OBSOLETE PRODUCT

Triple Output/TWR Models
www.murata-ps.com
Isolated, High Reliability 1" x 2" DC/DC Converters
OBSOLETE PRODUCT
Last time buy: 04 January 2013
Typical units
FEATURES
PRODUCT OVERVIEW

±12V/±15V and 3.3V/5V outputs

10-18V, 18-36V or 36-75V inputs
Packaged in 1" x 2" encapsulated modules, the TWR
22W series DC/DC converters offer three outputs
arranged as a unipolar low voltage supply and a
higher voltage bipolar output pair. The unipolar
section supplies either +3.3V at 4A maximum or
+5V at 3A maximum. The bipolar outputs are either
±12Vdc at 300mA maximum or ±15Vdc at 250mA
and are ideal for op amps, linear or analog circuits.
A single TWR converter can power applications
with combined analog and digital circuits such as a
CPU-controlled voice switch, embedded telephone
modem or analytical instruments.

Up to 22.5 Watts total output power with overtemperature shutdown

To 87% efficiency; 80-100mV Ripple and Noise

1" x 2" x 0.5" encapsulated package

1500Vdc isolation for both outputs

Certified to UL 60950-1, CSA-C22.2 No. 60950-1,
EN60950-1 safety approvals, 2nd Edition

Extensive self-protection with short circuit
shutdown

Output overvoltage and overcurrent protection

Input under and overvoltage shutdown

Ideal for mixed analog/digital systems
The input section is fully isolated from the outputs
up to 1500Vdc minimum using Basic insulation.
Three wide input ranges are available including
10-18V (12Vdc nominal), 18-36V (24Vdc nomimal)
or 36-75V (48Vdc nominal). Peak-to-peak output
ripple/noise is typically 80-100mV at full load.
Efficiencies range up to 87%.
The TWR 22W series outputs will limit their current
if driven to overload and may be short circuited
indefinitely without damage. The inputs will shut
down if input voltage is either over or under limits
or has reversed input voltage. These converters
will operate at higher temperatures with adequate
airflow.
The unipolar output features line and load regulation of ±1%. Excellent dynamic response assures
transient load change settling within 100 microseconds. Other convenience features include a remote
On/Off control to turn the outputs on via digital
logic, CPU bit, control transistor or a relay.
Fabrication uses DATEL’s advanced surface
mount automated pick-and-place assembly and
computer-controlled parameter testing. All TWR
22W series are certified to safety requirements in
UL, EN60950-1 and CSA-C22.2 No.60950-1, 2nd
Edition.
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For full details go to
www.murata-ps.com/rohs
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MDC_TWR22.C03 Page 1 of 9
Triple Output/TWR Models
Isolated, High Reliability 1" x 2" DC/DC Converters
Performance Specifications and Ordering Guide 
Input
Output
R/N (mvp-p)
Model
TWR-3.3/4-12/300-D12-C
TWR-3.3/4-12/300-D24-C
TWR-3.3/4-12/300-D48N-C
TWR-3.3/4-15/250-D12-C
TWR-3.3/4-15/250-D24-C
TWR-3.3/4-15/250-D48N-C
TWR-5/3-12/300-D12-C
TWR-5/3-12/300-D24-C
TWR-5/3-12/300-D48N-C
TWR-5/3-15/250-D12-C
TWR-5/3-15/250-D24-C
TWR-5/3-15/250-D48N-C
VOUT
Volts
3.3
±12
3.3
±12
3.3
±12
3.3
±15
3.3
±15
3.3
±15
5
±12
5
±12
5
±12
5
±15
5
±15
5
±15
IOUT
Amps
4
0.3
4
0.3
4
0.3
4
0.25
4
0.25
4
0.25
3
0.3
3
0.3
3
0.3
3
0.25
3
0.25
3
0.25
Typ.
40
70
Input Current
Regulation (Max.)
Max.
