UNR-2.5/8-D5-C - Murata Power Solutions

Features

Figure 1. Simpliﬁ ed Schematic

As supply voltages trend lower and load currents increase, centralized power

becomes more impractical. The tight accuracy, low noise and quick transient

response demanded by today's low voltage CPU's, ASIC's and DSP's make power

processing at the point of use the only viable solution. The UNR 18-33W series pro-

vides a complete line of non-isolated DC/DC converters to satisfy this requirement.

With input voltages of 5V (-D5 models) and 12V (-D12 models) these converters

offer standard output voltages of 1.8, 2.5 and 3.3 Volts and up to 10 Amps of output

current in both through-hole and surface-mount 1" x 2" metal cases.

With on/off control and output voltage trim capability as standard features, these

non-isolated converters exploit full synchronous rectiﬁ cation, planar magnetics, and

100% automated assembly to deliver high efﬁ ciencies (to 91%) and low noise at low

cost.

These versatile DC/DC’s are fully line and load regulated. They feature quick

transient response (50µsec), user-optional on/off control (for power sequencing),

and output overcurrent detection and shutdown ("hiccup" technique with auto-recov-

ery). Their impressive guaranteed efﬁ ciencies enable them to deliver fully rated

output power from –40 to +50/55°C (ambient) without supplemental cooling.

If your high current requirements have made the use of inefﬁ cient linear regula-

tors impractical, take a look at one of Murata Power Solutions’ new switching buck

regulators. Their high efﬁ ciency, ease-of-use, long-term reliability, and overall cost

effectiveness will impress you. Safety agency approvals and EMC characterizations

are currently in progress.

OUT

INPUT

RETURN

LOGIC

GROUND

ON/OFF

CONTROL

PWM

CONTROLLER

VOLTAGE

BOOST

REFERENCE &

ERROR AMP

OVERCURRENT

DETECTION

OUTPUT

RETURN

OUT

TRIM

Input ranges of 4.75-5.5V or 10.8-13.6V

Output voltages of 1.8/2.5/3.3V

8 and 10 Amp output current models

VOUT user-trimmable from 1.28V to 3.6V

Non-isolated, full synchronous topology

1" x 2" through-hole or SMT package

Gull-wing leads for SMT package

High efﬁ ciency to 91%; Low noise

200kHz switching; Planar magnetics

–40 to +40/50/60°C ambient operation with

no derating

Remote on/off control; Output overcurrent

detection

IEC950/EN60950/UL1950 approval



➀

➀ -D5 models only.

Typical topology is shown.

UNR18-33W.C01 Page 1 of 9

UNR D5/D12 Series

Single Output, Non-Isolated, 5 or 12VIN to 1.8/2.5/3.3VOUT

8 and 10 Amp DC/DC Converters

www.murata-ps.com

www.murata-ps.com/support

For full details go to

www.murata-ps.com/rohs

OBSOLETE PRODUCT

Click here for more information.

Last time buy: 3 March 2014

MECHANICAL SPECIFICATIONS

2.00

(50.80)

0.10

(2.54)

0.110

(2.79)

0.100

(2.54)

0.300

(7.62)

0.500

(12.70)

TOP VIEW

1.00

(25.40)

0.800

(20.32)

4 EQ. SP. @

0.200 (5.08)

0.060

(1.52)

0.055

(1.40)

0.015

(0.38)

0.110

(2.79)

0.015

(0.38)

0.43

(10.92)

DIMENSIONS ARE IN INCHES (MM)

INSULATED BASE

METAL CASE

Case C18

Performance Speciﬁ cations and Ordering Guide

➀

Output Input

Non-Isolated

Output Conﬁ guration:

U = Unipolar

Nominal Output Voltage:

1.8, 2.5 or 3.3 Volts

Maximum Rated Output

Current in Amps

Input Voltage Range:

D5 = 4.75 to 5.5 Volts (5V nominal)

D12 = 10.8 to 13.6 Volts (12V nominal)

U NR 10

D5 SM

1.8

Packaging:

T = Through-Hole Package

SM = Surface-Mount Package

Package

VOUT IOUT

R/N (mVp-p)

➁

Regulation (Max.) VIN Nom. Range IIN

➃

Efﬁ ciency (Case,

Root Model

➄

(Volts) (Amps) Typ. Max. Line Load

➂

(Volts) (Volts) (mA/mA) Min. Typ. Pinout)

