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OKI-T/3-W40 Series
Adjustable Output 3-Amp DOSA-SMT DC/DC Converters
PRODUCT OVERVIEW
The OKI-T/3 series are miniature non-isolated Point-of-Load (POL) DC/DC power converters for embedded applications. The module is fully compatible with Distributed-power Open Standards Alliance (DOSA) industry-standard specifications (www.dosapower.com). Applications include powering CPU's, industrial 24V transducers and POS terminals. The wide input range is 16 to 40 Volts DC. The maximum output current is 3 Amps. Based on fixed-frequency synchronous buck converter switching topology, the high power conversion efficient Point of Load (POL) module features programmable output voltage and On/Off control. These converters also include under voltage lock out (UVLO), output short circuit protection, overcurrent and over temperature protections. These units are designed to meet all standard UL/EN/IEC 60950-1 safety certifications and RoHS-6 hazardous substance compliance.
PRELIMINARY
Typical unit
FEATURES

Non-isolated SMT POL DC/DC power module 16-40Vdc input voltage range Programmable output voltage from 0.7525-5.5Vdc 3 Amp output current models Drives 1000 F ceramic capacitive loads High power conversion efficiency 86% at 5 Vout Outstanding thermal derating performance Over temperature and over current protection On/Off control UL/EN/IEC 60950-1 safety (pending) Industry-standard (DOSA) surface-mount package RoHS-6 hazardous substance compliance Contents Description, Connection Diagram, Photograph Ordering Guide, Model Numbering, Product Labeling Mechanical Specifications, Input/Output Pinout Detailed Electrical Specifications Output Voltage Adjustment, Soldering Guidelines Application Notes Performance Data and Oscillograms Page 1 2 3 4 5 6 9
Connection Diagram
+Vin F1 +Vout
On/Off Control
Controller
External DC Power Source
Trim Open = On Closed = Off (Positive On/Off) Common Figure 1. OKI-T/3 Note: Murata Power Solutions strongly recommends an external input fuse, F1. See specifications. Reference and Error Amplifier
Common
For full details go to www.murata-ps.com/rohs
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MDC_OKI-T/3-W40 Series.A01_D8 Page 1 of 12
OKI-T/3-W40 Series
Adjustable Output 3-Amp DOSA-SMT DC/DC Converters
Performance Specifications and Ordering Guide
ORDERING GUIDE Output VOUT (Volts) 0.7525-5.5 0.7525-5.5 Input IIN, IIN, no load full load (mA) (Amps)
40 0.71
Package, C72 Efficiency Min.
86.5%
Root Model OKI-T/3-W40N-C OKI-T/3-W40P-C
R/N (mVp-p) Regulation (Max.) IOUT (Amps Power VIN Nom. Range max) (Watts) Max. Line Load (Volts) (Volts) 3 3 15 15 20 20 0.2% 0.2% 0.25% 0.25% 24 24 16-40 16-40
Typ.
88%
Case C72
0.47 x 0.82 x 0.34 (11.9 x 20.8 x 8.5) 0.47 x 0.82 x 0.34 (11.9 x 20.8 x 8.5)
Pinout P78 P78
40
0.71
86.5%
88%
Dimensions are in inches (mm). These are partial model numbers. Please refer to the part number structure for complete ordering part numbers. All specifications are at nominal line voltage, Vout=nominal (5V for W40 models) and full load, +25 C. unless
otherwise noted. Output capacitors are 1 F ceramic and 10 F electrolytic in parallel. Input cap is 22 F. See detailed specifications. I/O caps are necessary for our test equipment and may not be needed for your application.
Ripple/Noise is shown at Vout = 1V. No load input current is shown at Vout = 0.75V. For Vout = 1V, Vin 32V. For Vout = 0.75V, Vin 24V.
