MGJ6 14mm Series
10.2kVDC Isolated 6W Gate Drive SM DC-DC Converters
KDC_MGJ6-14mm.A04 Page 9 of 12
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EMC FILTERING AND SPECTRA
FILTERING
MGJ6D05XXXXWMC (Quasi-Peak) MGJ6D05XXXXWMC (Average)
MGJ6D12XXXXWMC (Quasi-Peak) MGJ6D12XXXXWMC (Average)
0
10
20
30
40
50
60
70
80
1.00E+05 1.00E+06 1.00E+07 1.00E+08
dBuV
Frequency (Hz)
0
10
20
30
40
50
60
70
80
1.00E+05 1.00E+06 1.00E+07 1.00E+08
dBuV
Frequency (Hz)
0
10
20
30
40
50
60
70
80
1.00E+05 1.00E+06 1.00E+07 1.00E+08
dBuV
Frequency (Hz)
The following filter circuit and filter table shows the input filters typically required to meet conducted emissions limits for EN 55022 curve B using Quasi-Peak (pink line)
and average (green line) detectors according to CISPR 22. The following plots show measurements of the positive (L1) and negative (L2) inputs for both Quasi-peak limit B
adherence and Average limit B adherence. If a high dv/dt above 80kV/us is expected from output to input it is advised that a common mode filter is used on the input without
Y capacitors. This will reduce the common mode current and reduce interference with primary side circuits.
C1, C2 & C3 Polyester or ceramic capacitor
C4 Electrolytic capacitor (note R1 could be omitted if C4 has ESR >= R1)
C1
L1
C2
C3
DC
DC
C4
R1
L2
TO MEET CURVE B
Part Number C1 L1 L2 C2&3 R1 C4
MGJ6D05XXXXWMC 3.3uF 47100SC
10nF
500m 470uF
MGJ6D12XXXXWMC 3.3uF 47100SC 10nF 500m 470uF
MGJ6D24XXXXWMC 3.3uF 47100SC
10nF
500m 470uF
0
10
20
30
40
50
60
70
80
1.00E+05 1.00E+06 1.00E+07 1.00E+08
dBuV
Frequency (Hz)