UNR-1.8/10-D5T 1.8 10 70 100 ±0.1% ±0.5% 5 4.75-5.5 150/4190 82% 86% C16A2, P23

UNR-1.8/10-D5SM 1.8 10 40 80 ±0.1% ±0.5% 5 4.75-5.5 150/4190 82% 86% C18, P25

UNR-2.5/10-D5T 2.5 10 75 100 ±0.1% ±0.5% 5 4.75-5.5 150/5620 85% 89% C16A2, P23

UNR-2.5/10-D5SM 2.5 10 75 100 ±0.1% ±0.5% 5 4.75-5.5 150/5620 85% 89% C18, P25

UNR-3.3/8-D5T 3.3 8 40 80 ±0.1% ±0.5% 5 4.75-5.5 100/5470 88% 92% C16A1, P23

UNR-3.3/8-D5SM 3.3 8 40 80 ±0.1% ±0.5% 5 4.75-5.5 100/5470 88% 92% C18, P25

UNR-3.3/8-D12T 3.3 8 40 100 ±0.25% ±0.875% 12 10.8-13.6 50/2420 86% 91% C16A1, P23

UNR-3.3/8-D12SM 3.3 8 40 100 ±0.25% ±0.875% 12 10.8-13.6 50/2420 86% 91% C18, P25

UNR-3.3/10-D5T 3.3 10 40 80 ±0.1% ±0.5% 5 4.75-5.5 150/7250 86% 91% C16A2, P23

UNR-3.3/10-D5SM 3.3 10 50 100 ±0.1% ±0.5% 5 4.75-5.5 150/7250 86% 91% C18, P25

UNR-3.3/10-D12T 3.3 10 70 120 ±0.25% ±0.875% 12 10.8-13.6 90/3090 86% 89% C16C2, P23

UNR-3.3/10-D12SM 3.3 10 70 120 ±0.25% ±0.875% 12 10.8-13.6 90/3090 86% 89% C18, P25

I/O Connections

Pin Function P23 Function P25

1 Logic Ground Logic Ground

2 On/Off Control On/Off Control

3 +Output N.C.

4 Trim N.C.

5 Output Return +Output

6 Input Return Trim

7 +Input Output Return

8 No Pin Input Return

9 No Pin +Input

➀ Typical at TA = +25°C under nominal line voltage and full-load conditions, unless otherwise

noted. All models are tested and speciﬁ ed with an external 22µF output capacitor with a

200mΩ ESR and a 470µF input capacitor with 6Arms ripple-current rating and 20mΩ

ESR. See I/O Filtering and Noise Reduction for more details.

➁ Ripple/Noise (R/N) is tested/speciﬁ ed over a 20MHz bandwidth. Output noise may be further

reduced by installing additional external output caps. See I/O Filtering and Noise Reduction.

➂ These devices have no minimum-load requirements and will regulate under no-load conditions.

➃ Nominal line voltage, no-load/full-load conditions.

➄ These are only partial part numbers, refer to part number structure when ordering.

0.10

(2.54)

METAL CASE

2.00

(50.80)

0.20 MIN

(5.08)

SEE

NOTES

INSULATED BASE

1.800

(45.72)

0.10

(2.54)

0.300

(7.62)

BOTTOM VIEW

DIMENSIONS IN INCHES (MM)

1.00

(25.40)

0.800

(20.32)

4 EQ. SP. @

0.200 (5.08)

0.10

(2.54)

CASE C16A1

CASE HEIGHT: 0.39 (9.91)

PIN DIAMETERS:

PINS 1-7: 0.040 ±0.002 (1.016 ±0.051)

CASE C16A2

CASE HEIGHT: 0.39 (9.91)

PIN DIAMETERS:

PINS 1-2, 4: 0.040 ±0.002 (1.016 ±0.051)

PINS 3, 5-7: 0.062 ±0.002 (1.575 ±0.051)

CASE C16C2

CASE HEIGHT: 0.48 (12.19)

PIN DIAMETERS:

PINS 1-2, 4: 0.040 ±0.002 (1.016 ±0.051)

PINS 3, 5-7: 0.062 ±0.002 (1.575 ±0.051)

Case C16A1, A2,C2

PART NUMBER STRUCTURE

RoHS-6 compliant*

* Contact Murata Power Solutions Technologies (DATEL) for availability.

