OKY-T/3-W5N-C - MURATA POWER SOLUTIONS

The OKY-T/3 and -T/5 series are miniature non-

isolated Point-of-Load (POL) switch mode DC/DC

power converters for embedded applications. The

module is fully compatible with Distributed-power

Open Standards Alliance (DOSA) industry-standard

speciﬁ cations (www.dosapower.com). Applications

include powering CPU’s, datacom/telecom systems,

programmable logic and mixed voltage systems.

The wide input range is 2.4 to 5.5 Volts DC. Two

maximum output currents are offered, 3 Amps (T/3

models) or 5 Amps (T/5 models). Based on ﬁ xed-

frequency synchronous buck converter switching

topology, the high power conversion efﬁ cient 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, over-current and over

temperature protections.

These units are designed to meet all standard

UL/EN/IEC 60950-1 safety and FCC EMI/RFI

emissions certiﬁ cations and RoHS-6 hazardous

substance compliance.

PRODUCT OVERVIEW

Connection Diagram

Figure 1. OKY-T/3, -T/5

Note: Murata Power Solutions strongly recommends an external input fuse, F1.

See speciﬁ cations.

External

Power

Source

F1 On/Off

Control

CommonCommon

Open = On

Closed = Off

+Vin +Vout

Trim

Controller

Reference and

Error Ampliﬁer

t4XJUDIJOH

t'JMUFST

t$VSSFOU4FOTF

(Positive

On/Off)

FEATURES

■ Non-isolated SMT POL DC/DC power module

■ 2.4-5.5Vdc input voltage range

■ Programmable output voltage from 0.7525-3.63Vdc

■ 3 Amp (T/3) or 5 Amp (T/5) output current models

■ Drives 1000 µF ceramic capacitive loads

■ High power conversion efﬁ ciency at 96%

■ Outstanding thermal derating performance

■ Over temperature and over current protection

■ On/Off control

■ UL/EN/IEC 60950-1 safety

■ Industry-standard (DOSA) surface-mount package

■ RoHS-6 hazardous substance compliance

Typical unit

Contents Page

Description, Connection Diagram, Photograph 1

Ordering Guide, Model Numbering, Product Label 2

Mechanical Speciﬁ cations, Input/Output Pinout 3

Detailed Electrical Speciﬁ cations 4

Output Voltage Adjustment, Soldering Guidelines 5

Technical Notes 6

OKY-T/3-W5 Performance Data and Oscillograms 9

OKY-T/5-W5 Performance Data and Oscillograms 13

Tape and Reel Information 19

Typical uni

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 1 of 19

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For full details go to

www.murata-ps.com/rohs

PART NUMBER STRUCTURE

➀ Dimensions are in inches (mm).

➁ These are partial model numbers. Please refer to the part number structure for complete ordering part numbers.

➂ All specifications are at nominal line voltage, Vout=nominal (3.3V) and full load, +25 ˚C. unless otherwise noted.

Output capacitors are 1 µF ceramic and 10 µF electrolytic in parallel. Input cap is 22 µF. See detailed specifications.

I/O caps are necessary for our test equipment and may not be needed for your application.

Vin must be 0.5V or higher than Vout.

Ripple and Noise is shown at Vout=1V.

ORDERING GUIDE

Root Model ➁

Output Input

Efﬁ ciency

Package

VOUT

(Volts)

IOUT

(Amps

max)

Power

(Watts)

R/N (mVp-p)➄Regulation (Max.)➂

VIN Nom.

(Volts)

Range

(Volts) 

IIN,

no load

(mA)

IIN,

full load

(Amps) Case C72 ➀PinoutMax. Line Load Min. Typ.

OKY-T/3-W5N-C 0.7525-3.63 3 9.9 20 ±0.2% ±1.5% 5 2.4-5.5 45 2.1 92% 94.4% 0.47 x 0.82 x 0.28

(11.9 x 20.8 x 7.0) P78

OKY-T/3-W5P-C 0.7525-3.63 3 9.9 20 ±0.2% ±1.5% 5 2.4-5.5 45 2.1 92% 94.4% 0.47 x 0.82 x 0.28

(11.9 x 20.8 x 7.0) P78

OKY-T/5-W5N-C 0.7525-3.63 5 16.5 20 ±0.2% ±1% 5 2.4-5.5 35 3.5 92% 96% 0.47 x 0.82 x 0.28