60
150
Line
±0.05%
±0.35%
Load
±0.4%
±3%
VIN Nom.
(Volts)
Range
(Volts)
No Load
(mA)
Full Load
(Amps)
Efficiency
Min.
Typ.
Packag
(Case/
Pinout)
12
9-18
170
2.00
82%
85%
C39/P61
C39/P61
Please contact Murata Power Solutions for further information.
C39/P61
C39/P61
80
100
80
100
80
100
80
100
80
100
40
45
80
45
65
45
T WR - 5 / 3 - 12 / 300
100
150
100
150
100
150
100
150
100
150
75
65
100
60
100
60
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±0.05%
±0.5%
±0.4%
±0.625%
±0.05%
±0.4%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±0.2%
±4%
±0.2%
±4%
±0.3%
±4%
24
18-36
25
1.00
83%
86%
C39/P61
48
36-75
25
0.50
85%
87%
C39/P61
12
9-18
120
2.20
81.5%
84%
C39/P61
24
18-36
90
1.08
83%
86%
C39/P61
48
36-75
25
0.53
85%
87%
C39/P61
12
9-18
170
2.26
81%
83%
C39/P61
24
18-36
80
1.09
83%
86%
C39/P61
48
36-75
45
0.54
85%
87.5%
C39/P61
D48 N - C
RoHS-6 Hazardous Substance Compliance
(does not claim EU RoHS exemption 7b, lead in solder)
Output Configuration
Wide Range Input
On/Off Control Polarity
Nominal Primary Output Voltage
Input Voltage Range
See page 9 for complete Part Number Structure and Ordering Information
Maximum Primary Output Current
Maximum Auxiliary Output Current
Nominal Auxiliary Output Voltage
MECHANICAL SPECIFICATIONS
2.00
(50.8)
PLASTIC CASE
0.49
(12.5)
STANDOFF
0.020 (0.5)
0.040 ±0.002 DIA.
(1.016 ±0.051)
0.20 MIN
(5.1)
1.800
(45.72)
0.200
(5.08)
0.300
(7.62)
0.10
(2.5)
4
1
5
2
6
3
7
0.800
0.600 (20.32)
(15.24)
1.00
(25.4)
I/O Connections
Pin
Function P61
1
+Input
2
–Input
3
On/Off Control
4
+12V/15V Output
5
–12V/15V Output
6
Common
7
+3.3/5V Output
Alternate pin length and/or other output
voltages are available under special
quantity order.
Dimensions are in inches (mm) shown for ref. only.
Third Angle Projection
Tolerances (unless otherwise specified):
.XX ± 0.02 (0.5)
.XXX ± 0.010 (0.25)
Angles ± 2˚
Components are shown for reference only
BOTTOM VIEW
0.10
(2.5)
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MDC_TWR22.C03 Page 2 of 9
Triple Output/TWR Models
Performance/Functional Specifications
Isolated, High Reliability 1" x 2" DC/DC Converters
Typical @ TA = +25°C under nominal line voltage, nominal output voltage, natural air convection,
external caps and full-load conditions unless noted. 
