UEI15 Series

Isolated Wide Input Range 15-Watt DC/DC Converters

www.murata-ps.com

MDC_UEI15W.B21 Page 9 of 13

Trim Equations

–

2050

12775

–

2050

5110 (Vo - 2.5)

–

5110

25000

–

5110

10000 (Vo-2.5)

UEI15-050-Q12, Q48

UEI15-120-Q12, Q48

–

2050

12775

–

2050

5110 (Vo - 2.5)

UEI15-033-Q12, Q48

–

5110

25000

–

5110

10000 (Vo-2.5)

UEI15-150-Q12, Q48

Trim Up

<Connect trim

resistor between

Trim Down

<Connect trim

resistor between

Where Vo = Desired output voltage. Adjustment accuracy is subject to resis-

tor tolerances and factory-adjusted output accuracy. Mount trim resistor close

to converter. Use short leads.

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

voltages (see Specifications). Positive-polarity devices are disabled when the

On/Off is grounded or brought to within a low voltage (see Specifications) with

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

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

Dynamic control of the On/Off function should be able to sink appropriate

signal current when brought low and withstand appropriate voltage when

brought high. Be aware too that there is a finite time in milliseconds (see

Specifications) between the time of On/Off Control activation and stable,

regulated output. This time will vary slightly with output load type and current

and input conditions.

There are three CAUTIONs for the On/Off Control:

CAUTION: To retain full output circuit isolation, control the On/Off from the in-

put side ONLY. If you must control it from circuits in the output, use some form

of optoisolation to the On/Off Control. This latter condition is unlikely because

the device controlling the On/Off would have to remain powered on and not be

powered from the converter.

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

ON state, assuming positive logic.

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

power voltage. Otherwise the converter may be permanently damaged.

Figure 7 – Driving the On/Off Control Pin (suggested circuit)

ON/OFF CONTROL

CONTROL

+ Vcc

-INPUT

Soldering Guidelines

Murata Power Solutions recommends the specifications below when installing these

converters. These specifications vary depending on the solder type. Exceeding these

specifications may cause damage to the product. Be cautious when there is high atmo-

spheric humidity. We strongly recommend a mild pre-bake (100° C. for 30 minutes). 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:

Maximum Preheat Temperature

115° C.

Maximum Pot Temperature

270° C.

Maximum Solder Dwell Time

7 seconds

For Sn/Pb based solders:

Maximum Preheat Temperature

105° C.

Maximum Pot Temperature

250° C.

Maximum Solder Dwell Time

6 seconds