PART NUMBER STRUCTURE
OK
Okami Non-isolated PoL
I - T / 3 - W40 N - C
RoHS Hazardous Substance Compliance C = RoHS-6 (does not claim EU RoHS exemption 7b-lead in solder) On/Off Polarity P = Positive Polarity N = Negative Polarity
Surface Mount
Trimmable Output Voltage Range 0.7525-5.5V
Input Voltage Range 16-40V Maximum Rated Output Current in Amps Note: Some model number combinations may not be available. Contact Murata Power Solutions for availability.
Product Label Because of the small size of these products, the product label contains a character-reduced code to indicate the model number and manufacturing date code. Not all items on the label are always used. Please note that the label differs from the product photograph on page 1. Here is the layout of the label:
Model Number OKI-T/3-W40N-C OKI-T/3-W40P-C Product Code I00103 I01103
The manufacturing date code is four characters:
Mfg. date code XXXXXX YMDX Rev. Product code Revision level
Figure 2. Label Artwork Layout
First character - Last digit of manufacturing year, example 2009 Second character - Month code (1 through 9 and O through D) Third character - Day code (1 through 9 = 1 to 9, 10 = O and 11 through 31 = A through Z) Fourth character - Manufacturing information
The label contains three rows of information: First row - Murata Power Solutions logo Second row - Model number product code (see table) Third row - Manufacturing date code and revision level
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MDC_OKI-T/3-W40 Series.A01_D8 Page 2 of 12
OKI-T/3-W40 Series
Adjustable Output 3-Amp DOSA-SMT DC/DC Converters
MECHANICAL SPECIFICATIONS
TOP VIEW
PIN #1 THIS CORNER (FARSIDE)
11.9 .47
ISOMETRIC VIEW
10.7 .42 REF 5.6 .22 REF PIN #1
NOZZLE PICKUP POINT
20.8 .82
INPUT/OUTPUT CONNECTIONS OKI-T/3 (P78)
SIDE VIEW
8.5 .34
END VIEW
Pin 1 2 3 4 5
Function On/Off Control* +VIN Ground (Common) Trim +VOUT
MTG PLANE
1.59 .063
*The Remote On/Off can be provided with either positive (P suffix) or negative (N suffix) polarity
1.60 .063 TYP
2.29 .090 TYP
BOTTOM VIEW 4 53
1.53 .060
Dimensions are in inches (mm shown for ref. only).
Third Angle Projection
8.63 .340
1.78 .070
Tolerances (unless otherwise specified): .XX 0.02 (0.5) .XXX 0.010 (0.25) Angles 1 Components are shown for reference only.
1 2
.690 4.57 .180 8.63 .340 12.69 .500 17.52 .690 .47 REF .500 .340 .180 .060 REF
0.25 .010
.070 REF
2 3 4
1 5
.340
MATERIAL: SMT PINS: COPPER ALLOY FINISH: (ALL PINS) GOLD (5u"MIN) OVER NICKEL (50u" MIN)
.120 MIN .135 MAX .82 REF
.095 MIN .110 MAX
RECOMMENDED PAD LAYOUT
Figure 2. OKI-T/3 Mechanical Outline
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MDC_OKI-T/3-W40 Series.A01_D8 Page 3 of 12
OKI-T/3-W40 Series
Adjustable Output 3-Amp DOSA-SMT DC/DC Converters
Performance and Functional Specifications
See Note 1
Input Environmental
Input Voltage Range Isolation Start-Up Voltage Undervoltage Shutdown (see Note 15) Overvoltage Shutdown Reflected (Back) Ripple Current (Note 2) Internal Input Filter Type Recommended External Fuse Reverse Polarity Protection Input Current: Full Load Conditions Inrush Transient Shutdown Mode (Off, UV, OT) Output in Short Circuit Low Line (Vin=Vmin) Remote On/Off Control (Note 5) Negative Logic ("N" model suffix) Current Positive Logic ("P" model suffix)
See Ordering Guide and Note 7. Not isolated 15 V 14 V min., 15.5V max. None 20 mA pk-pk Capacitive 1.2A fast blow N/A. See fuse information. See Ordering Guide 0.4 A2Sec. 5 mA 60 mA 1.03A. ON = -0.3V to +1.2V OFF = (Vin -2.5V) to 40V or open 1 mA max. ON = Open pin (internally pulled up) or = (Vin -2.5V) to 40V or open OFF = -0.3V to +1.2V 1 mA max.