Input
Input Voltage Range
See Ordering Guide
Start-Up Threshold: 
12V Models
24V Models
48V Models
9V minimum, 9.5V typical
16.5V minimum, 17V typical
34V minimum, 35V typical
Undervoltage Shutdown: 
12V Models
24V Models
48V Models
8V minimum, 8.5V typical
15.5V minimum, 16.3V typical
32.5V minimum, 34.5V typical
Overvoltage Shutdown:
12V Models
24V Models
48V Models
20V typical, 21V maximum
37V typical, 38V maximum
78.5V typical, 81V maximum
Reflected (Back) Ripple Current 
12mA typical, 20mAp-p maximum
See Ordering Guide
25mA typical, 50mA maximum
170mA typical, 200mA maximum
TBD
Remote On/Off Control 
Positive Logic (no model suffix)
Off = ground pin to +1.2V maximum
On = open pin to +VIN maximum
2mA maximum
On = ground pin to +1.2V maximum
Off = open pin to +VIN maximum
18mA maximum
Current
Negative Logic (N model suffix)
Current
Output
VOUT Range
See Ordering Guide
VOUT Accuracy:
3.3V or 5V Output
±12V or ±15V Outputs
±1% of VNOM
±10% of VNOM (See Technical Notes)
Temperature Coefficient
±0.02% of VOUT range/°C
Minimum Loading:
3.3V or 5V Output
±12V or ±15V Outputs
See Technical Notes
No minimum load
20% minimum of nominal output current,
balanced load
Ripple/Noise (20MHz BW) 
See Ordering Guide
Line/Load Regulation 
See Ordering Guide & Technical Notes
Efficiency
See Ordering Guide
Maximum Capacitive Loading:
3.3V or 5V Output
±12V or ±15V Outputs
TBD
TBD
Isolation:
Input to Output Voltage
Resistance
Capacitance
Isolation Safety Rating
1500Vdc minimum
100MΩ
470pF
Functional insulation
Current Limit Inception: (98% of VOUT)
3.3V Output
5V Output
±12V Outputs
±15V Outputs
5 Amps minimum, 6.2 Amps maximum
4 Amps minimum, 5.3 Amps maximum
0.36 Amps minimum, 1 Amp maximum
0.36 Amps minimum, 0.9 Amps maximum
Short-Circuit Detection:
3.3V or 5V Output
±12V or ±15V Outputs
Magnetic feedback
Magnetic feedback plus voltage clamp
Short-Circuit Current:
3.3V or 5V Output
±12V or ±15V Outputs
Overvoltage Protection:
3.3V Output
5V Output
±12V or ±15V Outputs
Continuous, output shorted to ground
3.3V=3.8Vdc minimum, 4.2Vdc maximum
5V= 6.2Vdc minimum, 7.7Vdc maximum
30Vdc maximum
Method: magnetic feedback
Dynamic Characteristics
Input Current:
Full Load Conditions
No Load VIN = nominal
12V and 24V Models
48V Models
Low-Line Voltage (VIN = VMIN, full load)
Short-Circuit Potection Method
Short Circuit Duration (no damage)
Dynamic Load Response (50-100% loadstep)
3.3V or 5V Output
150μsec to ±1.5% of final value
±12V or ±15V Outputs
150μsec to ±10% of final value
Start-Up Time
VIN to VOUT regulated
TBD msec for VOUT = nominal
Switching Frequency
330kHz ±20kHz
Environmental
Calculated MTBF
TBD
Operating Temperature: (Ambient) 
No Derating (Natural convection)
With Derating
–40 to +65°C
See Derating Curves
Operating Case Temperature
–40 to +100°C maximum
Storage Temperature
–40 to +120°C
Thermal Protection/Shutdown
+110°C minimum to 120°C maximum
Relative Humidity
10% to 90%, non-condensing
Physical
Dimensions
See Mechanical Specifications
Case and Header Material
Black Diallyl Phthalate plastic
Pin Dimensions/Material
0.04" (1.016mm) dia. Gold-plated copper
alloy with nickel underplate.
Weight
TBD
Electromagnetic Interference
TBD
Safety
Certified to UL/cUL 60950-1 CSA-C22.2
No.234 IEC/EN 60950-1, 2nd Edition
 All models are tested/specified with two external 0.047µF output capacitors. These capacitors
are necessary to accommodate our test equipment and may not be required to achieve specified performance in your applications. All models are stable and regulate within spec under
no-load conditions.
 Input Reflected Ripple Current is tested/specified over a 20MHz bandwidth. Input filtering is
CIN = 33µF, 100V tantalum; CBUS = 220µF, 100V electrolytic; LBUS = 12µH. See Technical Notes.
 For consistent operation, the instantaneous input voltage for full output load must not go below
the low shutdown voltage AT ALL TIMES. Beware of excessive voltage drop from long input
wiring. For reliable startup, be sure to apply input power promptly and fully as a step function.
