Datasheet

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Emissions Performance
Murata Power Solutions measures its products for conducted 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
Hewlett Packard HP8594L Spectrum Analyzer – S/N 3827A00153
2Line V-networks LS1-15V 50/50Uh Line Impedance Stabilization Network
[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 GEAN-02 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
C1, C2, C3, C4, C5 GRM32ER72A105KA01L
SMD CERAMIC-100V-
1000nF-X7R-1210
Murata
C6 GRM319R72A104KA01D
SMD CERAMIC100V-100nF-
±10%-X7R-1206
Murata
L1, L2 PG0060T
COMMON MODE-473uH-
±25%-14A
Pulse
C8, C9, C10, C11 GRM55DR72J224KW01L
SMD CERAMIC630V-0.22uF-
±10%-X7R-2220
Murata
C7 UHE2A221MHD
Aluminum100V-220Uf-
±10%-long lead
Nichicon
C12 NA
LOAD
C2
L1
C6 C7
DC/DC
C12
++
VCC
RTN
-48V
GND
GND
C3C1
L2
C5C4
C8 C9 C10 C11
Figure 6. Conducted Emissions Test Circuit
Graph 1. Conducted emissions performance, Positive Line,
CISPR 22, Class B, full load
Graph 2. Conducted emissions performance, Negative Line,
CISPR 22, Class B, full load
DBQ/DVQ Series
420W Digital Fully Regulated Intermediate
DC-DC Bus Converter
MDC_DBQ Series.B02Δ Page 30 of 31