UNR18-33W.C01 Page 2 of 9

UNR D5/D12 Series

Single Output, Non-Isolated, 5 or 12VIN to 1.8/2.5/3.3VOUT

8 and 10 Amp DC/DC Converters

www.murata-ps.com/support

Return Current Paths

These are non-isolated DC/DC converters. The Input Return, Output Return

and Logic Ground pins are all connected together internally. To the extent

possible, all input and load currents should be returned through the Input

Return and Output Return, respectively (via low-impedance runs). Any con-

trol signals applied to the On/Off Control pin should be referenced to Logic

Ground. The internal trace leading to Logic Ground is not designed to carry

high current. Consequently, devices should never be installed in a manner

that results in high current ﬂ ow through Logic Ground (i.e., the Input/Output

Return pins should never be left open or connected via high-impedance paths).

I/O Filtering and Noise Reduction

All UNR 18-33W Series converters are tested and speciﬁ ed with external

470µF input capacitors (20mΩ ESR, 6Arms ripple-current rating) and

external 22µF output capacitors (200mΩ ESR). External input capacitance is

required and must be rated to handle the input ripple current as follows:

In critical applications, input/output ripple/noise may be further reduced by

installing additional I/O caps.

Performance/Functional Speciﬁ cations

Typical @ TA = +25°C under nominal line voltage and full-load conditions unless noted.

➀

➀ All models are tested and speciﬁ ed with an external 470µF input capacitor with a 20mΩ

ESR and a 6Arms ripple-current rating, as well as a 22µF output capacitor with a 200mΩ ESR.

See I/O Filtering and Noise Reduction for more details. These devices have no minimum-load

requirements and will regulate under no-load conditions. Listed speciﬁ cations apply for both

"T" and "SM" models as appropriate.

➁ See Output Overcurrent Detection for details.

➂ See On/Off Control for details.

➃ See Output Voltage Trimming for details.

➄ For all models, output noise can be further reduced with the installation of additional

external output capacitors. See I/O Filtering and Noise Reduction for details.

➅ See Start-Up Time for details.

➆ See Temperature Derating for details.

Input Voltage:

Continuous:

D5 Models 7 Volts

D12 Models 15 Volts

Transient (100msec) 15 Volts

Input Reverse-Polarity Protection None

Input/Output Overvoltage Protection None

Output Current Current limited. Devices can

withstand a sustained output

short circuit without damage.

Storage Temperature –40 to +105°C

Lead Temperature (Soldering, 10 sec.) +300°C

These are stress ratings. Exposure of devices to 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.

Absolute Maximum Ratings

Input

Input Voltage Range 3.0 to 3.6 Volts (3.3V nominal)

D5 Models 4.75-5.5 Volts (5V nominal)

D12 Models 10.8-13.6 Volts (12V nominal)

Input Current:

Normal Operating Conditions See Ordering Guide

Standby/Off Mode 3.6mA typical

Input Ripple Current:

1.8/2.5V Models 150mAp-p

3.3/8 -D5 Models 100mAp-p

3.3/10 -D5 Models 150mAp-p

3.3/8 -D12 Models 110mAp-p

3/3/10 -D12 Models 250mAp-p

Input Filter Type Capacitive

Overvoltage Protection None

Reverse-Polarity Protection None

On/Off Control: ➂

Functionality TTL high (or open) = on, low = off

Logic Threshold +0.8-2.0 Volts (1.5V typical)

Output

VOUT Accuracy (50% load):

1.8VOUT Models ±2% of VOUT maximum

2.5/3.3VOUT Models ±1% of VOUT maximum

VOUT Trim Range ➃

Trim pin tied to +Output: VOUT = 1.52 Volts or less

Trim pin tied to Output Return VOUT = 3.6 Volts or greater

Temperature Coefﬁ cient ±0.02% per °C

Ripple/Noise (20MHz BW) ➄ See Ordering Guide

Line/Load Regulation See Ordering Guide

Efﬁ ciency See Ordering Guide

Overcurrent Protection: ➁

Technique "Hiccup" with auto-recovery

Overcurrent Detection Point 110-180% of rated current

Average Short Circuit Current:

D5 Models 1 Amp typical, 3 Amps maximum

D12 Models 4 Amp typical, 6 Amps maximum

Dynamic Characteristics

Transient Response (50-100% load):

