UEI15 Series

Isolated Wide Input Range 15-Watt DC/DC Converters

www.murata-ps.com

email: sales@murata-ps.com

14 Mar 2011

MDC_UEI15W.B42 Page 4 of 16

Absolute Maximum Ratings

Absolute maximums 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 is neither implied nor recommended.

(4) Mean Time Before Failure is calculated using the Telcordia (Belcore) SR-

332 Method 1, Case 3, ground fixed conditions, Tpcboard=+25 deg.C, full load,

natural air convection.

(5) The On/Off Control is normally controlled by a switch. But it may also be

driven with external logic or by applying appropriate external voltages which

are referenced to Input Common. The On/Off Control Input should use either an

open collector or open drain transistor.

(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. This

may damage the outputs.

(8) Output noise may be further reduced by adding an external filter. See

I/O Filtering and Noise Reduction.

(9) All models are fully operational and meet published specifications,

including “cold start” at –40°C.

(10) Regulation specifications describe the deviation as the line input voltage

or output load current is varied from a nominal midpoint value to either extreme.

(11) The output overvoltage protection is automatic recovery after fault

removal. 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.

(13) Do not exceed maximum power specifications when adjusting the

output trim.

(14) At zero output current, the output may contain low frequency com-

ponents which exceed the ripple specification. The output may be operated

indefinitely 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

with nominal input voltage.

(16) “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 con-

verter immediately recovers normal operation.

downwards from +5.0V (more negative).

(18) Shown at Vin = 10V.

CAUTION: This product is not internally fused. To comply with safety

agency certifications and to avoid injury to personnel or equipment, the user

must connect an external fast-blow fuse to the input terminals. See fuse

information.

(19) All models require 10% of Imax minimum output load to meet specifi-

cations. However, they will not be damaged at zero output load.

SPECIFICATION NOTES

(1) All models are tested and specified with external capacitors listed in the

table below. The external capacitors listed below are ONLY for establishing test

specifications. They are required for our test fixtures and equipment. Your applica-

tion may not need them. The converter is stable with no external capacitors but

Murata Power Solutions strongly recommends external caps. All caps are low-ESR

types. Where two or more capacitors are listed, these are connected in parallel. All

caps should mount close to the DC/DC using short leads.

All specifications are typical unless noted. General conditions for Specifica-

must be supplied for extended testing under power.

(2) Input Ripple Current is tested and specified over a 5 Hz to 20 MHz band-

(3) Note that Maximum Power Derating curves indicate an average current at

nominal input voltage. At higher temperatures and/or lower airflow, the DC/DC

converter will tolerate brief full current outputs if the total RMS current over time

does not exceed the Derating curve. All Derating curves are presented at sea level

altitude. Be aware of reduced power dissipation with increasing density altitude.

ABSOLUTE MAXIMUM RATINGS

Input

Voltage

Q12 models

Volts Max. continuous

36 VDC

Volts, transient 100mS

50 VDC

Q48 models

Volts Max. continuous

75 VDC

Volts, transient 100mS

100 VDC

On/Off control,

Volts, Min.

–0.3

Volts, Max.

15

Input Reverse Polarity Protection

See fuse section

Output Overvoltage, Volts Max.

Output Current, sustained short circuit

Current-limited, see specs

Storage Temperature

Range, Min. ºC

-55

Max. ºC

+125

INPUT/OUTPUT EXTERNAL TEST CAPACITORS

Model

Input Capacitor

Output Capacitor(s)

UEI15-033-Q12

100 μF

1 μF & 10 μF

UEI15-033-Q48

4.7 μF ceramic

1 μF & 10 μF

UEI15-050-Q12

100 μF

1 μF & 10 μF

UEI15-050-Q48

4.7 μF ceramic

1 μF & 10 μF

UEI15-120-Q12

100 μF

1 μF & 10 μF

UEI15-120-Q48

4.7 μF ceramic

1 μF & 10 μF

UEI15-150-Q12

100 μF

1 μF & 10 μF

UEI15-150-Q48

4.7 μF ceramic

1 μF & 10 μF