UCH-5/20-D24PB-Y - Murata Power Solutions

Figure 1. Simpliﬁ ed Schematic

–VIN

(1)

+VIN

(4)

CASE

(2)

REMOTE*

ON/OFF

CONTROL

(3)

PMW

CONTROLLER

OPTO

ISOLATION

REFERENCE &

ERROR MAP

SWITCH

CONTROL

INPUT UNDERVOLTAGE, INPUT

OVERVOLTAGE, AND OUTPUT

OVERVOLTAGE COMPARATORS

+VOUT

(5)

–VOUT

(9)

VOUT

TRIM

(7)

+SENSE

(6)

–SENSE

(8)

Typical topology is shown.

*Can be ordered with positive (standard)

or negative (optional) polarity.

Typical Unit

FEATURES



Standard “half-brick” conﬁ guration



Certiﬁ ed to UL-60950-1, CSA-C22.2 No.

60950-1, IEC\EN 60950-1, 2nd edition

(some models pending)



Fully isolated, 2250Vdc guaranteed



Output voltages: 1.8 – 15 Volts



VIN range: 36-75V or 18-36V



Full 50-150 Watt output power



Reliable SMT-on-pcb construction

 Input under and output overvoltage shutdown



Output current limiting and short-circuit

protection



On/off, VOUT trim and sense functions



Modiﬁ cations and customs for OEMs



RoHS-6 construction/attach

The high efﬁ ciency, low noise and long-term

reliability that deﬁ nes DATEL DC/DC Converters

now comes to you in the standard “half-brick” con-

ﬁ guration (2.3˝ x 2.4˝ x 0.40˝). Our new UCH Series

is certiﬁ ed to UL/EN60950-1 safety requirements

(some models pending), including each European

country’s deviations. All models have BASIC insula-

tion; guarantee 2250Vdc (in to out) isolation; and

because they are designed with Class B thermal

insulation, satisfy all safety requirements over their

full operating temperatures. Construction/attach

meets stringent RoHS-6 speciﬁ cations.

UCH Models are designed for demanding tele-

com, datacom and networking applications. Their

“semi-synchronous-rectiﬁ er” design achieves

impressive efﬁ ciencies. Output voltages are

1.8to15 Volts. The input voltage range is 36 to 75

or 18 to 36 Volts. All models meet the Low Voltage

Directive (LVD).

For high reliability and affordability, DATEL

utilizes high-speed automatic assembly to

construct the UCH’s proven SMT-on-pcb designs.

An optional baseplate offers full output power at

maximum temperature.

UCH’s feature input ﬁ lters, input undervoltage

and overvoltage lockout, output current limiting,

short-circuit protection, and thermal shutdown.

Additionally, all devices have output trim capability

and an on/off control pin that can be ordered with

either polarity.

PRODUCT OVERVIEW

Typical Uni

FEATURES

he hig

reliabili

now co

ﬁ gurati

is certi

ﬁ

(some

countr

tion; g

becaus

insulati

REG.-Nr. C457

(some models pending

certiﬁ cation)

For full details go to

www.murata-ps.com/rohs

www.murata-ps.com

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Single Output UCH Models

Isolated, “Half-Brick”

1.8−15V Output DC/DC Converters

MDC_UCH Models.A23 Page 1 of 18

Output

Conﬁ guration:

Unipolar Single Output

Maximum Rated Output:

Current in Amps

Half-brick package

Nominal Output Voltage

Input Voltage Range:

D24 = 18-36 Volts

D48 = 36-75 Volts

U CH -/ D48-30 N5 B -

PART NUMBER STRUCTURE

H C

On/Off Control Polarity

P = Positive polarity (standard for D24, optional for D48)

N = Negative polarity (standard for D48, optional for D24)

Optional Baseplate

Blank = No Baseplate, standard

B = Baseplate installed, optional quantity order

Optional Conformal Coating

Blank = No coating, standard

H = Coating added, optional special order

RoHS Hazardous Materials Compliance

C = RoHS-6 (does not claim EU RoHS exemption 7b–lead in solder), standard

Y = RoHS-5 (with lead), optional, special order

Note:

Some model number combinations

may not be available. Please contact

Murata Power Solutions.

PERFORMANCE SPECIFICATIONS SUMMARY AND ORDERING GUIDE ➀

Root Family ➀

Output Input

Efﬁ ciency

Package C61

Case

Pinout

VOUT

(Volts)

IOUT

(Amps)

Power

(Watts)

R/N (mVp-p) ➁Regulation (Max.)

VIN Nom.

(Volts)

Range

(Volts)

IIN,

no load

(mA)

IIN, full

load

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

inches

(mm)