1.8VOUT Models 100µsec to 3% of ﬁ nal value

1.8/2.5VOUT Models 25µsec to 2.5% of ﬁ nal value

3.3VOUT -D5 Models 50µsec to 2.5% of ﬁ nal value

3.3/8 -D12 Models 50µsec to 1% of ﬁ nal value

3.3/10 -D12 Models 50µsec to 2.5% of ﬁ nal value

Start-Up Time: ➅

V IN to VOUT 25/30msec (1.8/2.5VOUT models)

On/Off to VOUT 25/30msec (1.8/2.5VOUT models)

Switching Frequency 300kHz (±30kHz)

Environmental

Operating Temperature (Ambient): ➆

Without Derating See Derating Curves

With Derating to +100°C (See Derating Curves)

Storage Temperature –40 to +105°C

Physical

Dimensions:

D5 Through-Hole Models 2" x 1" x 0.39" (51 x 25 x 9.9mm)

D5 Surface-Mount Models 2" x 1" x 0.43" (51 x 25 x 10.9mm)

D12 Through-Hole Models 2" x 1" x 0.48" (51 x 25 x 12.2mm)

D12 Surface-Mount Models 2" x 1" x TBD" (51 x 25 x 12.7mm)

Flammability 94V-0

TECHNICAL NOTES

Physical

Shielding 5 sided

Case Connection Input/Output Return

Case Material Corrosion-resistant steel with

non-conductive, epoxy-based, black

enamel ﬁ nish and plastic baseplate

Pin Material RoHS: Gold plate over copper alloy

Non-RoHS: Pure tin on copper alloy with

nickel underplate

IRMS = IOUT VOUT

VIN

VOUT

VIN

(1 – )

√

UNR18-33W.C01 Page 3 of 9

UNR D5/D12 Series

Single Output, Non-Isolated, 5 or 12VIN to 1.8/2.5/3.3VOUT

8 and 10 Amp DC/DC Converters

www.murata-ps.com/support

Figure 2. Driving the On/Off Control Pin

Input Fusing

UNR 18-33W Series DC/DC converters are not internally fused. Certain

applications and or safety agencies may require the installation of fuses

at the inputs of power conversion components. For Murata Power Solu-

tions UNR Series DC/DC converters, you should use either slow-blow or

normal-blow fuses with values no greater than twice the expected input

current at full power. See Ordering Guide.

Input Overvoltage and Reverse-Polarity Protection

UNR 18-33W Series DC/DC converters do not incorporate either input over-

voltage or input reverse-polarity protection. Input voltages in excess of the

listed absolute maximum ratings and input polarity reversals of longer than

"instantaneous" duration can cause permanent damage to these devices.

On/Off Control

The On/Off Control pin may be used for remote on/off operation. UNR 18-

33W Series DC/DC converters are designed so that they are enabled when

the control pin is pulled high or left open (normal mode) and disabled when

the control pin is pulled low (to less than +0.8V relative to Logic Ground). As

shown in Figure 2, D5 models have internal 4.99kΩ pull-up resistors to VIN

(+Input), while D12 models have 12.4kΩ.

Dynamic control of the on/off function is best accomplished with a mechani-

cal relay or open-collector/open-drain drive circuit (optically isolated if appro-

priate). The drive circuit should be able to sink appropriate current when

activated and withstand appropriate voltage when deactivated.

Applying an external voltage to the On/Off Control pin when no input power is

applied to the converter can cause permanent damage to the converter. The

on/off control function, however, is designed such that the converter can be

disabled (control pin pulled low) while input voltage is ramping up and then

"released" once the input has stabilized. The time duration between the point

at which the converter is released and its fully loaded output settles to within

speciﬁ ed accuracy can be found in the Performance/Functional Speciﬁ ca-

tions Table. See Start-Up Time for more details.

Start-Up Time

The VIN to VOUT Start-Up Time is the interval between the time at which a

ramping input voltage crosses the lower limit of the speciﬁ ed input voltage

range (4.75V for D5 models, 10.8V for D12 models) and the fully loaded

output voltage enters and remains within it speciﬁ ed accuracy band. Actual

measured times will vary with heavy capacitive loading.