(11.9 x 20.8 x 7.0) P78

OKY-T/5-W5P-C 0.7525-3.63 5 16.5 20 ±0.2% ±1% 5 2.4-5.5 35 3.5 92% 96% 0.47 x 0.82 x 0.28

(11.9 x 20.8 x 7.0) P78

Performance Speciﬁ cations Summaryand Ordering Guide

Okami Non-isolated PoL

Maximum Rated Output

Current in Amps

Surface Mount

Trimmable Output

Voltage Range

0.75-3.63V

Input Voltage Range

2.4-5.5V

On/Off Polarity

P = Positive Polarity

N = Negative Polarity

OK Y -/ W5-T 3 C-

RoHS Hazardous

Substance Compliance

C = RoHS-6 (does not claim EU RoHS exemption

7b–lead in solder)

Note: Some model number combinations

may not be available. Contact Murata

Power Solutions for availability.

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 2 of 19

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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 dif-

fers from the product photograph on page 1. Here is the layout of the label:

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

The manufacturing date code is four characters:

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

Figure 2. Label Artwork Layout

Y01003 Product code

Mfg.

date

code

Revision levelYMDX Rev.

Model Number Product Code

OKY-T/3-W5N-C Y00003

OKY-T/3-W5P-C Y01003

OKY-T/5-W5N-C Y00005

OKY-T/5-W5P-C Y01005

MECHANICAL SPECIFICATIONS

0.010

17.52

0.690

4.57

0.180

8.63

0.340

12.69

0.500

0.340

0.25

8.63 0.07

1.8

5.64

REF

0.222

0.420

REF

10.67

BOTTOM VIEW

4 5

TYP

0.090

2.29

1.59

0.063

TYP

0.06

1.5

END VIEW

MATERIAL:

SMT PINS: COPPER ALLOY

FINISH: (ALL PINS)

GOLD (5u"MIN) OVER NICKEL (50u" MIN)

ISOMETRIC

VIEW

PIN #1

RECOMMENDED PAD LAYOUT

TOP VIEW

PIN #1 THIS

POINT

PICKUP

CORNER (FARSIDE)

NOZZLE

0.47

11.9

0.82

20.8

SIDE VIEW

[17.52]

0.690

[11.9]

0.47

REF

[1.52]

0.060

REF

[1.52]

0.06

[4.57]

0.180

[8.63]

0.340

[8.63] 0.340

[12.69]

0.500

[1.8]

0.070

REF

[20.8] 0.82 REF

[3.05] 0.120 MIN

[3.43] 0.135 MAX

[2.41] 0.095 MIN

[2.79] 0.110 MAX

0.28

7.0

0.063

1.59

MTG PLANE

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 3 of 19

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INPUT/OUTPUT CONNECTIONS

OKY-T/3, -T/5

Pin Function

1 On/Off Control*

2+VIN

3 Ground (Common)

4 Trim

5+VOUT

*The Remote On/Off can be provided with

either positive (P sufﬁ x) or negative (N

sufﬁ x) polarity

Third Angle Projection

Dimensions are in inches (mm shown for ref. only).

Components are shown for reference only.

Tolerances (unless otherwise speciﬁed):

.XX ± 0.02 (0.5)

.XXX ± 0.010 (0.25)

Angles ± 1˚

Performance and Functional Speciﬁ cations

See Note 1

Input

Input Voltage Range See Ordering Guide and Note 7.

Isolation Not isolated

Start-Up Voltage 2.05 V

Undervoltage Shutdown (see Note 15) 1.90 V

Overvoltage Shutdown None

Reﬂ ected (Back) Ripple Current (Note 2) 20 mA pk-pk

Internal Input Filter Type Capacitive

Recommended External Fuse 6A

Reverse Polarity Protection N/A. See fuse information.

Input Current:

Full Load Conditions See Ordering Guide

Inrush Transient 0.4 A2Sec.

Shutdown Mode (Off, UV, OT) 5 mA

Output in Short Circuit 60 mA

Low Line (Vin=Vmin) 2.66 A. (OKY-T/3-W5)

4.41 A. (OKY-T/5-W5)

Remote On/Off Control (Note 5)

Negative Logic (“N” model sufﬁ x) ON = Open pin or ground to +0.4V. max.