Calculated MTBF Telecordia method (4a) Calculated MTBF MIL-HDBK-217N2 method (4b) Operating Temperature Range (Ambient) See derating curves Operating PC Board Temperature Storage Temperature Range Thermal Protection/Shutdown Relative Humidity
TBD TBD -40 to +85 C. with derating (Note 9) -40 to +100 Celsius max., no derating (12) -55 to +125 deg. C. +130 Celsius to 85%/+85 C., non-condensing
Physical
Outline Dimensions Weight Safety Restriction of Hazardous Substances MSL Rating
See Mechanical Specifications 0.072 ounces (2.04 grams) Designed to meet UL/cUL 60950-1, CSAC22.2 No. 60950-1, IEC/EN 60950-1 RoHS-6 (does not claim EU RoHS exemption 7b-lead in solder) 2
Absolute Maximum Ratings
Current
Output
Output Power Minimum Loading Accuracy (50% load, untrimmed) Voltage Output Range (Note 13) Overvoltage Protection (Note 16) Temperature Coefficient Ripple/Noise (20 MHz bandwidth) Line/Load Regulation Efficiency Maximum Capacitive Loading (Note 14) Cap-ESR=0.001 to 0.01 Ohms Cap-ESR >0.01 Ohms Current Limit Inception (Note 6) (98% of Vout setting, after warm up) Short Circuit Mode Short Circuit Current Output Protection Method Short Circuit Duration Prebias Startup
15W max. No minimum load 2 % of Vnominal See Ordering Guide None 0.02% per C of Vout range See Ordering Guide and note 8 See Ordering Guide and note 10 See Ordering Guide 1,000 F 3,000 F (min. cap. load 0 F) 5.5 Amps 0.0 A Hiccup autorecovery upon overload removal. (Note 17) Continuous, no damage (output shorted to ground) Converter will start up if the external output voltage is less than Vnominal.
(1)
Input Voltage (Continuous or transient) On/Off Control Input Reverse Polarity Protection Output Current (Note 7)
0 V.to +40 Volts max. 0 V. min. to +Vin max. See Fuse section Current-limited. Devices can withstand a sustained short circuit without damage. The outputs are not intended to accept appreciable reverse current. Storage Temperature -55 to +125 C. Lead Temperature See soldering specifications Absolute maximums are stress ratings. Exposure of devices to greater than any of 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 nor recommended.
Specification Notes:
Specifications are typical at +25 C, Vin=nominal (+24V.), Vout=nominal (+5V), full load, external caps and natural convection unless otherwise indicated. Extended tests at full power must supply substantial forced airflow. All models are tested and specified with external 1 F paralleled with 10F ceramic/tantalum output capacitors and a 22 F external input capacitor. All capacitors are low ESR types. These capacitors are necessary to accommodate our test equipment and may not be required to achieve specified performance in your applications. However, Murata Power Solutions recommends installation of these capacitors. All models are stable and regulate within spec under no-load conditions. (2) (3) Input Back Ripple Current is tested and specified over a 5 Hz to 20 MHz bandwidth. Input filtering is Cin=2 x 100 F tantalum, Cbus=1000 F electrolytic, Lbus=1 H. Note that 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.
Dynamic Characteristics
(4a) Mean Time Before Failure is calculated using the Telcordia (Belcore) SR-332 Method 1, Case 3, ground fixed conditions, Tpcboard=+25 C, full output load, natural air convection. (4b) Mean Time Before Failure is calculated using the MIL-HDBK-217N2 method, ground benign, +25C., full output load, natural convection.
