LTC3556 Datasheet, PDF (34/36 Pages) Linear Technology – High Effi ciency USB Power Manager with Dual Buck and Buck-Boost DC/DCs

LTC3556
TYPICAL APPLICATION
Watchdog Microcontroller Operation
USB/WALL
4.5V TO 5.5V
C1
10μF
100k
T
8.25Ω
2k
25
V_BUS
3
NTC
20
PROG
2
CLPROG
0.1μF ^3.01k
SW ²⁶
V_OUT ²⁴
GATE ²²
BAT ²³
GND ²⁹
CHRG ²¹
V_OUT3 ¹²
L1
3.3μH
MP1
+
Li-Ion
10pF
C2
22μF
RED
121k
510Ω
TO OTHER
LOADS
2.5V TO
3.3V
1A
HDD
PUSHBUTTON
MICROCONTROLLER
1
1μF ¹⁰
2 _13,16
LDO3V3
DV_CC
8
V_{C3 7}
FB3
14
SWCD3
9
SWAB3
V_IN3 ¹¹
LTC3555
SW2 ¹⁹
FB2 ¹⁷
I²C (SCL, SDA)
330pF
15k
324k
105k
L2
2.2μH
L3
4.7μH
1.02M
10pF
806k
33pF
10μF
22μF
2.2μF
1μF
C1: MURATA GRM21BR61A106KE19
C2: TDK C2012X5R0J226M
L1: COILCRAFT LPS4018-332LM
L2: COILCRAFT LPS4018-222MLC
L3, L4: TOKO 1098AS-4R7M
MP1: SILICONIX Si2333
28
27
ENALL
SEQ
V_IN2 ¹⁸
SW1 ⁴
L4
4.7μH
806k
FB1 ⁶
806k
10pF
10μF ^1μF
1.8V
400mA
I/O
MICROPROCESSOR
0.8V TO
1.6V
400mA
CORE
POR
10k
V_IN1 ⁵
PGOODALL ¹⁵
3556 TA02
3556f
34