UCH-1.8/40-D48N-C 1.8 40 72 50 100 ±0.125% ±0.25% 48 36-75 50 1.72 85% 87%

2.4×2.28×0.40

(61×57.9×10.2) P17

UCH-2.5/40-D48N-C 2.5 40 100

100 ±0.1% ±0.2% 48 36-75 50 2.34 87.5%

89%

UCH-3.3/10-D24P-C

3.3

10 33

±0.2%

±0.25%

24 18-36

100

1.54

87%

UCH-3.3/10-D48N-C 10 33 ±0.2% 48 36-75 0.77

UCH-3.3/15-D48N-C 15 49.5 ±0.125% 48 36-75 1.16

UCH-3.3/35-D24P-C 35 115.5 ±0.125% 24 18-36 5.41

UCH-3.3/30-D48N-C 30 99 ±0.125% 48 36-75 2.29 89% 90%

UCH-5/10-D48N-C

10 50 60 150 ±0.125% 48 36-75 1.17 85.5% 89%

UCH-5/20-D24P-C 20 100 50 100 ±0.125% 24 18-36 4.6 89% 90.5%

UCH-5/30-D48N-C 30 150 60 ±0.125%

48 36-75

3.43 91%

UCH-12/4.2-D48N-C 12 4.2 50.4 80 150 ±0.125%

1.16 87.5% 90.5%

UCH-12/12.5-D48N-C 12 12.5 150 50 150 ±0.125% 3.37 89% 92.6%

UCH-15/6.7-D48N-C ➂15 6.7 100.5 70 2.28 90% 92%

➀ Please refer to the full model number structure for additional ordering part numbers and options.

➁ All speciﬁ cations are at nominal line voltage and full load, +25 °C. unless otherwise noted. See detailed speciﬁ cations. Output capacitors are 1 μF ceramic in parallel with 10 μF electrolytic . Input cap is 22

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

➂ Pending UL and VDE certification.

Pin Length Option

Blank = Standard pin length, 0.180 inches (4.6mm)

L1 = 0.110 inches (2.79mm)*

L2 = 0.145 inches (3.68mm)*

*Special quantity order is required;

no sample quantities available.

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Single Output UCH Models

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MDC_UCH Models.A23 Page 2 of 18

FUNCTIONAL SPECIFICATIONS ➀

UCH-1.8/40-D48 UCH-2.5/40-D48 UCH-3.3/10-D24 UCH-3.3/10-D48 UCH-3.3/15-D48 UCH-3.3/35-D24 UCH-3.3/30-D48

Input

Input voltage range See ordering guide

Start-up threshold, Volts 34 34 16 34 34 16 34

Undervoltage

shutdown, V 32 31 15 31 31 15 31

Overvoltage shutdown none

Reﬂ ected (back) ripple cur-

rent, mA pk-pk 10 20 10 15 15 15 10

Input Current

Full load conditions See ordering guide.

Inrush transient, A2sec 0.05

Output short circuit, mA 50

Low line (VIN = min.), Amps 2.30 1.54 2.06 1.03 1.54 7.21 3.09

Standby mode, mA

(Off, UV, OT shutdown) 210 8

Internal input ﬁ lter type Pi L-C

External recommended fast

blow fuse, Amps 10 3 5 3 3 12.5 7.5

Reverse polarity

protection None. Install external fuse.

Remote On/Off Control

Positive logic

(P model sufﬁ x)

OFF = Ground pin to +1V max.

ON = Open or +3.5 to +13.5V max

Negative logic

(N model sufﬁ x)

OFF = Open or +2.5V to +15V max.

ON = –0.1V to +0.8V max

Current, mA 1

Output

Voltage output range See ordering guide.

Voltage output accuracy ±1% of VNOM (50% load)

Adjustment range –10 to +10% of VNOM.

Temperature coefﬁ cient

over oper. temp. range ±0.02% of VOUT range per °C

Minimum loading No minimum loading.

Remote sense

compensation +10%.

Ripple/noise

(20 MHz bandwidth) See ordering guide.

Line/Load regulation See ordering guide.

Efﬁ ciency See ordering guide.

Maximum capacitive loading,

Low ESR <0.02 max.,

resistive load, F

10,000 max.

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Single Output UCH Models

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1.8−15V Output DC/DC Converters

MDC_UCH Models.A23 Page 3 of 18

UCH-5/10-D48 UCH-5/20-D24 UCH-5/30-D48 UCH-12/4.2-D48 UCH-12/12.5-D48 UCH-15/6.7-D48

Input

Input voltage range See ordering guide.

Start-up threshold, Volts 34 16 35 35 35 35

Undervoltage

shutdown, V 33 15 34 33.5 33.5 33

Overvoltage shutdown none

Reﬂ ected (back) ripple cur-

rent, mA pk-pk 15 20 15 20 20 20

Input Current

Full load conditions See ordering guide.

Inrush transient, A2sec 0.05

Output short circuit, mA 50

Low line (VIN = min.), Amps 1.54 6.17 4.63 1.51 4.47 3.06

Standby mode, mA

(Off, UV, OT shutdown) 4104 1

Internal input ﬁ lter type Pi L-C Pi L-C

External recommended fast

blow fuse, Amps 10 10 7.5 10 7.5

Reverse polarity

protection None. Install external fuse.

Remote On/Off Control

Positive logic

(P model sufﬁ x)

OFF = Ground pin to +1V max.

ON = Open or +3.5 to +15V max

Negative logic

(N model sufﬁ x)

OFF = Open or +2.5V to +15V max.

ON = –0.1V to +0.8V max

Current, mA 1

Output

Voltage output range See ordering guide.

Voltage output accuracy ±1% of VNOM.

Adjustment range –10 to +10% of VNOM.

Temperature coefﬁ cient

over oper. Temp. range ±0.02% of VOUT range per °C

Minimum loading No minimum loading.

Remote sense

compensation +10%.

Ripple/noise

(20 MHz bandwidth) See ordering guide.

Line/Load regulation See ordering guide.

Efﬁ ciency See ordering guide.

