L4971
Typical Performance (Using Evaluation Board) fsw = 100kHz
Output
Voltage
3.3V
5.1V
12V
Output
Ripple
10mV
10mV
12mV
Efficiency
V
CC
=35V I
O
= 1.5A
84 (%)
86 (%)
93 (%)
Line Regulation
I
o
= 1.5A V
CC
= 8 to 55V
3mV
3mV
3mV (V
CC
=15 to 55V)
Load Regulation
V
CC
=35V I
O
= 0.5 to 1.5A
6mV
6mV
4mV
Figure 1. Test and valuation board circuit.
Vi=8V to 55V
5
R
1
20K
3
C
1
220µF
63V
C
7
220nF
C
2
2.7nF
2
7
8
L4971
4
1
6
L1
126µH
(77120)
D1
GI
SB360
C
8
330µF
V
O
=3.3V/1.5A
R
3
C
5
100nF
R
2
9.1K
C
4
22nF
C
6
100nF
R
4
D97IN749A
C1=220µF/63V EKE
C2=2.7nF
C5=100nF
C6=100nF
C7=220nF/63V
C8=330µF/35V CG Sanyo
L1=126µH KoolMu 77120 - 65 Turns - 0.5mm
R1=20K
R2=9.1K
D1=GI SB360
L4971
V
O
(V)
3.3
5.1
12
15
18
24
R3(KΩ)
0
2.7
12
16
20
30
4.7
4.7
4.7
4.7
4.7
R4(KΩ)
Figure 2. PCB and component layout of the figure 1.
5/12
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