 Mean Time Before Failure is calculated using the Telcordia (Belcore) SR-332 Method 1, Case
3, ground fixed conditions, TCASE = +25°C, full load, natural air convection.
 The On/Off Control may be driven with external logic or the application of appropriate voltages
(referenced to Common). The On/Off Control input should use either an open collector/open drain
transistor or logic gate which does not exceed +VIN. The On/Off Control may be supplied with with
negative logic (LO = on, HI = off) using the "N" model suffix.
 Maximum Power Derating curves indicate an average current at nominal input voltage. At higher
temperatures and/or lower airflow, the DC/DC converter will tolerate brief full current outputs if
the total RMS current over time does not exceed the derating curve.
 All models are fully operational and meet published specifications, including cold start at –40°C.
 Output noise may be further reduced by adding an external filter. See I/O Filtering and Noise
Reduction.
Current limiting with hiccup autorestore.
Remove overload for recovery.
 The outputs share a common isolated return. The two output sections are not isolated from
each other.
 Regulation specifications describe the deviation as the line input voltage or output load current
is varied from a nominal midpoint value to either extreme.
 The outputs will not accept appreciable reverse current without possible damage.
2 Amps maximum
1 Amp maximum
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MDC_TWR22.C03 Page 3 of 9
Triple Output/TWR Models
Isolated, High Reliability 1" x 2" DC/DC Converters
Absolute Maximum Ratings
Input Voltage:
Continuous or transient
12V Models
24V Models
48V Models
–0.3V minimum or +18V maximum
–0.3V minimum or +36V maximum
–0.3V minimum or +75V maximum
On/Off Control (Pin 1)
–0.3V minimum or +VIN maximum
Input Reverse-Polarity Protection
None. Install external fuse.
Output Overvoltage Protection
VOUT +20% maximum
Output Current
Current limited. Devices can
withstand sustained output short
circuits without damage.
Storage Temperature
–40 to +120°C
Lead Temperature (soldering 10 sec. max.)
+280°C
These are stress ratings. Exposure of devices to greater than any of these conditions may
adversely affect long-term reliability. Proper operation under conditions other than those
listed in the Performance/Functional Specifications Table is not implied.
T E C H N I C A L
N O T E S
Input Undervoltage Shutdown and Start-Up Threshold
Under normal start-up conditions, devices will not begin to regulate
until the ramping-up input voltage exceeds the Start-Up Threshold Voltage.
Once operating, devices will not turn off until the instantaneous input
voltage drops below the Undervoltage Shutdown limit. Subsequent restart
will not occur until the input is brought back up to the Start-Up Threshold.
This built-in hysteresis avoids any unstable on/off situations occurring at a
single input voltage. However, you should be aware that poorly regulated
input sources and/or higher input impedance sources (including long power
leads) which have outputs near these voltages may cause cycling of the
converter outputs.
Ripple Current and Output Noise
All TWR converters are tested and specified for input reflected ripple current (also called Back Ripple Current) and output noise using specified filter
components and test circuit layout as shown in the figures below. Input
capacitors must be selected for low ESR, high AC current-carrying capability at the converter’s switching frequency and adequate bulk capacitance.
The switching nature of DC/DC converters requires this low AC impedance
to absorb the current pulses reflected back from the converter’s input.
Load Dependency and Regulation
The high voltage bipolar output section derives its regulation as a slave
to the low voltage unipolar output. Be aware that large load changes on
the unipolar section will change the voltage somewhat on the bipolar
section. To retain proper regulation, the bipolar voltage section must have
a minimum load of at least 10% of rated full output. With this minimal
load (or greater), the high voltage bipolar section will meet all its regulation specifications. If there is no load, the output voltage may exceed the
regulation somewhat.