Maximum capacitive loading,

Low ESR <0.02 max.,

resistive load, F

10,000 10,000 max. 20,000 max. 5000 10,000 1,000

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MDC_UCH Models.A23 Page 4 of 18

UCH-1.8/40-D48 UCH-2.5/40-D48 UCH-3.3/10-D24 UCH-3.3/10-D48 UCH-3.3/15-D48 UCH-3.3/35-D24 UCH-3.3/30-D48

Isolation Voltage

Input to Output, Volts min. 2250

Input to baseplate, Volts min. 1500

Baseplate to output, Volts min. 1500

Isolation resistance, MΩ 100

Isolation capacitance, pF 1000

Isolation safety rating Basic insulation

Current limit inception (98% of

VOUT, after warmup), Amps 59 max. 49 15 15 19 40 35

Short circuit protection method Current limiting, hiccup autorestart. Remove overload for recovery.

Short circuit current, Amps 5

Short circuit duration Output may be shorted continuously to ground (no damage).

Overvoltage protection, Volts

(via magnetic feedback) 2.7 max. 3.75 max. 4.95 V max 4.62 max. 4.95 max.

Prebiased Startup Starts if external voltage is less than VNOM.

Dynamic characteristics

Dynamic load response

(50-75-50% load step)

100 µSec to ±1%

of ﬁ nal value

100 µSec to ±1%

of ﬁ nal value

200 µSec to ±1%

of ﬁ nal value

200 µSec to ±1%

of ﬁ nal value

200 µSec to ±1%

of ﬁ nal value

200 µSec to ±1%

of ﬁ nal value

200 µSec to ±1%

of ﬁ nal value

Start-up time

VIN to VOUT regulated, mSec 10 max.

Remote On/Off to VOUT

regulated, mSec 10 max.

Switching frequency, KHz 360 420 ± 40 330 ± 40

Environmental

Calculated MTBF 1.6M hrs. TBD 1.8M hrs. TBD

Operating ambient temperature

range, °C (with derating) −40 to +85 (See Derating Curves)

Operating PC board

temperature, °C −40 to +110

Storage temperature range, °C −55 to +125

Thermal protection/shutdown, °C +115 +115 +120

Relative humidity To +85°C/85%, non-condensing

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 ca-

tions may cause damage to the product. Your production environment may differ; therefore please thoroughly review these guidelines with your process engineers.

Wave Solder Operations for through-hole mounted products (THMT)

For Sn/Ag/Cu based solders: For Sn/Pb based solders:

Maximum Preheat Temperature 115° C. Maximum Preheat Temperature 105° C.

Maximum Pot Temperature 270° C. Maximum Pot Temperature 250° C.

Maximum Solder Dwell Time 7 seconds Maximum Solder Dwell Time 6 seconds

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Single Output UCH Models

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MDC_UCH Models.A23 Page 5 of 18

UCH-5/10-D48 UCH-5/20-D24 UCH-5/30-D48 UCH-12/4.2-D48 UCH-12/12.5-D48 UCH-15/6.7-D48

Isolation Voltage

Input to Output, Volts min. 2250

Input to baseplate, Volts min. 1500

Baseplate to output, Volts min. 1500

Isolation resistance, MΩ 100

Isolation capacitance, pF 1000

Isolation safety rating Basic insulation

Miscellaneous

Current limit inception (98% of VOUT,

after warmup), Amps 13 26 35 5.4 14.5 7.4

Short circuit protection method Current limiting, hiccup autorestart. Remove overload for recovery.

Short circuit current, Amps 5

Short circuit duration Output may be shorted continuously to ground (no damage).

Overvoltage protection, Volts

(via magnetic feedback) 7.75 max. 7.5 max. 7.5 18 max. 16.8 max. 17.5

Prebiased Startup Starts if external voltage is less than VNOM.

Dynamic characteristics

Dynamic load response

(50-75-50% load step)

200 µSec to ±1%

of ﬁ nal value

200 µSec to ±1%

of ﬁ nal value

200 µSec to ±1%

of ﬁ nal value

250 µSec to ±1%

of ﬁ nal value

250 µSec to ±1%

of ﬁ nal value

250 µSec to ±1%

of ﬁ nal value

Start-up time

VIN to VOUT regulated, mSec 10 max.

Remote On/Off to VOUT

regulated, mSec 10 max.

Switching frequency, KHz 300 ± 30 330 ± 40 300 ± 30 335 ± 35 335 ± 35 350 ± 40

Environmental

Calculated MTBF 1.6M hours TBD 1.9M hours 1.6M hours TBD

Operating ambient temperature

range, °C (with derating) −40 to +85 (See Derating Curves)

Operating PC board

temperature, °C −40 to +110

Storage temperature range, °C −55 to +125

Thermal protection/shutdown, °C +120 +115

Relative humidity To +85°C/85%, non-condensing

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Single Output UCH Models

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MDC_UCH Models.A23 Page 6 of 18

UCH-1.8/40-D48 UCH-2.5/40-D48 UCH-3.3/10-D24 UCH-3.3/10-D48 UCH-3.3/15-D48 UCH-3.3/35-D24 UCH-3.3/30-D48

Physical

Outline dimensions See mechanical specs.

Baseplate material Aluminum

Pin material Gold plated copper alloy with nickel underplate

Pin diameter 0.04/0.08 inches (1.016/2.032 mm)

Weight, ounces 1.68 2

Weight, grams 47 60

Electromagnetic

interference

(conducted and

radiated)

(external ﬁ lter

required)

Certiﬁ ed to EN55022/CISPR22

Flammability UL94V-0

Safety Certiﬁ ed to UL 60950-1, CSA C22.2 No.60950-1, IEC/EN 60950-1, 2nd edition (some models pending).