OFF = +1.5V min. to +Vin

Current 1 mA max.

Positive Logic (“P” model sufﬁ x) ON = Open pin (internally pulled up) or

+7.8Vdc to +Vin max.

OFF = Ground pin to +0.4V. max.

Current 1 mA max.

Output

Output Power 9.9W max. (OKY-T/3), 16.5W max. (OKY-T/5)

Output Voltage Range See Ordering Guide

Minimum Loading No minimum load

Accuracy (50% load, untrimmed) ±2 % of Vnominal

Voltage Output Range (Note 13) See Ordering Guide

Overvoltage Protection (Note 16) None

Temperature Coefﬁ cient ±0.02% per °C of Vout range

Ripple/Noise (20 MHz bandwidth) See Ordering Guide and note 8

Line/Load Regulation See Ordering Guide and note 10

Efﬁ ciency See Ordering Guide

Maximum Capacitive Loading (Note 14)

Cap-ESR=0.001 to 0.01 Ohms 1,000 F

Cap-ESR >0.01 Ohms 3,000 F

Current Limit Inception (Note 6)

(98% of Vout setting, after warm up) 5 Amps

Short Circuit Mode

Short Circuit Current Output 2 A

Protection Method Hiccup autorecovery upon overload

removal. (Note 17)

Short Circuit Duration Continuous, no damage

(output shorted to ground)

Prebias Startup Converter will start up if the external

output voltage is less than Vnominal.

Dynamic Characteristics

Dynamic Load Response 90Sec max. to within ±2% of ﬁ nal value

(50-100-50% load step, di/dt=2.5A/Sec)

Start-Up Time 8 mSec for Vout=nominal (Vin On)

(Vin on or On/Off to Vout regulated) 6 mSec for Vout=nominal (Remote On/Off)

Switching Frequency 300 KHz

Environmental

Calculated MTBF

Telecordia method (4a) OKY-T/3-W5N-C: 10,961,200 hours

OKY-T/3-W5P-C: 10,830,600 hours

OKY-T/5-W5N-C: 9,893,917 hours

OKY-T/5-W5P-C: 9,765,731 hours

Calculated MTBF

MIL-HDBK-217N2 method (4b) OKY-T/3-W5N-C: 8,398,873 hours

OKY-T/3-W5P-C: 8,228,758 hours

OKY-T/5-W5N-C: 8,338,304 hours

OKY-T/5-W5P-C: 8,170,610 hours

Operating Temperature Range (Ambient, vertical mount)

See derating curves -40 to +85 ˚C. with derating (Note 9)

Operating PC Board Temperature -40 to +100 ˚Celsius max., no derating (12)

Storage Temperature Range -55 to +125 deg. C.

Thermal Protection/Shutdown +130 ˚Celsius

Relative Humidity to 85%/+85 ˚C., non-condensing

Physical

Outline Dimensions See Mechanical Speciﬁ cations

Weight 0.1 ounces (2.8 grams)

Electromagnetic Interference Designed to meet FCC part 15, class B,

EN55022 and CISPR22 class B conducted

and radiated (may need external ﬁ lter)

Safety Designed to meet UL/cUL 60950-1, CSA-

C22.2 No. 60950-1, IEC/EN 60950-1

Restriction of Hazardous Substances RoHS-6 (does not claim EU RoHS exemption

7b–lead in solder)

MSL Rating 2

Absolute Maximum Ratings

Input Voltage (Continuous or transient) 0 V.to +5.8 Volts max.

On/Off Control 0 V. min. to +Vin max.

Input Reverse Polarity Protection See Fuse section

Output Current (Note 7) 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 speciﬁ cations

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 Speciﬁ cations

Table is not implied nor recommended.

Speciﬁ cation Notes:

(1) Speciﬁ cations are typical at +25 °C, Vin=nominal (+5V.), Vout=nominal (+3.3V), full load, external caps and

natural convection unless otherwise indicated. Extended tests at full power must supply substantial forced

airﬂ ow.

All models are tested and speciﬁ ed with external 1 F paralleled with 10F 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 speciﬁ ed 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) Input Back Ripple Current is tested and speciﬁ ed over a 5 Hz to 20 MHz bandwidth. Input ﬁ ltering is Cin=2 x

100 F tantalum, Cbus=1000 F electrolytic, Lbus=1 H.

(3) Note that Maximum Power Derating curves indicate an average current at nominal input voltage. At higher

temperatures and/or lower airﬂ ow, the DC/DC converter will tolerate brief full current outputs if the total

RMS current over time does not exceed the Derating curve.