The On/Off to VOUT Start-Up Time assumes the converter is turned off via the

Remote On/Off Control with the nominal input voltage already applied to the

converter. The speciﬁ cation deﬁ nes the interval between the time at which

the converter is turned on and the fully loaded output voltage enters and

remains within its speciﬁ ed accuracy band. See Typical Performance Curves

for details

Output Overvoltage Protection

UNR 18-33W Series DC/DC converters do not incorporate output overvolt-

age protection. In the extremely rare situation in which the device’s feedback

loop is broken, the output voltage may run to excessively high levels. If it is

absolutely imperative that you protect your load against any and all possible

overvoltage situations, voltage limiting circuitry must be provided external to

the power converter.

+INPUT

LOGIC

GROUND

ON/OFF

CONTROL

RPULL UP

D5 Models 4.99kΩ

D12 Models 12.4kΩ

Output Overcurrent Detection

Overloading the output of a power converter for an extended period of time

will invariably cause internal component temperatures to exceed their maxi-

mum ratings and eventually lead to component failure. High-current-carrying

components such as transformers, FET's and diodes are at the highest risk.

UNR 18-33W Series DC/DC converters incorporate an output overcur-

rent detection and shutdown function that serves to protect both the power

converter and its load.

When the output current of a thermally stabilized converter exceeds the

maximum rating by 40% (typical) to 80% (maximum), the internal overcurrent

detection circuit shuts down the converter by discharging the soft-start circuit

of the pulse width modulator (PWM). In this off state, which is similar to that

achieved by pulling the On/Off Control low, the output voltage quickly drops

as the output capacitors discharge into the load. Since there is no longer any

output current, the overcurrent detection circuit is released, allowing the soft-

start circuit to recharge and the converter to turn on again. If the faulty load

condition persists, the overcurrent detection circuit will again discharge the

soft-start circuit and shut down the converter. This continuous on/off cycling

of the converter is referred to as “hiccup mode.” Once the overload condition

is removed, the converter remains on, and the output voltage is quickly

restored to its regulated value.

The components used to sense the output current have large temperature

coefﬁ cients. Consequently, in a "cold-start" situation, the Overcurrent Detec-

tion Point may temporarily move to 80% to 120% above the rated current

speciﬁ cation. The device quickly heats up, particularly if an overload situation

exists, and restores the normal (40%) Overcurrent Detection Point. The

device will not be damaged by starting up into an output-short-circuit condition.

The overcurrent detection circuitry helps keep internal current levels and

operating temperatures within safe operating limits. Nevertheless, sustained

operation at current levels above the rated output current but below the Over-

current Detection Point may result in permanent damage to the converter.

Output Voltage Trimming

UNR 18-33W devices can be trimmed to any voltage between 1.50V and

3.55V. Trimming is accomplished with either a trimpot or a single ﬁ xed resis-

tor. The trimpot should be connected between +Output and Output Return

with its wiper connected to the Trim pin as shown in Figure 3 below.

UNR18-33W.C01 Page 4 of 9

UNR D5/D12 Series

Single Output, Non-Isolated, 5 or 12VIN to 1.8/2.5/3.3VOUT

8 and 10 Amp DC/DC Converters

www.murata-ps.com/support

LOAD

20kΩ

5-10

Tu r n s

+INPUT

INPUT

RETURN

+OUTPUT

TRIM

OUTPUT

RETURN

Trim

Down

Trim Up

LOAD

+INPUT

INPUT

RETURN

+OUTPUT

TRIM

OUTPUT

RETURN

Figure 4. Trim Connections Using Fixed Resistors

Note: Install either a ﬁ xed trim-up resistor or a ﬁ xed trim-down resistor

depending upon desired output voltage.

A trimpot can be used to determine the value of a single ﬁ xed resistor which

should be connected, as shown in Figure 4, between the Trim pin and

+Output to trim down the output voltage, or between the Trim pin and Output

Return to trim up the output voltage. Fixed resistors should be metal-ﬁ lm

types with absolute TCR’s less than 100ppm/°C to ensure stability.

The equations below can be used as starting points for selecting speciﬁ c

trim-resistor values. Recall that untrimmed devices are guaranteed to be

between ±1% and ±2% accurate, depending on model. See Performance

and Functional Speciﬁ cations.