UCH-5/10-D48 UCH-5/20-D24 UCH-5/30-D48 UCH-12/4.2-D48 UCH-12/12.5-D48 UCH-15/6.7-D48

Physical

Outline dimensions See mechanical specs.

Baseplate material Aluminum

Pin material Gold plated copper alloy with nickel underplate

Pin diameter 0.04/0.08 inches (1.016/2.032 mm)

Weight, ounces 2 1.73

Weight, grams 60 49

Electromagnetic

interference

(conducted and

radiated)

(external ﬁ lter

required)

Certiﬁ ed to EN55022/CISPR22

Flammability UL94V-0

Safety Certiﬁ ed to UL 60950-1, CSA C22.2 No.60950-1, IEC/EN 60950-1, 2nd edition (some models pending).

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Single Output UCH Models

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MDC_UCH Models.A23 Page 7 of 18

Speciﬁ cation Notes:

(1) All models are tested and speciﬁ ed with external 1 μF paralleled with 10 μF output capacitors

and no 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. All models are stable and regulate within spec under no-load conditions.

All speciﬁ cations are typical unless noted. General conditions for Speciﬁ cations are +25°C,

Vin=nominal, Vout=nominal, full load. Adequate airﬂ ow must be supplied for extended testing under

power.

(2) Input Back Ripple Current is tested and speciﬁ ed over a 5 Hz to 20 MHz bandwidth. Input ﬁ ltering

is Cin=33 μF, 100V, Cbus=220 μF, 100V, Lbus=12 μH.

(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. All Derating curves are pre-

sented at sea level altitude. Be aware of reduced power dissipation with increasing altitude.

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

ground ﬁ xed conditions, Tpcboard=+25°C, full load, natural air convection.

(5) The On/Off Control is normally selected by a switch or an open collector or open drain transistor.

But it may also be driven with external logic or by applying appropriate external voltages which are

referenced to Input Common and comply with the On/Off voltage speciﬁ cations.

(6) Output current limiting begins when the output voltage degrades approximately 2% from the

selected setting.

(7) The outputs are not intended to sink appreciable reverse current.

(8) Output noise may be further reduced by adding an external ﬁ lter. Logic circuits with low power

voltages may have a small voltage margin between logic ZERO and logic ONE, requiring noise sup-

pression. Use only as much output ﬁ ltering as needed to achieve your noise requirements. Excessive

output capacitance can retard transient response or possibly cause instability. Low ESR ceramic

capacitors may degrade dynamic performance. Be sure to thoroughly test your system under full load

with all components installed.

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

At full power, the package temperature of all on-board components must not exceed +128°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) The output overvoltage protection is automatic recovery. The overvoltage may occur either from

internal failure or from an external forcing voltage as in a shared power system.

(12) Output current limit and short circuit protection is non-latching. When the overcurrent fault is

removed, the converter will immediately recover. After an output overcurrent or short circuit, “hiccup”

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 immedi-

ately resumes normal operation.

(13) Do not exceed maximum power speciﬁ cations when adjusting the output trim.

(14) 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.

(15) If reverse polarity is accidentally applied to the input, to ensure reverse input protection with full

output load, always connect an external input fuse in series with the +Vin input. Use approximately

twice the full input current rating with nominal input voltage.

(16) Output accuracy is dependent on user-supplied trim resistors. To achieve high accuracy, use ±1%

or better tolerance metal-ﬁ lm resistors mounted close to the converter.

(17) Normally, the Sense lines are connected at the remote load to compensate for IR voltage drops

in the power wiring and to improve dynamic response. If Sense is not used, each Sense pin should be

connected at the converter to its respective Vout pin.

CAUTION: This product is not internally fused. To comply with safety agency certiﬁ cations and to

avoid injury to personnel or equipment, the user must connect an external fast-blow fuse to the input

terminals.

Input Voltage:

D24 Models - Volts, max. continuous 0-36 VDC

Volts, transient, 100 mSec 50 VDC

D48 Models - Volts, max. continuous 0-75 VDC

Volts, transient, 100 mSec 100 VDC

On/Off Control -0.7 V. min to +15V max.

Input Reverse-Polarity Protection None. Install external fuse.

Output Overvoltage Vout nom. +20% max.

Output Current Current-limited. Devices can

withstand sustained short

circuit without damage. The

outputs are not intended to

accept appreciable reverse

current.

Overtemperature Protection Device includes electronic

overtemperature shutdown

protection under normal

operation.

Storage Temperature -55 to +125° C

Lead Temperature See soldering speciﬁ cations

These are stress ratings. Exposure of devices to greater than any of these conditions may

adversely affect long-term reliability. Proper operation under conditions other than those

listed in the Performance/Functional Speciﬁ cations Table is not implied.

