage = 0.6µH (4T on toroid 22.1mm x 13.7 mm x 7.92 mm)
Fig. 43: Typical input EMI filter circuit with component values used to attenuate conducted emissions per MILSTD-461F CE102 Base Curve.
a) Without input filter from Fig. 23 (C9 = 2 x 470µF/50V/70mΩ)
b) With input filter from Fig. 23.
Fig. 44: Input conducted emissions measurement (Typ.) of 24S28.36FXP.
a) Without input filter from Fig. 23 (C9 = 2 x 470µF/50V/70mΩ
b) With input filter from Fig. 23
Fig. 45: Input conducted emissions measurement (Typ.) of 24S53.19FXP.
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Page 22 of 22
Mechanical Specification
Input/ Output Connections
Pin
Label
Function
1 +ON/OFF TTL input with internal pull up, referenced to –-
ON/OFF pin, used to turn converter on and off
2 -ON/OFF Negative input of Remote ON/OFF
3 -INPUT Negative Input Voltage
3A -INPUT Negative Input Voltage
4 +INPUT Positive Input Voltage
4A +INPUT Positive Input Voltage
5 +OUT Positive Output Voltage
6 +OUT Positive Output Voltage
8 -OUT Negative Output Voltage
9 -OUT Negative Output Voltage
10 SENSE- Negative Remote Sense (Used for Trim)
11 SENSE+ Positive Remote Sense
12 TRIM Used to trim output voltage 60% - 100%
Note:
1) Pinout as well as pin number and pin diameter are inconsistent
between manufacturers of the full brick converters. Make sure to
follow the pin function, not the pin number, as well as spec for pin
diameter when laying out your board.
NOTES:
Unless otherwise specified:
All dimensions are in inches [millimeter]
Tolerances: x.xx in. ±0.02 in. [x.x mm ± 0.5mm]
x.xxx in. ±0.010 in. [x.xx mm ± 0.25mm]
Torque fasteners into threaded mounting inserts at 10 in.lbs. or
less. Greater torque may result in damage to unit and void the
warranty.