Figure 3. Trim Connections Using a Trimpot

UNR-1.8/10-D5T

UNR-1.8/10-D5SM

UNR-2.5/10-D5T

UNR-2.5/10-D5SM

–1.74

RT (kΩ) = VO – 1.8

3.14 

–1.74

DOWN

RT (kΩ) = 2.5 – VO

7.5(VO – 1.26)



–1.74

RT (kΩ) = VO – 2.5

9.47 

–1.0

DOWN

RT (kΩ) = 3.3 – VO

7.5(VO – 1.27)



UNR-3.3/8-D5T

UNR-3.3/8-D5SM

UNR-3.3/10-D5T

UNR-3.3/10-D5SM

UNR-3.3/8-D12T

UNR-3.3/8-D12SM

UNR-3.3/10-D12T

UNR-3.3/10-D12SM

–1.0

RT (kΩ) = VO – 3.3

9.5 

–1.0

DOWN

RT (kΩ) = 3.3 – VO

7.5(VO – 1.26)



–1.0

RT (kΩ) = VO – 3.3

9.41

–1.74

DOWN

RT (kΩ) = 1.8 – VO

2.49(VO – 1.26)



Note: Resistor values are in kΩ. Accuracy of adjustment is subject to

tolerances of resistors and factory-adjusted output accuracy.

VO = desired output voltage.

UNR18-33W.C01 Page 5 of 9

UNR D5/D12 Series

Single Output, Non-Isolated, 5 or 12VIN to 1.8/2.5/3.3VOUT

8 and 10 Amp DC/DC Converters

www.murata-ps.com/support

Recommended PC Board Layout

If necessary, a single pc board layout can accommodate both through-hole

and SMT models of the UNR 18-33W Series. Note that on page 2 of this

data sheet, the through-hole package is drawn with a bottom view of its pin

locations, and the surface-mount package is drawn with of top view of its

pin locations. As shown below, the through-hole pin locations, when viewed

from above, fall just inside (on 1.8 inch centers) the SMT pin locations (which

essentially begin on 2.1 inch centers). The table below shows how the pin

functions align.

0.10

(2.54)

0.110

(2.79)

0.100

(2.54)

0.300

(7.62)

0.500

(12.70)

TOP VIEW

1.00

(25.40)

0.800

(20.32)

4 EQ. SP. @

0.200 (5.08)

0.10

(2.54)

1.800

(45.72)

0.10

(2.54)

0.300

(7.62)

TOP VIEW

1.00

(25.40)

0.800

(20.32)

4 EQ. SP. @

0.200 (5.08)

PINS 1-2, 4: 0.040 ±0.002 (1.016 ±0.051)

PINS 3, 5-7: 0.062 ±0.002 (1.575 ±0.051)

Case C16A2

Case C18

+INPUT

+OUTPUT

ON/OFF CONTROL

TRIM

POWER

GROUND

4 No Pin N.C.

3 No Pin N.C.

2 2 On/Off Control

1 1 Logic Ground

9 7 +Input

8 6 Input Return

7 5 Output Return

6 4 Trim

5 3 +Output

SMT Through-Hole

Pin Number Pin Number Pin Function

Figure 5. Recommended Board Layout

SMT Solder Process for SM models

For the surface-mount "SM" models of the UNR Series, the packages’ gull-

wing leads are made of tin-plated (150 microinches) copper. The gull-wing

conﬁ guration, as opposed to “J” leads, was selected to keep the solder joints

out from under the package to minimize both, heat conduction away from the

leads (into the encapsulated package) and shadowing effects.

"SM" modules do not currently withstand the standard solder-reﬂ ow process

with its most common temperature proﬁ les. In order to avoid damage to the

converter a selective solder process (i.e. hot air gun or a hand soldering

method) with the following parameters must therefore be chosen :

Pre-heat phase 30-60°C rise/minute to 150°C maximum.

Lead temperature 300°C for 10 seconds maximum.

As shown in Figure 6, our tests have determined the optimal landing-pad size

to be 160 mils by 130 mils (4 x 3.3 mm).