Dynamic Load Response 125Sec max. to within 2% of final value (50-100 load step, di/dt=2.5A/Sec, 5 Vout, Cout = 1&10F ceramic) Start-Up Time (Vin on or On/Off to Vout regulated) Switching Frequency 8 mSec for Vout=nominal (Vin On) 6 mSec for Vout=nominal (Remote On/Off) 300 KHz
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MDC_OKI-T/3-W40 Series.A01_D8 Page 4 of 12
OKI-T/3-W40 Series
Adjustable Output 3-Amp DOSA-SMT DC/DC Converters
Specification Notes, Cont.:
(5) The On/Off Control Input should use either a switch or an open collector/open drain transistor referenced to -Input Common. A logic gate may also be used by applying appropriate external voltages which do not exceed +Vin. Short circuit shutdown begins when the output voltage degrades approximately 2% from the selected setting. For Vout = 1V, Vin must not exceed 32V. For Vout = 0.75V, Vin must not exceed 24V. Output noise may be further reduced by adding an external filter. At zero output current, the output may contain low frequency components which exceed the ripple specification. The output may be operated indefinitely with no load. All models are fully operational and meet published specifications, including "cold start" at -40 C.
Soldering Guidelines
Murata Power Solutions recommends the specifications below when installing these converters. These specifications vary depending on the solder type. Exceeding these specifications may cause damage to the product. Your production environment may differ therefore please thoroughly review these guidelines with your process engineers.
(6) (7) (8)
(9)
Reflow Solder Operations for surface-mount products (SMT)
(10) Regulation specifications describe the deviation as the line input voltage or output load current is varied from a nominal midpoint value to either extreme. (11) Other input or output voltage ranges will be reviewed under scheduled quantity special order. (12) Maximum PC board temperature is measured with the sensor in the center of the converter. (13) Do not exceed maximum power specifications when adjusting the output trim. (14) The maximum output capacitive loads depend on the the Equivalent Series Resistance (ESR) of the external output capacitor and, to a lesser extent, the distance and series impedance to the load. Larger caps will reduce output noise but may change the transient response. Newer ceramic caps with very low ESR may require lower capacitor values to avoid instability. Thoroughly test your capacitors in the application. Please refer to the Output Capacitive Load Application Note. (15) Do not allow the input voltage to degrade lower than the input undervoltage shutdown voltage at all times. Otherwise, you risk having the converter turn off. The undervoltage shutdown is not latching and will attempt to recover when the input is brought back into normal operating range. (16) The outputs are not intended to sink appreciable reverse current. (17) "Hiccup" overcurrent operation repeatedly attempts to restart the converter with a brief, full-current output. If the overcurrent condition still exists, the restart current will be removed and then tried again. This short current pulse prevents overheating and damaging the converter. Once the fault is removed, the converter immediately recovers normal operation.
For Sn/Ag/Cu based solders: Preheat Temperature Time over Liquidus Maximum Peak Temperature Cooling Rate For Sn/Pb based solders: Preheat Temperature Time over Liquidus Maximum Peak Temperature Cooling Rate Less than 1 C. per second 60 to 75 seconds 235 C. Less than 3 C. per second Less than 1 C. per second 45 to 75 seconds 260 C. Less than 3 C. per second
Recommended Lead-free Solder Reflow Profile
250 Peak Temp. 235-260 C
Temperature (C)
Output Voltage Adustment The output voltage may be adjusted over a limited range by connecting an external trim resistor (Rtrim) between the Trim pin and Ground. The Rtrim resistor must be a 1/10 Watt precision metal film type, 1% accuracy or better with low temperature coefficient, 100 ppm/oC. or better. Mount the resistor close to the converter with very short leads or use a surface mount trim resistor. In the tables below, the calculated resistance is given. Do not exceed the specified limits of the output voltage or the converter's maximum power rating when applying these resistors. Also, avoid high noise at the Trim input. However, to prevent instability, you should never connect any capacitors to Trim.