Input Fusing
Certain applications and/or safety agencies require fuses at the inputs
of power conversion components. Fuses should also be used if there is the
possibility of sustained, non-current limited reverse input polarity. DATEL
recommends fast-blow type fuses approximately twice the maximum input
current at nominal input voltage but no greater than 5 Amps. Install these
fuses in the high side (ungrounded input) power lead to the converter.
Input Voltage
Fuse Value
12 Volts
4 Amps
24 Volts
2 Amps
48 Volts
1 Amp
Input Source Impedance
The external source supplying input power must have low AC impedance. Failure to insure adequate low AC impedance may cause stability
problems, increased output noise, oscillation, poor settling and aborted
start-up. The converter’s built-in front end filtering will be sufficient in most
applications. However, if additional AC impedance reduction is needed,
consider adding an external capacitor across the input terminals mounted
close to the converter. The capacitor should have low internal Equivalent
Series Resistance (ESR) and low inductance. Often, two or more capacitors are used in parallel. A ceramic capacitor gives very low AC impedance
while a parallel electrolytic capacitor offers improved energy storage.
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Figure 2. Measuring Input Ripple Current
Output Overcurrent Detection
Overloading the power converter’s output for extended periods (but not a
short circuit) at high ambient temperatures may overheat the output components and possibly lead to component failure. Brief moderate overcurrent
operation (such as charging up reasonably-sized external bypass capacitors
when first starting) will not cause problems. The TWR series include current
limiting to avoid heat damage. However, you should remove a sustained
overcurrent condition promptly as soon as it is detected. Combinations of
low airflow and/or high ambient temperature for extended periods may
cause overheating even though current limiting is in place.
Current Return Paths
Make sure to use adequately sized conductors between the output
load and the Common connection. Avoid simply connecting high current
returns only through the ground plane unless there is adequate copper
thickness. Also, route the input and output circuits directly to the Common
pins. Failure to observe proper wiring may cause instability, poor regulation,
increased noise, aborted start-up or other undefined operation.
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MDC_TWR22.C03 Page 4 of 9
Triple Output/TWR Models
Isolated, High Reliability 1" x 2" DC/DC Converters
Safety Considerations
Isolation Considerations
The TWR’s must be installed with consideration for any local safety,
certification or regulatory requirements. These vary widely but generally
are concerned with properly sized conductors, adequate clearance between
higher voltage circuits, life testing, thermal stress analysis of components and
flammability of components.
These converters use both transformer and optical coupling to isolate the
inputs from the outputs. Ideal “floating” isolation implies ZERO CURRENT flowing between the two Common return sections of the input and output up to the
working isolation voltage limit. Real-world isolation on this converter includes
both an AC current path (through some small coupling capacitance) and some
DC leakage current between the two ground systems. To avoid difficulties
in your application, be sure that there are not wideband, high amplitude AC
difference voltages between the two ground systems. In addition, ground difference voltages applied by your external circuits which exceed the isolation
voltage, even momentarily, may damage the converter’s isolation barrier. This
can either destroy the converter or instantly render it non-isolated.
Remote On/Off Control
The TWR models include an input pin which can turn on or shut off the
converter by remote signal. For positive logic models (no model number
suffix), if this pin is left open, the converter will always be enabled as long
as proper input power is present. On/Off signal currents are referred to the
Input Common pin on the converter. There is a short time delay of several milliseconds (see the specifications) for turn on, assuming there is no significant
external output capacitance.
The On/Off Control may also be supplied with negative logic (LO = on, HI =
off) using the “N” model number suffix. For negative logic, the On/Off pin must
be grounded or pulled LOW to turn on the unit. Positive logic models must
have this control pin pulled down for shutoff. Negative logic models must pull
up this control pin for shutoff.
Dynamic control of this On/Off input is best done with either a mechanical relay, solid state relay (SSR), an open collector or open drain transistor,
CPU bit or a logic gate. The pull down current is 18mA max. for "N" models.
Observe the voltage limits listed in the specifications for proper operation.
Suggested circuits are shown below.