(4a) Mean Time Before Failure is calculated using the Telcordia (Belcore) SR-332 Method 1, Case 3, ground ﬁ xed

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, +25ºC., full

output load, natural convection.

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 4 of 19

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Speciﬁ cation 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.

(6) Short circuit shutdown begins when the output voltage degrades approximately 2% from the selected

setting.

(7) For W5 models, the Input Voltage must exceed the Output Voltage at all times by 0.5 Volts or greater.

(8) Output noise may be further reduced by adding an external ﬁ lter. At zero output current, the output may

contain low frequency components which exceed the ripple speciﬁ cation. The output may be operated

indeﬁ nitely with no load.

(9) All models are fully operational and meet published speciﬁ cations, including “cold start” at –40˚ C.

(10) Regulation speciﬁ cations 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 speciﬁ cations 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.

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 ﬁ lm type, ±1% accuracy or

better with low temperature coefﬁ cient, ±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

speciﬁ ed 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 capaci-

tors to Trim.

RTRIM () = _____________ – 5110

VOUT – 0.7525V

21070

OKY-T/3-W5, -T/5-W5

Output Voltage Calculated Rtrim (KΩ)

3.3 V. 3.160

2.5 V. 6.947

2.0 V. 11.780

1.8 V. 15.004

1.5 V. 23.077

1.2 V. 41.973

1.0 V. 80.021

0.7525 V. ∞ (open)

Resistor Trim Equation, W5 models:

Soldering Guidelines

Murata Power Solutions recommends the speciﬁ cations below when installing these

converters. These speciﬁ cations vary depending on the solder type. Exceeding these

speciﬁ cations may cause damage to the product. Your production environment

may differ therefore please thoroughly review these guidelines with your process

engineers.

Recommended Lead-free Solder Reﬂ ow Proﬁ le

High trace = normal upper limit

Low trace - normal lower limit

100

150

200

250

0 30 60 90 120 150 180 210 240 270 300

Time (sec)

Temperature (°C)

Preheating Zone

240 sec max

Soaking Zone

120 sec max

Reﬂow Zone

time above 217° C

45-75 sec

Peak Temp.

235-260° C

<1.5° C/sec High trace = normal upper limit

Low trace = normal lower limit

Reflow Solder Operations for surface-mount products (SMT)

For Sn/Ag/Cu based solders:

Preheat Temperature Less than 1 ºC. per second

Time over Liquidus 45 to 75 seconds

Maximum Peak Temperature 260 ºC.

Cooling Rate Less than 3 ºC. per second

For Sn/Pb based solders:

Preheat Temperature Less than 1 ºC. per second

Time over Liquidus 60 to 75 seconds

Maximum Peak Temperature 235 ºC.

Cooling Rate Less than 3 ºC. per second

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 5 of 19

www.murata-ps.com/support

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. We

recommend a time delay fuse installed in the ungrounded input supply line

with a value which is approximately twice the maximum line current, calcu-

lated at the lowest input voltage.

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 Speciﬁ cations). 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 opera-

tion 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 Speciﬁ cations) 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 speciﬁ ed accuracy band.

Actual measured times will vary with input source impedance, external input

capacitance, input voltage slew rate and ﬁ nal 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 speciﬁ ed accuracy

band. The speciﬁ cation assumes that the output is fully loaded at maximum

rated current. Similar conditions apply to the On to Vout regulated speciﬁ cation

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.

TECHNCIAL NOTES 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 µF, rated at twice the expected maxi-

mum 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 capaci-

tance 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 µF 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 capaci-

tance listed in the speciﬁ cations.

Input Ripple Current and Output Noise

All models in this converter series are tested and speciﬁ ed for input reﬂ ected

ripple current and output noise using designated external input/output compo-

nents, circuits and layout as shown in the ﬁ gures below. In the ﬁ gure 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 speciﬁ c

converter model.

In ﬁ gure 4, the two copper strips simulate real-world printed circuit imped-

ances 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 half-

inch and soldered directly to the test circuit.