200
150 Soaking Zone 120 sec max 100 <1.5 C/sec 50 240 sec max
Reflow Zone time above 217 C 45-75 sec
Preheating Zone
0 0 30 60 90 120 150 Time (sec) 180 210 240 270 300
High trace = normal upper limit
Output Voltage Calculated Rtrim (K)
Low trace - normal lower limit
3.3 V. 2.5 V. 2.0 V. 1.8 V. 1.5 V. 1.2 V. 1.0 V. 0.7525 V. Resistor Trim Equation:
3.122 5.009 7.417 9.024 13.047 22.464 41.424 (open)
10500 RTRIM () = _____________ - 1000 VOUT - 0.7525V
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MDC_OKI-T/3-W40 Series.A01_D8 Page 5 of 12
OKI-T/3-W40 Series
Adjustable Output 3-Amp DOSA-SMT DC/DC Converters
APPLICATION NOTES
Input Fusing Certain applications and/or safety agencies may require fuses at the inputs of power conversion components. Fuses should also be used when there is the possibility of sustained input voltage reversal which is not current-limited. For greatest safety, we recommend a fast blow fuse installed in the ungrounded input supply line. The installer must observe all relevant safety standards and regulations. For safety agency approvals, install the converter in compliance with the end-user safety standard, i.e. IEC/EN/UL 60950-1. Input Under-Voltage Shutdown and Start-Up Threshold Under normal start-up conditions, converters will not begin to regulate properly until the ramping-up input voltage exceeds and remains at the Start-Up Threshold Voltage (see Specifications). Once operating, converters will not turn off until the input voltage drops below the Under-Voltage Shutdown Limit. Subsequent restart will not occur until the input voltage rises again above the Start-Up Threshold. This built-in hysteresis prevents any unstable on/off operation at a single input voltage. Users should be aware however of input sources near the Under-Voltage Shutdown whose voltage decays as input current is consumed (such as capacitor inputs), the converter shuts off and then restarts as the external capacitor recharges. Such situations could oscillate. To prevent this, make sure the operating input voltage is well above the UV Shutdown voltage AT ALL TIMES. Start-Up Time Assuming that the output current is set at the rated maximum, the Vin to Vout Start-Up Time (see Specifications) is the time interval between the point when the ramping input voltage crosses the Start-Up Threshold and the fully loaded regulated output voltage enters and remains within its specified accuracy band. Actual measured times will vary with input source impedance, external input capacitance, input voltage slew rate and final value of the input voltage as it appears at the converter. These converters include a soft start circuit to moderate the duty cycle of its PWM controller at power up, thereby limiting the input inrush current. The On/Off Remote Control interval from On command to Vout regulated assumes that the converter already has its input voltage stabilized above the Start-Up Threshold before the On command. The interval is measured from the On command until the output enters and remains within its specified accuracy band. The specification assumes that the output is fully loaded at maximum rated current. Similar conditions apply to the On to Vout regulated specification such as external load capacitance and soft start circuitry. Recommended Input Filtering The user must assure that the input source has low AC impedance to provide dynamic stability and that the input supply has little or no inductive content, including long distributed wiring to a remote power supply. The converter will operate with no additional external capacitance if these conditions are met.
