LT1610
APPLICATIONS INFORMATION
A SEPIC (Single-Ended Primary Inductance Converter)
schematic is shown in Figure 4. This converter topology
produces a regulated output over an input voltage range
that spans (i.e., can be higher or lower than) the output.
Recommended component placement for a SEPIC is
shown in Figure 5.
C3
1µF
CERAMIC
INPUT
Li-ION
3V to 4.2V
6
V
IN
+
C1
22µF
6.3V
1
8
C1, C2: AVX TAJA226M006
C3: AVX 1206YC105 (X7R)
SHUTDOWN
D1: MOTOROLA MBR0520
L1, L2: MURATA LQH3C220 (UNCOUPLED)
OR SUMIDA CLS62-220 (COUPLED)
Figure 4. Li-Ion to 3.3V SEPIC DC/DC Converter
GROUND PLANE
R1
R2
SHUTDOWN
1
2
3
4
MULTIPLE
VIAs
GND
LT1610
8
7
6
5
C1
C2
+
Figure 5. Recommended Component Placement for SEPIC
U
W
U
U
L1
22µH
•
5
SW
FB
2
604k
SHDN
PGND
4
3
D1
V
OUT
3.3V
120mA
1M
•
L2
22µH
V
C
LT1610
COMP
GND
7
+
C2
22µF
6.3V
1610 F04
V
IN
+
L1
L2
C3
D1
V
OUT
1610 F05
7
LINER [ LINEAR TECHNOLOGY ]