BUS

= 2 x 100µF, ESR < 700mΩ @ 100kHz

BUS

= 1000µF, ESR < 100mΩ @ 100kHz

BUS

= 1µH

+INPUT

-INPUT

CURRENT

PROBE

OSCILLOSCOPE

–

Figure 3. Measuring Input Ripple Current

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 6 of 19

www.murata-ps.com/support

Minimum Output Loading Requirements

All models regulate within speciﬁ cation 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 applica-

tion to avoid unplanned thermal shutdown.

Temperature Derating Curves

The graphs in this data sheet 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 airﬂ ow measured in Linear Feet per Minute (“LFM”).

Note that these are AVERAGE measurements. The converter will accept brief

increases in current or reduced airﬂ ow as long as the average is not exceeded.

Note that the temperatures are of the ambient airﬂ ow, not the converter

itself which is obviously running at higher temperature than the outside air.

Also note that very low ﬂ ow rates (below about 25 LFM) are similar to “natural

convection”, that is, not using fan-forced airﬂ ow.

Murata Power Solutions makes Characterization measurements in a closed

cycle wind tunnel with calibrated airﬂ ow. We use both thermocouples and an

infrared camera system to observe thermal performance.

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.

Output Fusing

The converter is extensively protected against current, voltage and temperature

extremes. However your output application circuit may need additional protec-

tion. 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 deﬁ ned as the point at which full power falls below

the rated tolerance. See the Performance/Functional Speciﬁ cations. Note par-

ticularly that the output current may brieﬂ y 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 (approxi-

mately 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 indeﬁ nitely.

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 condi-

tion 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 Speciﬁ ca-

tions) with respect to –Vin.

Negative polarity devices are on (enabled) when the On/Off pin is left open

or brought to within a low voltage (see Speciﬁ cations) with respect to –Vin. The

device is off (disabled) when the On/Off is pulled high (see Speciﬁ cations) with

respect to –Vin.

C1 = 0.1µF CERAMIC

C2 = 10µF TANTALUM

LOAD 2-3 INCHES (51-76mm) FROM MODULE

C2 R

LOAD

COPPER STRIP

SCOPE

+OUTPUT

-OUTPUT

Figure 4. Measuring Output Ripple and Noise (PARD)

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 7 of 19

www.murata-ps.com/support

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 ﬁ nite time in milliseconds (see

Speciﬁ cations) 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.

Output Capacitive Load

These converters do not require external capacitance added to achieve rated

speciﬁ cations. 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 oscilla-

tion or instability.

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 8 of 19

www.murata-ps.com/support

OKY-T/3-W5 PERFORMANCE DATA (Vout = 1.2V)

OKY-T/3-W5 Efﬁ ciency vs. Line Voltage and Load Current @ 25°C (VOUT = 1.2V)

100

0 0.5 1 1.5 2 2.5 3 3.5

VIN = 5.5V

VIN = 5V

VIN = 2.4V

Efﬁciency (%)

Load Current (Amps)

OKY-T/3-W5 Maximum Current Temperature Derating at Sea Level

(VIN = 3.3 to 5V, VOUT = 0.75 to 3.3V, VIN>VOUT + 0.5V)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

20 25 30 35 40 45 50 55 60 65 70 75 80 85 90

Natural convection

Output Current (Amps)

Ambient Temperature (ºC)

On/Off Enable Startup (Vin=5.5V, Vout=1.2V, Iout=3A, Cload=0)

Trace 4=Enable, Trace2=Vout

Step Load Transient Response (Vin=5V, 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=5V, Vout=1.2V, Cload=0, Iout=3A to 1.5A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 1A/div.

Output Ripple and Noise (Vin=5V, Vout=1.2V, Iout=3A, Cload=0, ScopeBW=100MHz)

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 9 of 19

www.murata-ps.com/support

OKY-T/3-W5 PERFORMANCE DATA (Vout = 1.5V)

OKY-T/3-W5 Efﬁ ciency vs. Line Voltage and Load Current @ 25°C (VOUT = 1.5V)

100

0 0.5 1 1.5 2 2.5 3 3.5

VIN = 5.5V

VIN = 5V

VIN = 2.4V

Efﬁciency (%)

Load Current (Amps)

OKY-T/3-W5 Maximum Current Temperature Derating at Sea Level

(VIN = 3.3 to 5V, VOUT = 0.75 to 3.3V, VIN>VOUT + 0.5V)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

20 25 30 35 40 45 50 55 60 65 70 75 80 85 90

Natural convection

Output Current (Amps)

Ambient Temperature (ºC)

On/Off Enable Startup (Vin=5.5V, Vout=1.5V, Iout=3A, Cload=0)

Trace 4=Enable, Trace2=Vout

Step Load Transient Response (Vin=5V, 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=5V, Vout=1.2V, Cload=0, Iout=3A to 1.5A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 1A/div.