For best performance, we recommend installing a low-ESR capacitor immediately adjacent to the converter's input terminals. The capacitor should be a ceramic type such as the Murata GRM32 series or a polymer type. Initial suggested capacitor values are 10 to 22 F, rated at twice the expected maximum input voltage. Make sure that the input terminals do not go below the undervoltage shutdown voltage at all times. More input bulk capacitance may be added in parallel (either electrolytic or tantalum) if needed. Recommended Output Filtering The converter will achieve its rated output ripple and noise with no additional external capacitor. However, the user may install more external output capacitance to reduce the ripple even further or for improved dynamic response. Again, use low-ESR ceramic (Murata GRM32 series) or polymer capacitors. Initial values of 10 to 47 F may be tried, either single or multiple capacitors in parallel. Mount these close to the converter. Measure the output ripple under your load conditions. Use only as much capacitance as required to achieve your ripple and noise objectives. Excessive capacitance can make step load recovery sluggish or possibly introduce instability. Do not exceed the maximum rated output capacitance listed in the specifications. Input Ripple Current and Output Noise All models in this converter series are tested and specified for input reflected ripple current and output noise using designated external input/output components, circuits and layout as shown in the figures below. The Cbus and Lbus components simulate a typical DC voltage bus. Please note that the values of Cin, Lbus and Cbus will vary according to the specific converter model.
TO OSCILLOSCOPE
CURRENT PROBE +INPUT LBUS CBUS CIN
VIN
+ - + -
-INPUT CIN = 2 x 100F, ESR < 700m @ 100kHz CBUS = 1000F, ESR < 100m @ 100kHz LBUS = 1H
Figure 2: Measuring Input Ripple Current
In figure 3, the two copper strips simulate real-world printed circuit impedances between the power supply and its load. In order to minimize circuit errors and standardize tests between units, scope measurements should be made using BNC connectors or the probe ground should not exceed one halfinch and soldered directly to the test circuit.
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OKI-T/3-W40 Series
Adjustable Output 3-Amp DOSA-SMT DC/DC Converters
CAUTION: If you routinely or accidentally exceed these Derating guidelines, the converter may have an unplanned Over Temperature shut down. Also, these graphs are all collected at slightly above Sea Level altitude. Be sure to reduce the derating for higher density altitude.
SCOPE RLOAD
COPPER STRIP +OUTPUT
C1
C2
-OUTPUT COPPER STRIP
Output Fusing The converter is extensively protected against current, voltage and temperature extremes. However your output application circuit may need additional protection. In the extremely unlikely event of output circuit failure, excessive voltage could be applied to your circuit. Consider using an appropriate fuse in series with the output. Output Current Limiting Current limiting inception is defined as the point at which full power falls below the rated tolerance. See the Performance/Functional Specifications. Note particularly that the output current may briefly rise above its rated value in normal operation as long as the average output power is not exceeded. This enhances reliability and continued operation of your application. If the output current is too high, the converter will enter the short circuit condition. Output Short Circuit Condition When a converter is in current-limit mode, the output voltage will drop as the output current demand increases. If the output voltage drops too low (approximately 98% of nominal output voltage for most models), the magnetically coupled voltage used to develop primary side voltages will also drop, thereby shutting down the PWM controller. Following a time-out period, the PWM will restart, causing the output voltage to begin ramping up to its appropriate value. If the short-circuit condition persists, another shutdown cycle will initiate. This rapid on/off cycling is called "hiccup mode". The hiccup cycling reduces the average output current, thereby preventing excessive internal temperatures and/or component damage. A short circuit can be tolerated indefinitely. The "hiccup" system differs from older latching short circuit systems because you do not have to power down the converter to make it restart. The system will automatically restore operation as soon as the short circuit condition is removed. Remote On/Off Control On the input side, a remote On/Off Control can be ordered with either polarity. Please refer to the Connection Diagram on page 1 for On/Off connections. Positive-polarity models are enabled when the On/Off pin is left open or is pulled high to +Vin with respect to -Vin. Positive-polarity devices are disabled when the On/Off is grounded or brought to within a low voltage (see Specifications) with respect to -Vin. Negative-polarity devices are on (enabled) when the On/Off is left open or brought to within a low voltage (see Specifications) with respect to -Vin. The device is off (disabled) when the On/Off is pulled high (see Specifications) with respect to -Vin. Dynamic control of the On/Off function should be able to sink appropriate signal current when brought low and withstand appropriate voltage when brought high. Be aware too that there is a finite time in milliseconds (see Specifications) between the time of On/Off Control activation and stable, regulated output. This time will vary slightly with output load type and current and input conditions.