CMOS
LOGIC
ON/OFF
CONTROL
CONTROLLER
SIGNAL
GROUND
COMMON
Figure 3. On/Off Control With An External CMOS Gate
If the current continues to increase, the converter will enter short circuit
operation and the PWM controller will shut down. Following a time-out
period, the converter will automatically attempt to restart. If the short circuit
is detected again, the converter will shut down and the cycle will repeat. This
operation is called hiccup autorecovery. Please be aware that excessive external output capacitance may interfere with the hiccup autorestart.
Output Filtering and Noise Reduction
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The amount of capacitance to add depends on the placement of the cap
(near the converter versus near the load), the distance from the converter to
the load (and resulting series inductance), the topology and locations of load
elements if there are multiple parallel loads and the nature of the loads. For
switching loads such as CPU’s and logic, this last item recommends that small
bypass capacitors be placed directly at the load. Very high clock speeds suggest smaller caps unless the instantaneous current changes are high. If the
load is a precision high-gain linear section, additional filtering and shielding
may be needed.
Many applications will need no additional capacitance. However, if more
capacitance is indicated, observe these factors:
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As the output load increases above its maximum rated value, the converter
will enter current limiting mode. The output voltage will decrease and the
converter will essentially deliver constant power. This is commonly called
power limiting.
All switching DC/DC converters produce wideband output noise which radiates both through the wiring (conducted emission) and is broadcast into the
air (radiated emission). This output noise may be attenuated by adding a small
amount of capacitance in parallel with the output terminals. Please refer to the
maximum output capacitance in the Specifications.
+INPUT
HI = ON
LO = OFF
(for positive
On/Off)
Current Limiting and Short Circuit Condition
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1. Understand the noise-reduction objective. Are you improving the switching
threshold of digital logic to reduce errors? (This may need only a small
amount of extra capacitance). Or do you need very low noise for a precision
linear “front end”?
2. Use just enough capacitance to achieve your objective. Additional capacitance trades off increasing instability (actually adding noise rather than
reducing it), poor settling response, possible ringing or outright oscillation by the converter. Excessive capacitance may also disable the hiccup
autorestart. Do not exceed the maximum output capacitance specification.
Figure 4. On/Off Control With An External Transistor (positive logic)
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MDC_TWR22.C03 Page 5 of 9
Triple Output/TWR Models
Isolated, High Reliability 1" x 2" DC/DC Converters
3. Any series inductance considerably complicates the added capacitance
therefore try to reduce the inductance seen at the converter’s output. You
may need to add BOTH a cap at the converter end and at the load (effectively creating a Pi filter) for the express purpose of reducing the phase
angle which is seen by the converter’s output loop controller. This tends
to hide (decouple) the inductance from the controller. Make sure your
power conductors are adequate for the current and reduce the distance
to the load as much as possible. Very low noise applications may require
more than one series inductor plus parallel caps.
4. Oscillation or instabilility can occur at several frequencies. For this
reason, you may need both a large electrolytic or tantalum cap (carrying most of the capacitance) and a small wideband parallel ceramic
cap (with low internal series inductance). Always remember that inside
real world capacitors are distributed trace inductance (ESL) and series
resistance (ESR). Make sure the input AC impedance is very low before
trying to improve the output.
It is probably more important in your system that all heat is periodically
removed rather than having very high airflow. Consider having the total
enclosure completely recycled at least several times a minute. Failure to
remove the heat causes heat buildup inside your system and even a small
fan (relative to the heat load) is quite effective. A very rough guide for typical enclosures is one cubic foot per minute of exhausted airflow per 100
Watts of internal heat dissipation.
Efficiency Curves
These curves indicate the ratio of output power divided by input power
at various input voltages and output currents times 100%. All curves are
measured at +25°C ambient temperature and adequate airflow.
Typical Performance Curves for TWR Series
5. It is challenging to offer a complete set of simple equations in reasonable closed form for the added output capacitance. Part of the difficulty is
accurately modeling your load environment. Therefore your best success
may be a combination of previous experience and empirical approximation.
