Datasheet

LTC3857-1
30
38571fc
TYPICAL APPLICATIONS
Figure 13. High Efficiency Dual 3.3V/8.5V Step-Down Converter
SENSE1
+
SENSE1
–
SENSE2
–
SENSE2
+
V
FB1
I
TH1
SGND
EXTV
CC
RUN1
RUN2
FREQ
TRACK/SS2
V
FB2
TRACK/SS1
PLLIN/MODE
PGOOD1
BG1
SW1
BOOST1
TG1
V
IN
INTV
CC
PGND
TG2
BG2
BOOST2
SW2
C1
1nF
R
B1
215k
C
OUT1
, C
OUT2
: SANYO 10TPD150M
D1, D2: CENTRAL SEMI CMDSH-4E
L1: SUMIDA CDEP105-3R2M
L2: SUMIDA CDEP105-7R2M
MTOP1, MTOP2, MBOT1, MBOT2: VISHAY Si7848DP
C
F1
15pF
C
ITH1A
150pF
C
SS1
0.1µF
C
SS2
0.1µF
C
ITH1
820pF
C
INT
4.7µF
C
B1
0.47µF
C
B2
0.47µF
D1
V
IN
9V TO 38V
D2
LTC3857-1
L1
3.3µH
L2
7.2µH
R
SENSE1
6m
R
SENSE2
8m
MBOT1
MTOP2
MTOP1
MBOT2
38571 F12
100k
INTV
CC
C
OUT1
150µF
V
OUT1
3.3V
5A
V
OUT2
8.5V
3A
C
IN
22µF
C
OUT2
150µF
R
A1
68.1k
R
A2
44.2k
R
B2
422k
C
F2
39pF
R
ITH1
15k
C2
1nF
I
TH2
C
ITH2
680pF
C
ITH2A
100pF
R
ITH2
27k