C1 = 0.1F CERAMIC C2 = 10F TANTALUM LOAD 2-3 INCHES (51-76mm) FROM MODULE
Figure 3: Measuring Output Ripple and Noise (PARD)
Minimum Output Loading Requirements All models regulate within specification and are stable under no load to full load conditions. Operation under no load might however slightly increase output ripple and noise. Thermal Shutdown To prevent many over temperature problems and damage, these converters include thermal shutdown circuitry. If environmental conditions cause the temperature of the DC/DC's to rise above the Operating Temperature Range up to the shutdown temperature, an on-board electronic temperature sensor will power down the unit. When the temperature decreases below the turn-on threshold, the converter will automatically restart. There is a small amount of hysteresis to prevent rapid on/off cycling. CAUTION: If you operate too close to the thermal limits, the converter may shut down suddenly without warning. Be sure to thoroughly test your application to avoid unplanned thermal shutdown. Temperature Derating Curves The graphs in the next section illustrate typical operation under a variety of conditions. The Derating curves show the maximum continuous ambient air temperature and decreasing maximum output current which is acceptable under increasing forced airflow measured in Linear Feet per Minute ("LFM"). Note that these are AVERAGE measurements. The converter will accept brief increases in current or reduced airflow as long as the average is not exceeded. Note that the temperatures are of the ambient airflow, not the converter itself which is obviously running at higher temperature than the outside air. Also note that "natural convection" is defined as very flow rates which are not using fan-forced airflow. Depending on the application, "natural convection" is usually about 30-65 LFM but is not equal to still air (0 LFM). Murata Power Solutions makes Characterization measurements in a closed cycle wind tunnel with calibrated airflow. We use both thermocouples and an infrared camera system to observe thermal performance. As a practical matter, it is quite difficult to insert an anemometer to precisely measure airflow in most applications. Sometimes it is possible to estimate the effective airflow if you thoroughly understand the enclosure geometry, entry/exit orifice areas and the fan flowrate specifications.
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MDC_OKI-T/3-W40 Series.A01_D8 Page 7 of 12
OKI-T/3-W40 Series
Adjustable Output 3-Amp DOSA-SMT DC/DC Converters
Output Capacitive Load These converters do not require external capacitance added to achieve rated specifications. Users should only consider adding capacitance to reduce switching noise and/or to handle spike current load steps. Install only enough capacitance to achieve noise objectives. Excess external capacitance may cause regulation problems, degraded transient response and possible oscillation or instability.
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MDC_OKI-T/3-W40 Series.A01_D8 Page 8 of 12
OKI-T/3-W40 Series
Adjustable Output 3-Amp DOSA-SMT DC/DC Converters
PERFORMANCE DATA - OKI-T/3-W40
Efficiency vs. Line Voltage and Load Current @ +25C (VOUT = 5V)
95
Maximum Current Temperature Derating at Sea Level (VIN= 24-40V, VOUT = 5V, transverse airflow, mounted on 10" x 10" PCB).
4
90
3
85
Efficiency (%)
80 75 70 65
VIN = 16V VIN = 24V VIN = 40V
Output Current (Amps)
65 LFM 2
1
60 0 0.5 1 1.5 2 2.5 3 3.5
0 30 35 40 45 50 55 60 65 70 75 80 85
Load Curre nt (Amps)
Ambient Temperature (C)
Output Ripple and Noise (Vin=24V, Vout=5V, Iout=3A, Cload=0, ScopeBW=100MHz)
On/Off Enable Startup (Vin=24V, Vout=5V, Iout=3A, Cload=0)
Step Load Transient Response (Vin=24V, Vout=5V, Cload=0, Iout=1.5A to 3A) Trace 2=Vout, 100 mV/div. Trace 4=Iout, 1A/div.