Absolute Maximum Ratings

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Single Output UCH Models

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1.8−15V Output DC/DC Converters

MDC_UCH Models.A23 Page 8 of 18

Output Current (Amps)

Ambient Temperature (°C)

400 lfm

200 lfm

300 lfm

100 lfm

30 40 50 60 70 80

UCH-2.5/40-D48 Maximum Current Temperature Derating (at sea level)

No baseplate, VIN = 48V, transverse airflow

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

400 lfm

200 lfm

300 lfm

100 lfm

UCH-1.8/40-D48 Maximum Current Temperature Derating (at sea level)

No baseplate, VIN = 48V, airflow is from VIN to VOUT

Output Current (Amps)

Ambient Temperature (°C)

= 48V

= 75V

Efficiency (%)

Power Dissipation (Watts)

Load Current (Amps)

= 36V

63 9 12 15 18 21 24 27

Power Dissipation

= 48V)

UCH-2.5/40-D48 Efficiency and Power Dissipation

vs Line Voltage and Load Current @25˚C

4 8 12 16 20 24 28 32 36 40

UCH-1.8/40-D48 Efficiency and Power Dissipation

vs Line Voltage and Load Current @25˚C

= 48V

= 75V

Efficiency (%)

Power Dissipation (Watts)

Load Current (Amps)

= 36V

Power Dissipation

= 48V)

1.1

2.2

3.3

4.4

5.5

6.6

7.7

8.8

9.9

12.1

= 48V

= 36V

Efficiency (%)

Load Current (Amps)

= 75V

435

678910

Power Dissipation

= 48V)

UCH-3.3/10-D48 Maximum Current Temperature Derating

vs Line Voltage and Load Current @25˚C

Power Dissipation (Watts)

3.2

3.4

3.6

3.8

2.8

3.0

= 24V

= 18V

Efficiency (%)

Load Current (Amps)

= 36V

435678910

Power Dissipation

= 24V)

UCH-3.3/10-D24 Efficiency and Power Dissipation

vs Line Voltage and Load Current @25˚C

Power Dissipation (Watts)

TYPICAL PERFORMANCE DATA

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MDC_UCH Models.A23 Page 9 of 18

Output Current (Amps)

Ambient Temperature (°C)

400 lfm

200 lfm

300 lfm

100 lfm

30 40 50 60 70

UCH-3.3/35-D24 Maximum Current Temperature Derating (at sea level)

No baseplate, VIN = 24V, transverse airflow

= 24V

= 18V

Efficiency (%)

Load Current (Amps)

= 36V

63 9 12 15 18 21 27 3024 33

Power Dissipation

= 24V)

UCH-3.3/35-D24 Efficiency and Power Dissipation

vs Line Voltage and Load Current @25˚C

Power Dissipation (Watts)

Output Current (Amps)

Ambient Temperature (°C)

200 lfm

300 lfm

100 lfm

30 40 50 60 8070

UCH-3.3/30-D48 Maximum Current Temperature Derating (at sea level)

No baseplate, VIN = 48V, transverse airflow

Efficiency (%)

Load Current (Amps)

63 9 12 15 18 21 27 3024

Power Dissipation

= 48V)

= 36V

= 48V

= 75V

UCH-3.3/30-D48 Efficiency and Power Dissipation

vs Line Voltage and Load Current @25˚C

Power Dissipation (Watts)

Efficiency (%)

Load Current (Amps)

= 75V

43 5 6 7 8 9 11 1210 13 1514

Power Dissipation

= 48V)

= 48V

= 36V

UCH-3.3/15-D48 Efficiency and Power Dissipation

vs Line Voltage and Load Current @25˚C

Power Dissipation (Watts)

TYPICAL PERFORMANCE DATA

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Single Output UCH Models

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MDC_UCH Models.A23 Page 10 of 18

Output Current (Amps)

Ambient Temperature (°C)

400 lfm200 lfm

30 40 50 60 70 80

300 lfm

100 lfm

UCH-5/20-D24 Maximum Current Temperature Derating (at sea level)

No baseplate, VIN = 24V, transverse airflow

= 24V

= 18V

Efficiency (%)

Load Current (Amps)

= 36V

63 9 12 15 18

Power Dissipation

= 24V)

UCH-5/20-D24 Efficiency and Power Dissipation

vs Line Voltage and Load Current @25˚C

Power Dissipation (Watts)

Output Current (Amps)

Ambient Temperature (°C)

400 lfm200 lfm

30 40 50 60 70 80

300 lfm

100 lfm

UCH-5/30-D48 Maximum Current Temperature Derating (at sea level)

No baseplate, VIN = 48V, transverse airflow

Efficiency (%)

Load Current (Amps)

63 9 12 1815 24 2721 30

= 48V

= 75V

= 36V Power Dissipation

= 48V)

UCH-5/30-D48 Efficiency and Power Dissipation

vs Line Voltage and Load Current @25˚C

Power Dissipation (Watts)

30 40 50 60 70 80 85

0.5

1.5

2.5

3.5

4.5

UCH-12/4.2-D48 Maximum Current Temperature Derating at sea level

(VIN = 48V, airflow direction from VIN to VOUT, no baseplate)

Output Current (Amps)

Ambient Temperature (°C)

Natural Convection

0.42 0.84 1.26 1.68 2.1 2.52 2.94 3.36 3.78 4.2

UCH-12/4.2-D48 Efficiency and Power Dissipation

vs Line Voltage and Load Current @25˚C

Power Dissipation (Watts)

Efficiency (%)

Load Current (Amps)

= 75V

= 36V V

= 48V

Power Dissipation

= 48V)

TYPICAL PERFORMANCE DATA

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Single Output UCH Models

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MDC_UCH Models.A23 Page 11 of 18

Efficiency (%)

Load Current (Amps)

23455.54.53.52.51.5166.5

100

Power Dissipation

= 48V)

= 48V

= 75V

= 36V

UCH-15/6.7-D48 Efficiency and Power Dissipation

vs Line Voltage and Load Current @25˚C

Power Dissipation (Watts)