47273ERIES/UTPUT0OWERVS!MBIENT4EMPERATURE —#
Maximum Current and Temperature Derating Curves
/UTPUT0OWER7ATTS
The curves shown below indicate the maximum average output current
available versus the ambient temperature and airflow. All curves are done
approximately at sea level and you should leave an additional margin for
higher altitude operation and possible fan failure. (Remember that fans are
less efficient at higher altitudes). These curves are an average – current
may be greater than these values for brief periods as long as the average
value is not exceeded.
The “natural convection” area of the curve is that portion where selfheating causes a small induced convective airflow around the converter
without further mechanical forced airflow from a fan. Natural convection
assumes that the converter is mounted with some spacing to adjacent components and there are no nearby high temperature parts. Note that such
self-heating will produce an airflow of typically 25 Linear Feet per Minute
(LFM) without a fan. Heat is removed both through the mounting pins and
the surface of the converter.
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Many systems include fans however it is not always easy to measure
the airflow adjacent to the DC/DC converter. Simply using the cubic feet
per minute (CFM) rating of the fan is not always helpful since it must be
matched to the volume of the enclosure, the outside ambient temperature,
board spacing, the intake area and total internal power dissipation.
Most PWM controllers, including those on the TWR’s, will tolerate operation up to about +100 degrees Celsius. If in doubt, attach a thermal sensor
to the package near the output components and measure the surface
temperature after allowing a proper warm-up period. Remember that the
temperature inside the output transistors at full power will be higher than
the surface temperature therefore do not exceed operation past approximately +100 deg. C on the surface. As a rough indication, any circuit which
you cannot touch briefly with your finger warrants further investigation.
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MDC_TWR22.C03 Page 6 of 9
Triple Output/TWR Models
Isolated, High Reliability 1" x 2" DC/DC Converters
Typical Performance Curves for TWR Series
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MDC_TWR22.C03 Page 7 of 9
Triple Output/TWR Models
Isolated, High Reliability 1" x 2" DC/DC Converters
Typical Performance Curves for TWR Series
472$
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%FFICIENCY
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MDC_TWR22.C03 Page 8 of 9
Triple Output/TWR Models
Isolated, High Reliability 1" x 2" DC/DC Converters
P A R T
N U M B E R
S T R U C T U R E
T WR - 5 / 3 - 12 / 300 - D48 N - C
Output Configuration:
T = Triple
RoHS-6 Hazardous Substance Compliance
(does not claim EU RoHS exemption 7b, lead in solder)
On/Off Control Polarity
Blank = Positive Logic
N = Negative Logic
Wide Range Input
Nominal Primary Output
Voltage (+3.3 or +5 Volts)
Input Voltage Range:
D12 = 10-18 Volts (12V nominal)
D24 = 18-36 Volts (24V nominal)
D48 = 36-75 Volts (48V nominal)
Maximum Primary Output
Current in Amps
Note: Some model number
combinations may not be
available. Contact Murata
Power Solutions.
Maximum Auxiliary Output
Currents in mA from each output
Nominal Auxiliary Output
Voltages (±12 or ±15 Volts)
Murata Power Solutions, Inc.
11 Cabot Boulevard, Mansfield, MA 02048-1151 U.S.A.
ISO 9001 and 14001 REGISTERED
This product is subject to the following operating requirements
and the Life and Safety Critical Application Sales Policy:
Refer to: http://www.murata-ps.com/requirements/
Murata Power Solutions, Inc. makes no representation that the use of its products in the circuits described herein, or the use of other
technical information contained herein, will not infringe upon existing or future patent rights. The descriptions contained herein do not imply
the granting of licenses to make, use, or sell equipment constructed in accordance therewith. Specifications are subject to change without
notice.
© 2012 Murata Power Solutions, Inc.
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MDC_TWR22.C03 Page 9 of 9