Step Load Transient Response (Vin=24V, Vout=5V, Cload=0, Iout=3A to 1.5A) Trace 2=Vout, 100 mV/div. Trace 4=Iout, 1A/div.
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MDC_OKI-T/3-W40 Series.A01_D8 Page 9 of 12
OKI-T/3-W40 Series
Adjustable Output 3-Amp DOSA-SMT DC/DC Converters
PERFORMANCE DATA - OKI-T/3-W40
Efficiency vs. Line Voltage and Load Current @ +25C (VOUT = 3.3V)
100 95 90 85
Efficiency (%)
80 75 70 65 60 55 50 0 0.5 1 1.5 2 2.5 3 3.5
VIN = 16V VIN = 24V VIN = 40V
Load Curre nt (Amps)
Output Ripple and Noise (Vin=24V, Vout=3.3V, Iout=3A, Cload=0, ScopeBW=100MHz)
Step Load Transient Response (Vin=24V, Vout=3.3V, Cload=0, Iout=1.5A to 3A) Trace 2=Vout, 100 mV/div. Trace 4=Iout, 1A/div.
Step Load Transient Response (Vin=24V, Vout=3.3V, Cload=0, Iout=3A to 1.5A) Trace 2=Vout, 100 mV/div. Trace 4=Iout, 1A/div.
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MDC_OKI-T/3-W40 Series.A01_D8 Page 10 of 12
OKI-T/3-W40 Series
Adjustable Output 3-Amp DOSA-SMT DC/DC Converters
PERFORMANCE DATA - OKI-T/3-W40
Efficiency vs. Line Voltage and Load Current @ +25C (VOUT = 1.5V)
90
80
70
Efficiency (%)
60
VIN = 16V VIN = 24V VIN = 40V
50
40
30 0 0.5 1 1.5 2 2.5 3 3.5
Load Curre nt (Amps)
Output Ripple and Noise (Vin=24V, Vout=1.5V, Iout=3A, Cload=0, ScopeBW=100MHz)
Step Load Transient Response (Vin=24V, Vout=1.5V, Cload=0, Iout=1.5A to 3A) Trace 2=Vout, 100 mV/div. Trace 4=Iout, 1A/div.
Step Load Transient Response (Vin=24V, Vout=1.5V, Cload=0, Iout=3A to 1.5A)Trace 2=Vout, 100 mV/div. Trace 4=Iout, 1A/div.
www.murata-ps.com
05 Nov 2009
email: sales@murata-ps.com
MDC_OKI-T/3-W40 Series.A01_D8 Page 11 of 12
OKI-T/3-W40 Series
Adjustable Output 3-Amp DOSA-SMT DC/DC Converters
PERFORMANCE DATA - OKI-T/3-W40
Efficiency vs. Line Voltage and Load Current @ +25C (VOUT = 1.2V)
80 75 70 65
Efficiency (%)
60 55 50 45 40 35 30 0 0.5 1 1.5 2 2.5 3 3.5
VIN = 16V VIN = 24V VIN = 40V
Load Curre nt (Amps)
Output Ripple and Noise (Vin=24V, Vout=1.2V, Iout=3A, Cload=0, ScopeBW=100MHz)
Step Load Transient Response (Vin=24V, Vout=1.2V, Cload=0, Iout=1.5A to 3A) Trace 2=Vout, 100 mV/div. Trace 4=Iout, 1A/div.
Step Load Transient Response (Vin=24V, Vout=1.2V, Cload=0, Iout=3A to 1.5A) Trace 2=Vout, 100 mV/div. Trace 4=Iout, 1A/div.
Murata Power Solutions, Inc. 11 Cabot Boulevard, Mansfield, MA 02048-1151 U.S.A.
ISO 9001 and 14001 REGISTERED
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. (c) 2009 Murata Power Solutions, Inc.
www.murata-ps.com/locations
05 Nov 2009
email: sales@murata-ps.com
MDC_OKI-T/3-W40 Series.A01_D8 Page 12 of 12

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