Output Current (Amps)

Ambient Temperature (°C)

400 lfm200 lfm

30 40 50 60 70 80

300 lfm

100 lfm

UCH-15/6.7-D48 Maximum Current Temperature Derating (at sea level)

No baseplate, VIN = 48V, transverse airflow

Output Current (Amps)

Ambient Temperature (°C)

400 lfm200 lfm

30 40 50 60 70 80

12.5

11.5

19.5

9.5

8.5

7.5

6.5

300 lfm

100 lfm

UCH-12/12.5-D48 Maximum Current Temperature Derating (at sea level)

No baseplate, VIN = 48V, transverse airflow

Efficiency (%)

Load Current (Amps)

5643 7 8 9 10 11 12

Power Dissipation

= 48V)

= 75V

= 48VV

= 36V

UCH-12/12.5-D48 Efficiency and Power Dissipation

vs Line Voltage and Load Current @25˚C

Power Dissipation (Watts)

TYPICAL PERFORMANCE DATA

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

www.murata-ps.com/support

Murata Power Solutions, Inc.

11 Cabot Boulevard, Mansﬁ eld, MA 02048-1151 U.S.A.

ISO 9001 and 14001 REGISTERED

Single Output UCH Models

Isolated, “Half-Brick”

1.8−15V Output DC/DC Converters

MDC_UCH Models.A23 Page 12 of 18

MECHANICAL SPECIFICATIONS

Bottom View

1.900

(48.26)

2.30

(58.4)

0.40

(10.2)

0.18

(4.6)

0.20

(5.1)

0.015 min. clearance

between standoffs and

highest component

0.400

(10.16)

0.700

(17.78)

0.50

(12.70)

1.000

(25.40)

1.400

(35.56)

2.40

(60.96)

Pin Diameters:

Pins 1-4, 6-8 0.040 ± 0.001 (1.016 ±0.025)

Pins 5, 9 0.080 ± 0.001 (2.032 ±0.025)

UCH with Optional Baseplate

0.18

(4.6)

0.50

(12.7)

2.40

(61.0)

2.00

(50.8)

1.90 (48.3)

2.30 (58.4)

0.015 minimum

clearance between

standoffs and

highest component

Do not remove

M3 x 0.50

threaded inserts

from bottom PCB

User’s thermal surface and hardware

Recommended threaded insert torque

is 0.35-0.55 N-M or 3-5 in-lbs.

M3 x 0.50

threaded insert

and standoff (4 places)

Screw length must

not go through Baseplate

Baseplate

Case C61

INPUT/OUTPUT CONNECTIONS

Pin Function P17

1 −Input

2 Case

3 On/Off Control

4 +Input

5 +Output

6 +Sense

7 Trim

8 −Sense

9 −Output

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 ± 2˚

Pin 2 may be removed under special order.

The case pin 2 is normally only used in

combination with the baseplate. Please

contact Murata Power Solutions.

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Standard pin length is shown. Please refer to the Part Number Structure

for special order pin lengths.

Single Output UCH Models

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MDC_UCH Models.A23 Page 13 of 18

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 Reverse-Polarity Protection

If the input voltage polarity is reversed, an internal body diode will become

forward biased and likely draw excessive current from the power source. If this

source is not current-limited or the circuit appropriately fused, it could cause

permanent damage to the converter. Please be sure to install a properly-

rated external input fuse (see Speciﬁ cations).

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 ca-

pacitor inputs), the converter shuts off and then restarts as the external capaci-

tor 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.

TECHNICAL NOTES Input Source Impedance

These converters will operate to speciﬁ cations without external components,

assuming that the source voltage has very low impedance and reasonable in-

put voltage regulation. Since real-world voltage sources have ﬁ nite impedance,

performance is improved by adding external ﬁ lter components. Sometimes only

a small ceramic capacitor is sufﬁ cient. Since it is difﬁ cult to totally characterize

all applications, some experimentation may be needed. Note that external input

capacitors must accept high speed switching currents.

Because of the switching nature of DC/DC converters, the input of these

converters must be driven from a source with both low AC impedance and

adequate DC input regulation. Performance will degrade with increasing input

inductance. Excessive input inductance may inhibit operation. The DC input

regulation speciﬁ es that the input voltage, once operating, must never degrade

below the Shut-Down Threshold under all load conditions. Be sure to use

adequate trace sizes and mount components close to the converter.

I/O Filtering, 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. External input capaci-

tors (Cin in the ﬁ gure) serve primarily as energy storage elements, minimizing

line voltage variations caused by transient IR drops in the input conductors.

Users should select input capacitors for bulk capacitance (at appropriate

frequencies), low ESR and high RMS ripple current ratings. In the ﬁ gure below,

the Cbus and Lbus components simulate a typical DC voltage bus. Your speciﬁ c

system conﬁ guration may require additional considerations. Please note that

the values of Cin, Lbus and Cbus will vary according to the speciﬁ c converter

model.

In critical applications, output ripple and noise (also referred to as periodic

and random deviations or PARD) may be reduced by adding ﬁ lter elements

such as multiple external capacitors. Be sure to calculate component tempera-

ture rise from reﬂ ected AC current dissipated inside capacitor ESR.

In the ﬁ gure, 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 half

inch and soldered directly to the ﬁ xture.