0.130*

(3.30)

0.015

(0.38)

0.100**

(2.54)

* PAD DIMENSION

** LEAD DIMENSION

0.160*

(4.06)

0.110**

(2.79)

Figure 6 . PC Board Land Pattern

UNR18-33W.C01 Page 6 of 9

UNR D5/D12 Series

Single Output, Non-Isolated, 5 or 12VIN to 1.8/2.5/3.3VOUT

8 and 10 Amp DC/DC Converters

www.murata-ps.com/support

TEMPERATURE DERATING

Output Power (Watts)

Ambient Temperature (˚C)

UNR-1.8/10-D5T/D5SM Output Power vs. Ambient Temperature

–40 0 40 45 50 55 60 65 70 75 80 85 90 95 100

Output Power (Watts)

Ambient Temperature (˚C)

UNR-2.5/10-D5T/D5SM Output Power vs. Ambient Temperature, No Air Flow

27.5

22.5

17.5

12.5

7.5

2.5

–40 0 40 45 50 55 60 65 70 75 80 85 90 95 100

Output Power (Watts)

Ambient Temperature (˚C)

UNR-3.3/10-D12T/D12SM Output Power vs. Ambient Temperature, No Air Flow

–40 0 40 45 50 55 60 65 70 75 80 85 90 95 100

Output Power (Watts)

Ambient Temperature (˚C)

UNR-3.3/10-D5T/D5SM Output Power vs. Ambient Temperature, No Air Flow

–40 0 40 45 50 55 60 65 70 75 80 85 90 95 100

Output Power (Watts)

Ambient Temperature (˚C)

UNR-3.3/8-D12T/D12SM Output Power vs. Ambient Temperature, No Air Flow

–40 0 40 45 50 55 60 65 70 75 80 85 90 95 100

Output Power (Watts)

Ambient Temperature (˚C)

UNR-3.3/8-D5T/D5SM Output Power vs. Ambient Temperature, No Air Flow

27.5

22.5

17.5

12.5

7.5

2.5

–40 0 40 45 50 55 60 65 70 75 80 85 90 95 100

UNR18-33W.C01 Page 7 of 9

UNR D5/D12 Series

Single Output, Non-Isolated, 5 or 12VIN to 1.8/2.5/3.3VOUT

8 and 10 Amp DC/DC Converters

www.murata-ps.com/support

UNR-1.8/10-D5T/D5SM Efficiency vs. Line/Load

12345678910

Load Current (Amps)

Efficiency (%)

= 4.75V

= 5.5V

= 5V

UNR-2.5/10-D5T/D5SM Efficiency vs. Line/Load

12345678910

Load Current (Amps)

Efficiency (%)

= 4.75V

= 5V

= 5.5V

UNR-3.3/10-D5T/D5SM Efficiency vs. Line/Load

12345678910

Load Current (Amps)

Efficiency (%)

= 4.75V

= 5V

= 5.5V

UNR-3.3/8-D12T/D12SM Efficiency vs. Line/Load

123 4 567 8

Load Current (Amps)

Efficiency (%)

= 10.4V

= 12V

= 13.6V

UNR-3.3/8-D5T/D5SM Efficiency vs. Line/Load

123 4 567 8

Load Current (Amps)

Efficiency (%)

= 4.75V

= 5V

= 5.5V

EFFICIENCY VS. LINE/LOAD

UNR18-33W.C01 Page 8 of 9

UNR D5/D12 Series

Single Output, Non-Isolated, 5 or 12VIN to 1.8/2.5/3.3VOUT

8 and 10 Amp DC/DC Converters

www.murata-ps.com/support

TYPICAL PERFORMANCE CURVES

VIN to VOUT Start-Up Time

On/Off Control to VOUT Start-Up Time

D5 Models, Start-up from VIN

(Full load, using specified output capacitor.)

VOUT

1V/div

VIN

2V/div

10msec/div

D5 Models, Start-up from Enable

(Full load, using specified output capacitor.)

VOUT

1V/div

ENABLE

2V/div

10msec/div

D12 Models, Start-up from VIN

(Full load, using specified output capacitor.)

VOUT

1V/div

VIN

5V/div

10msec/div

D12 Models, Start-up from Enable

(Full load, using specified output capacitor.)

VOUT

1V/div

ENABLE

5V/div

10msec/div

UNR18-33W.C01 Page 9 of 9

UNR D5/D12 Series

Single Output, Non-Isolated, 5 or 12VIN to 1.8/2.5/3.3VOUT

8 and 10 Amp DC/DC Converters

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/

Mouser Electronics

Authorized Distributor

Click to View Pricing, Inventory, Delivery & Lifecycle Information:

Murata:

UNR-2.5/8-D5-C