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SDC_DSQ_DAQ_DCQ0150V2.A04.D02 Page 17 of 25

DSQ/DAQ/DCQ Series

600W Quarter Brick

DOSA Digital PMBus Interface

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 informa-

tion is listed in the Product Specifications. An external discrete filter is installed

and the circuit diagram is shown below.

[2] Conducted Emissions Test Equipment Used

Hewlett Packard HP8594L Spectrum Analyzer – S/N 3827A00153

2 Line V-networks LS1-15V 50Ω/50Uh Line Impedance Stabilization Network

LOAD

C2

L1

C6 C7

DC/DC

C12

+

+

VCC

RTN

-48V

GND

GND

C3

C1

L2

C5

C4

C8

C9 C10 C11

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

[1] Conducted Emissions Parts List

[3] Conducted Emissions Test Results

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

[4] Layout Recommendations

Most applications can use the filtering which is already installed inside the

converter or with the addition of the recommended external capacitors. For greater

emissions suppression, consider additional filter components and/or shielding.

Emissions performance will depend on the user’s PC board layout, the chassis

shielding environment and choice of external components.

Since many factors affect both the amplitude and spectra of emissions, we

recommend using an engineer who is experienced at emissions suppression.