Figure 2. Measuring Input Ripple Current

BUS

= 33µF, ESR < 700mΩ @ 100kHz

BUS

= 220µF, ESR < 100mΩ @ 100kHz

BUS

= 12µH

+INPUT

−INPUT

CURRENT

PROBE

OSCILLOSCOPE

–

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Single Output UCH Models

Isolated, “Half-Brick”

1.8−15V Output DC/DC Converters

MDC_UCH Models.A23 Page 14 of 18

Floating Outputs

Since these are isolated DC/DC converters, their outputs are “ﬂ oating” with

respect to their input. The essential feature of such isolation is ideal ZERO

CURRENT FLOW between input and output. Real-world converters however do

exhibit tiny leakage currents between input and output (see Speciﬁ cations).

These leakages consist of both an AC stray capacitance coupling component

and a DC leakage resistance. When using the isolation feature, do not allow

the isolation voltage to exceed speciﬁ cations. Otherwise the converter may

be damaged. Designers will normally use the negative output (-Output) as

the ground return of the load circuit. You can however use the positive output

(+Output) as the ground return to effectively reverse the output polarity.

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. The temperature sensor is typically

located adjacent to the switching controller, approximately in the center of the

unit. See the Performance and Functional Speciﬁ cations.

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. As a practical matter,

it is quite difﬁ cult to insert an anemometer to precisely measure airﬂ ow in

most applications. Sometimes it is possible to estimate the effective airﬂ ow if

you thoroughly understand the enclosure geometry, entry/exit oriﬁ ce areas and

the fan ﬂ owrate speciﬁ cations.

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 Overvoltage Protection

This converter monitors its output voltage for an over-voltage condition. If

the output exceeds OVP limits, the sensing circuit will power down the unit,

and the output voltage will decrease. After a time-out period, the PWM will

automatically attempt to restart, causing the output voltage to ramp up to its

rated value. It is not necessary to power down and reset the converter for the

automatic OVP-recovery restart.

If the fault condition persists and the output voltage climbs to excessive

levels, the OVP circuitry will initiate another shutdown cycle. This on/off cycling

is referred to as “hiccup” mode. It safely tests full current rated output voltage

without damaging the converter.

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

As soon as the output current increases to approximately 125% to 150% of

its maximum rated value, the DC/DC converter will enter a current-limiting

mode. The output voltage will decrease proportionally with increases in output

current, thereby maintaining a somewhat constant power output. This is also

commonly referred to as power 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 particularly 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 (ap-

proximately 98% of nominal output voltage for most models), the magnetically

Figure 3. Measuring Output Ripple and Noise (PARD)

C1 = 0.1µF CERAMIC

C2 = 10µF TANTALUM

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

C2 R

LOAD

COPPER STRIP

SCOPE

+OUTPUT

+SENSE

−SENSE

−OUTPUT

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MDC_UCH Models.A23 Page 15 of 18

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 Sense Input

Use the Sense inputs with caution. Sense is normally connected at the load.

Sense inputs compensate for output voltage inaccuracy delivered at the load.

This is done by correcting IR voltage drops along the output wiring and the

current carrying capacity of PC board etch. This output drop (the difference be-

tween Sense and Vout when measured at the converter) should not be allowed

to exceed 0.5V. Consider using heavier wire if this drop is excessive. Sense

inputs also improve the stability of the converter and load system by optimizing

the control loop phase margin.

Note: The Sense input and power Vout lines are internally connected through

low value resistors to their respective polarities so that the converter can

operate without external connection to the Sense. Nevertheless, if the Sense

function is not used for remote regulation, the user should connect +Sense to

+Vout and –Sense to –Vout at the converter pins.

The remote Sense lines carry very little current. They are also capacitively

coupled to the output lines and therefore are in the feedback control loop to

regulate and stabilize the output. As such, they are not low impedance inputs

and must be treated with care in PC board layouts. Sense lines on the PCB

should run adjacent to DC signals, preferably Ground. In cables and discrete

wiring, use twisted pair, shielded tubing or similar techniques.

Any long, distributed wiring and/or signiﬁ cant inductance introduced into the

Sense control loop can adversely affect overall system stability. If in doubt, test

your applications by observing the converter’s output transient response dur-

ing step loads. There should not be any appreciable ringing or oscillation. You

may also adjust the output trim slightly to compensate for voltage loss in any

external ﬁ lter elements. Do not exceed maximum power ratings.

Please observe Sense inputs tolerance to avoid improper operation:

[Vout(+) −Vout(-)] − [Sense(+) −Sense(-)] ≤ 10% of Vout

Output overvoltage protection is monitored at the output voltage pin, not the

Sense pin. Therefore excessive voltage differences between Vout and Sense

together with trim adjustment of the output can cause the overvoltage protec-

tion circuit to activate and shut down the output.

Power derating of the converter is based on the combination of maximum

output current and the highest output voltage. Therefore the designer must

insure:

(Vout at pins) x (Iout) ≤ (Max. rated output power)

Trimming the Output Voltage

The Trim input to the converter allows the user to adjust the output voltage

over the rated trim range (please refer to the Speciﬁ cations). In the trim equa-

tions and circuit diagrams that follow, trim adjustments use either a trimpot or

a single ﬁ xed resistor connected between the Trim input and either the +Sense

or –Sense terminals. (On some converters, an external user-supplied precision

DC voltage may also be used for trimming). Trimming resistors should have a

low temperature coefﬁ cient (±100 ppm/deg.C or less) and be mounted close

to the converter. Keep leads short. If the trim function is not used, leave the

trim unconnected. With no trim, the converter will exhibit its speciﬁ ed output

voltage accuracy.

