Figure 6-5. Radiated EMI Measurement with
Horizontal Log Antenna Under CISPR 25 Class 5
Limits
Figure 6-6. Radiated EMI Measurement with
Vertical Log Antenna Under CISPR 25 Class 5
Limits
6.2 Board Efficiency
This section provides efficiency plots for the board with LMQ61460AAS populated for Auto mode efficiency and
LMQ61460AFS populated for FPWM mode efficiency. For 2.1-MHz data, the output stage has to be changed
from the default BOM. The inductor (L1) selected was XEL5030-102MEB.
Load Current (A)
Ef
fic
ie
nc
y
(%
)
0.0001
0.001
0.01
0.1 0.2 0.5 1
2 3 5 710
60%
65%
70%
75%
80%
85%
90%
95%
100%
LM61
V
IN
= 8 V
V
IN
= 13.5 V
V
IN
= 24 V
Figure 6-7. F
SW
= 400 kHz, 5 VOUT, Auto Mode
Load Current (A)
Ef
fic
ie
nc
y
(%
)
0
1
2
3
4
5
6
7
50%
55%
60%
65%
70%
75%
80%
85%
90%
95%
100%
LM61
V
IN
= 8 V
V
IN
= 13.5 V
V
IN
= 24 V
Figure 6-8. F
SW
= 400 kHz, 5 VOUT, FPWM Mode
Output Current (A)
Ef
fic
ie
nc
y
(%
)
0.001
0.010.02 0.05 0.1 0.2
0.5
1
2 3 4 5 7 10
60%
65%
70%
75%
80%
85%
90%
95%
100%
LM61
V
IN
= 8 V
V
IN
= 13.5 V
V
IN
= 24 V
Figure 6-9. F
SW
= 400 kHz, 3.3 VOUT, Auto Mode
Output Current (A)
Ef
fic
ie
nc
y
(%
)
0
1
2
3
4
5
6
7
50%
55%
60%
65%
70%
75%
80%
85%
90%
95%
100%
LM61
V
IN
= 8 V
V
IN
= 13.5 V
V
IN
= 24 V
Figure 6-10. F
SW
= 400 kHz, 3.3 VOUT, FPWM Mode
LMQ61460EVM-400K Board Test Results
SNVU698B – SEPTEMBER 2020 – REVISED DECEMBER 2020
LMQ61460EVM-400K User's Guide
13
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