Output Ripple and Noise (Vin=5V, Vout=1.5V, Iout=3A, Cload=0, ScopeBW=100MHz)

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 10 of 19

www.murata-ps.com/support

OKY-T/3-W5 PERFORMANCE DATA (Vout = 1.8V)

OKY-T/3-W5 Efﬁ ciency vs. Line Voltage and Load Current @ 25°C (VOUT = 1.8V)

100

0 0.5 1 1.5 2 2.5 3 3.5

VIN = 5.5V

VIN = 5V

VIN = 2.4V

Efﬁciency (%)

Load Current (Amps)

OKY-T/3-W5 Maximum Current Temperature Derating at Sea Level

(VIN = 3.3 to 5V, VOUT = 0.75 to 3.3V, VIN>VOUT + 0.5V)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

20 25 30 35 40 45 50 55 60 65 70 75 80 85 90

Natural convection

Output Current (Amps)

Ambient Temperature (ºC)

On/Off Enable Startup (Vin=5.5V, Vout=1.8V, Iout=3A, Cload=0)

Trace 4=Enable, Trace2=Vout

Step Load Transient Response (Vin=5V, Vout=1.8V, Cload=0, Iout=1.5A to 3A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 1A/div.

Step Load Transient Response (Vin=5V, Vout=1.8V, Cload=0, Iout=3A to 1.5A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 1A/div.

Output Ripple and Noise (Vin=5V, Vout=1.8V, Iout=3A, Cload=0, ScopeBW=100MHz)

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 11 of 19

www.murata-ps.com/support

OKY-T/3-W5 PERFORMANCE DATA (Vout = 2.5V)

OKY-T/3-W5 Efﬁ ciency vs. Line Voltage and Load Current @ 25°C (VOUT = 2.5V)

100

0 0.5 1 1.5 2 2.5 3 3.5

VIN = 5.5V

VIN = 5V

VIN = 3V

Efﬁciency (%)

Load Current (Amps)

OKY-T/3-W5 Maximum Current Temperature Derating at Sea Level

(VIN = 3.3 to 5V, VOUT = 0.75 to 3.3V, VIN>VOUT + 0.5V)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

20 25 30 35 40 45 50 55 60 65 70 75 80 85 90

Natural convection

Output Current (Amps)

Ambient Temperature (ºC)

On/Off Enable Startup (Vin=5.5V, Vout=2.5V, Iout=3A, Cload=0)

Trace 4=Enable, Trace2=Vout

Step Load Transient Response (Vin=5V, Vout=2.5V, Cload=0, Iout=1.5A to 3A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 1A/div.

Step Load Transient Response (Vin=5V, Vout=2.5V, Cload=0, Iout=3A to 1.5A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 1A/div.

Output Ripple and Noise (Vin=5V, Vout=2.5V, Iout=3A, Cload=0, ScopeBW=100MHz)

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 12 of 19

www.murata-ps.com/support

OKY-T/3-W5 PERFORMANCE DATA (Vout = 3.3V)

OKY-T/5-W5 PERFORMANCE DATA (Vout = 1V)

On/Off Enable Startup (Vin=5.5V, Vout=3.3V, Iout=3A, Cload=0)

Trace 4=Enable, Trace2=Vout

Step Load Transient Response (Vin=5V, 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=5V, Vout=3.3V, Cload=0, Iout=3A to 1.5A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 1A/div.