There are two CAUTIONs to be aware of for the Trim input:

CAUTION: To avoid unplanned power down cycles, do not exceed EITHER

the maximum output voltage OR the maximum output power when setting the

trim. Be particularly careful with a trimpot. If the output voltage is excessive,

the OVP circuit may inadvertantly shut down the converter. If the maximum

power is exceeded, the converter may enter current limiting. If the power is

exceeded for an extended period, the converter may overheat and encounter

overtemperature shut down.

CAUTION: Be careful of external electrical noise. The Trim input is a senstive

input to the converter’s feedback control loop. Excessive electrical noise may

cause instability or oscillation. Keep external connections short to the Trim

input. Use shielding if needed.

Figure 4. Remote Sense Circuit Conﬁ guration

LOAD

Contact and PCB resistance

losses due to IR drops

Contact and PCB resistance

losses due to IR drops

+OUTPUT

+SENSE

TRIM

−

SENSE

-OUTPUT

−

INPUT

ON/OFF

CONTROL

+INPUT

Sense Current

IOUT

Sense Return

IOUT Return

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MDC_UCH Models.A23 Page 16 of 18

VNOM is the nominal, untrimmed output voltage.

VOUT is the desired new output voltage.

Do not exceed the speciﬁed trim range or maximum power ratings

when adjusting trim. Use 1% precision resistors mounted close

to the converter on short leads.

Trim Down

Connect trim resistor between

trim pin and −Sense

RTrimDn (kΩ) = − 2

Where,

' VNOMINAL − VOUT

VNOMINAL

Trim Up

Connect trim resistor between

trim pin and +Sense

1.225 × '

VNOMINAL × (1 + ')

RTrimUp (kΩ) = − 2−1

Where,

' VOUT − VNOMINAL

VNOMINAL

Figure 5. Trim Connections Using A Trimpot

Figure 7. Trim Connections to Decrease Output VoltagesFigure 6. Trim Connections to Increase Output Voltages

LOAD

+OUT

+IN

–IN

ON/OFF TRIM

+SENSE

–OUT

–SENSE

LOAD

RTRIM DOWN

+OUT

+IN

–IN

ON/OFF TRIM

+SENSE

–OUT

–SENSE

LOAD

RTRIM UP

+OUT

+IN

–IN

ON/OFF TRIM

+SENSE

–OUT

–SENSE

Trim Equations

Trim Circuits

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MDC_UCH Models.A23 Page 17 of 18

Remote On/Off Control

On the input side, a remote On/Off Control can be ordered with either polarity.

Positive: Standard models are enabled when the On/Off pin is left open or

is pulled high to +Vin with respect to –Vin. An internal bias current causes

the open pin to rise to approximately +15V. Some models will also turn on at

lower intermediate voltages (see Speciﬁ cations). Positive-polarity devices are

disabled when the On/Off is grounded or brought to within a low voltage (see

Speciﬁ cations) with respect to –Vin.

Negative: Optional negative-polarity devices are on (enabled) when the On/

Off is grounded or brought to within a low voltage (see Speciﬁ cations) with

respect to –Vin. The device is off (disabled) when the On/Off is left open or is

pulled high to approximately +15V 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 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.

There are several CAUTIONs for the On/Off Control:

CAUTION: While it is possible to control the On/Off with external logic if

you carefully observe the voltage levels, the preferred circuit is either an open

drain/open collector transistor, a switch or a relay (which can thereupon be

controlled by logic) returned to negative Vin.

CAUTION: Do not apply voltages to the On/Off pin when there is no input

power voltage. Otherwise the converter may be permanently damaged.

Output Capacitive Load

These converters do not require external capacitance added to achieve rated

speciﬁ cations. Users should only consider adding capacitance to reduce switch-

ing noise and/or to handle spike current step loads. Install only enough ca-

pacitance to achieve noise objectives. Excess external capacitance may cause

regulation problems, slower transient response and possible instability. Proper

wiring of the Sense inputs will improve these factors under capacitive load.

The maximum rated output capacitance and ESR speciﬁ cation is given for a

capacitor installed immediately adjacent to the converter. Any extended output

wiring or smaller wire gauge or less ground plane may tolerate somewhat high-

er capacitance. Also, capacitors with higher ESR may use a larger capacitance.

Product Adaptations

Murata Power Solutions offers several variations of our core product family.

These products are available under scheduled quantity orders and may also

include separate manufacturing documentation from a mutually-agreeable

Product Speciﬁ cation. Since these product adaptations largely share a common

parts list, similar speciﬁ cations and test methods with their root products, they

are provided at excellent costs and delivery. Please contact MPS for details.

As of this date, the following products are available:

UCH-3.3/30-D48NBHL2-Y

UCH-5/10-D48NBHL2-Y

UCH-3.3/15-D48NBHL2-Y

UCH-3.3/35-D24NBHL2-Y

These are all negative On/Off polarity, baseplate installed, conformal coating

added, 3.68mm pin length, and RoHS-5 hazardous substance compliance (with

lead).

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

www.murata-ps.com/support

Murata Power Solutions, Inc.

11 Cabot Boulevard, Mansﬁ eld, MA 02048-1151 U.S.A.

ISO 9001 and 14001 REGISTERED

Single Output UCH Models

Isolated, “Half-Brick”

1.8−15V Output DC/DC Converters

MDC_UCH Models.A23 Page 18 of 18