Datasheet

UWQ-12/17-Q48 Series
Wide Input, Isolated DOSA Quarter Brick DC/DC Converters
MDC_UWQ-12/17-Q48 Series.A06 Page 16 of 17
www.murata-ps.com/support
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 includ-
ed. 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
HP11947A Transient Limiter (Agilent)
OHMITE 25W – Resistor combinations
DC Source Programmable DC Power Supply Model 62012P-100-50
[3] Conducted Emissions Test Results
[4] Layout Recommendations
Most applications can use the fi ltering which is already installed inside the
converter or with the addition of the recommended external capacitors. For
greater emissions suppression, consider additional fi lter components and/or
shielding. Emissions performance will depend on the user’s PC board layout,
the chassis shielding environment and choice of external components. Please
refer to Application Note GEAN02 for further discussion.
Since many factors affect both the amplitude and spectra of emissions, we
recommend using an engineer who is experienced at emissions suppression.
Reference Part Number Description Vendor
L1 PE-62913 1mH, 6A Pulse
L3 500uH,10A, MPS 500uH,10A Murata
C8 2.2µFd Murata
C7 VZ Series
Qty 2 - Electrolytic Capacitor
22µFd, 100V
Panasonic
C16, C17 .22µFd Unknown
UWQ EMI 200W Test Card
48Vdc in, 12Vout, 17Amps
V+
V-
Black
Vin -
Vout -
Vout +Vin +
Resistive
Load
UUT
Resistive
Load
inside a
metal
container
L1
L3
C7
C16
C17
C8C8
C8
C8C8
C8
Figure 5. Conducted Emissions Test Circuit
Graph 1. Conducted emissions performance,
CISPR/EN55022, Class B, full load
[4
[4
[4
[4
[4
[4
[4
4
[4
[4
[4
[4
[4
[4
[4
[4
[4
[
[4
[4
4
4
[4
4
4
4
4
4
4
[4
[4
[4
[4
[4
[4
4
4
4
4
4
[4
4
4
[
[
[4
[4
[4
4
4
4
4
4
[4
[4
[4
[
[
[4
[4
4
4
4
4
[4
[4
[4
[4
4
4
[4
[4
4
4
4
[4
4
4
4
4
4
4
4
[4
4
4
[4
[4
[4
4
4
4
4
4
4
4
4
4
4
4
4
[4
4
[4
4
4
4
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
]
La
La
La
La
yo
yo
o
yo
o
yo
o
o
ut
ut
ut
ut
R
R
R
R
ec
ec
e
ec
e
ec
e
e
e
e
e
om
om
m
m
om
m
m
om
m
m
m
m
me
me
m
me
m
me
m
m
m
m
m
nd
d
d
d
nd
nd
nd
n
nd
n
n
n
n
n
n
at
t
at
at
at
at
t
at
a
a
at
t
at
a
t
t
io
i
io
o
io
o
o
io
o
o
o
o
o
o
o
ns
ns
n
ns
n
n
ns
n
n
n
n
n
n