Datasheet

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UEI30 Series
30W Isolated Wide-Range DC-DC Converters
MDC_UEI Series 30W.B02 Page 16 of 18
There are two 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 or a relay (which can thereupon be controlled by
logic). The On/Off prefers to be set at approx. +15V (open pin) for the 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)
1
3
ON/OFF
CONTROL
-VIN
+VCC
Reference Description
L1 500μH, 4.1A
C8 Electrolytic Capacitor 100μfd, 100V
C1, C2, C3 C4, C5, C6, C7 3.3μfd, 50V
Figure 8. Conducted Emissions Test Circuit
48 Vdc in,
MODEL# UEI30-050-Q48N-C
30W
5 Vout,
6 Amps
V+
V-
Vin -
Vout -
Vout +Vin +
Load
Resistive
UUT
Load
Resistive
inside a
metal
L1
container
C7
C4
C5
C6
C2C1 C3
C8
Graph 1. Conducted emissions performance with fi lter, Negative Line, CISPR 22,
Class B, full load, for UEI30-033-Q48N-C
dBμV
80
-20
-10
0
10
20
30
40
50
60
70
MHz
30.0
0.15 1.0
10.0
CONAV
Emissions Performance
Murata Power Solutions measures its products for radio frequency emissions
against the EN 55022 and CISPR 22 standards. Passive resistance loads are
employed and the output is set to the maximum voltage. If you set up your
own emissions testing, make sure the output load is rated at continuous power
while doing the tests.
The recommended external input and output capacitors (if required) are
included. Please refer to the fundamental switching frequency. All of this
information is listed in the Product Specifi cations. An external discrete fi lter is
installed and the circuit diagram is shown below.
[1] Conducted Emissions Parts List
[2] Conducted Emissions Test Equipment Used

Rohde & Schwarz EMI Test Receiver (9KHz – 1000MHz) ESPC

Rohde & Schwarz Software ESPC-1 Ver. 2.20

OHMITE 25W – 1 Ohm resistor combinations

DC Source Programmable DC Power Supply Model 62012P-100-50
[3] Conducted Emissions Test Results