Output Ripple and Noise (Vin=5V, Vout=3.3V, Iout=3A, Cload=0, ScopeBW=100MHz)

OKY-T/5-W5 Efﬁ ciency vs. Line Voltage and Load Current @ 25°C (VOUT = 1V)

0123456

100

= 5.5V

= 5V

= 2.4V

Efﬁciency (%)

Load Current (Amps)

OKY-T/5-W5 Maximum Current Temperature Derating at Sea Level

(VIN = 3.3 to 5V, VOUT = 0.75 to 3.3V, VIN>VOUT + 0.5V)

1.0

2.0

3.0

4.0

5.0

20 25 30 35 40 45 50 55 60 65 70 75 80 85 90

Natural convection

Output Current (Amps)

Ambient Temperature (ºC)

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 13 of 19

www.murata-ps.com/support

OKY-T/5-W5 PERFORMANCE DATA (Vout = 1.2V)

OKY-T/5-W5 Efﬁ ciency vs. Line Voltage and Load Current @ 25°C (VOUT = 1.2V)

0123456

100

VIN = 5.5V

VIN = 5V

VIN = 2.4V

Efﬁciency (%)

Load Current (Amps)

OKY-T/5-W5 Maximum Current Temperature Derating at Sea Level

(VIN = 3.3 to 5V, VOUT = 0.75 to 3.3V, VIN>VOUT + 0.5V)

1.0

2.0

3.0

4.0

5.0

20 25 30 35 40 45 50 55 60 65 70 75 80 85 90

Natural convection

Output Current (Amps)

Ambient Temperature (ºC)

On/Off Enable Startup (Vin=5.5V, Vout=1.2V, Iout=5A, Cload=0)

Trace 4=Enable, Trace2=Vout

Step Load Transient Response (Vin=5V, Vout=1.2V, Cload=0, Iout=2.5A to 5A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 2A/div.

Step Load Transient Response (Vin=5V, Vout=1.2V, Cload=0, Iout=5A to 2.5A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 2A/div.

Output Ripple and Noise (Vin=5V, Vout=1.2V, Iout=5A, Cload=0, ScopeBW=100MHz)

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 14 of 19

www.murata-ps.com/support

OKY-T/5-W5 PERFORMANCE DATA (Vout = 1.5V)

OKY-T/5-W5 Maximum Current Temperature Derating at Sea Level

(VIN = 3.3 to 5V, VOUT = 0.75 to 3.3V, VIN>VOUT + 0.5V)

1.0

2.0

3.0

4.0

5.0

20 25 30 35 40 45 50 55 60 65 70 75 80 85 90

Natural convection

Output Current (Amps)

Ambient Temperature (ºC)

OKY-T/5-W5 Efﬁ ciency vs. Line Voltage and Load Current @ 25°C (VOUT = 1.5V)

0123456

100

VIN = 5.5V

VIN = 5V

VIN = 2.4V

Efﬁciency (%)

Load Current (Amps)

On/Off Enable Startup (Vin=5.5V, Vout=1.5V, Iout=5A, Cload=0)

Trace 4=Enable, Trace2=Vout

Step Load Transient Response (Vin=5V, Vout=1.5V, Cload=0, Iout=2.5A to 5A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 2A/div.

Step Load Transient Response (Vin=5V, Vout=1.5V, Cload=0, Iout=5A to 2.5A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 2A/div.

Output Ripple and Noise (Vin=5V, Vout=1.5V, Iout=5A, Cload=0, ScopeBW=100MHz)

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 15 of 19

www.murata-ps.com/support

OKY-T/5-W5 PERFORMANCE DATA (Vout = 1.8V)

OKY-T/5-W5 Maximum Current Temperature Derating at Sea Level

(VIN = 3.3 to 5V, VOUT = 0.75 to 3.3V, VIN>VOUT + 0.5V)

1.0

2.0

3.0

4.0

5.0

20 25 30 35 40 45 50 55 60 65 70 75 80 85 90

Natural convection

Output Current (Amps)

Ambient Temperature (ºC)

OKY-T/5-W5 Efﬁ ciency vs. Line Voltage and Load Current @ 25°C (VOUT = 1.8V)

0123456

100

VIN = 5.5V

VIN = 5V

VIN = 2.4V

Efﬁciency (%)

Load Current (Amps)

On/Off Enable Startup (Vin=5.5V, Vout=1.8V, Iout=5A, Cload=0)

Trace 4=Enable, Trace2=Vout

Step Load Transient Response (Vin=5V, Vout=1.8V, Cload=0, Iout=2.5A to 5A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 2A/div.

Step Load Transient Response (Vin=5V, Vout=1.8V, Cload=0, Iout=5A to 2.5A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 2A/div.

Output Ripple and Noise (Vin=5V, Vout=1.8V, Iout=5A, Cload=0, ScopeBW=100MHz)

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 16 of 19

www.murata-ps.com/support

OKY-T/5-W5 PERFORMANCE DATA (Vout = 2.5V)

OKY-T/5-W5 Maximum Current Temperature Derating at Sea Level

(VIN = 3.3 to 5V, VOUT = 0.75 to 3.3V, VIN>VOUT + 0.5V)

1.0

2.0

3.0

4.0

5.0

20 25 30 35 40 45 50 55 60 65 70 75 80 85 90

Natural convection

Output Current (Amps)

Ambient Temperature (ºC)

OKY-T/5-W5 Efﬁ ciency vs. Line Voltage and Load Current @ 25°C (VOUT = 2.5V)

100

0123456

VIN = 5.5V

VIN = 5V

VIN = 3V

Efﬁciency (%)

Load Current (Amps)

On/Off Enable Startup (Vin=5.5V, Vout=2.5V, Iout=5A, Cload=0)

Trace 4=Enable, Trace2=Vout

Step Load Transient Response (Vin=5V, Vout=2.5V, Cload=0, Iout=2.5A to 5A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 2A/div.

Step Load Transient Response (Vin=5V, Vout=2.5V, Cload=0, Iout=5A to 2.5A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 2A/div.

Output Ripple and Noise (Vin=5V, Vout=2.5V, Iout=5A, Cload=0, ScopeBW=100MHz)

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 17 of 19

www.murata-ps.com/support

OKY-T/5-W5 PERFORMANCE DATA (Vout = 3.3V)

OKY-T/5-W5 Efﬁ ciency vs. Line Voltage and Load Current @ 25°C (VOUT = 3.3V)

100

0123456

VIN = 5.5V

VIN = 5V

VIN = 3.8V

Efﬁciency (%)

Load Current (Amps)

OKY-T/5-W5 Maximum Current Temperature Derating at Sea Level

(VIN = 3.3 to 5V, VOUT = 0.75 to 3.3V, VIN>VOUT + 0.5V)

1.0

2.0

3.0

4.0

5.0

20 25 30 35 40 45 50 55 60 65 70 75 80 85 90

Natural convection

Output Current (Amps)

Ambient Temperature (ºC)

On/Off Enable Startup (Vin=5.5V, Vout=3.3V, Iout=5A, Cload=0)

Trace 4=Enable, Trace2=Vout

Step Load Transient Response (Vin=5V, Vout=3.3V, Cload=0, Iout=2.5A to 5A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 2A/div.

Step Load Transient Response (Vin=5V, Vout=3.3V, Cload=0, Iout=5A to 2.5A)

Trace 2=Vout, 100 mV/div. Trace 4=Iout, 2A/div.

Output Ripple and Noise (Vin=5V, Vout=3.3V, Iout=5A, Cload=0, ScopeBW=100MHz)

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 18 of 19

www.murata-ps.com/support

Third Angle Projection

Dimensions are in inches (mm shown for ref. only).

Components are shown for reference only.

Tolerances (unless otherwise speciﬁed):

.XX ± 0.02 (0.5)

.XXX ± 0.010 (0.25)

Angles ± 1˚

(P/U)

2.33

40.40

1.591

2.00

0.079

22.25

(P/U)

0.876

0.092 0.630

16.00

4.00

(CORE)

101.6

REF

5.64

0.222

0.420

10.67

1.73

REF

44.0

TOP COVER TAPE

FEED (UNWIND)

DIRECTION -------

ROUND

HOLES

OBLONG

HOLES

PICK & PLACE PICKUP (P/U) REEL INFORMATION

(400 UNITS PER REEL)

1.732

44.00

0.157

4.00

13.00

330.2

.512

13.00

PIN #1 THIS

CORNER

(FARSIDE)

PICKUP NOZZLE

LOCATION

(3-6mm)

0.47

REF

11.9

0.82

REF

20.8

0.270

6.86

TAPE AND REEL INFORMATION

OKY T/3, T/5-W5 Series

Adjustable Output 3 and 5-Amp DOSA-SMT PoLs

MDC_OKY-T/3,T/5-W5 Series.A12 Page 19 of 19

www.murata-ps.com/support

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. Speciﬁ cations are subject to change without

Murata Power Solutions, Inc.

11 Cabot Boulevard, Mansﬁ eld, 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/