Datasheet

LTC3455/LTC3455-1
9
3455fc
BLOCK DIAGRAM
1.23V
3.9V
+
–
–
+
11
10
13
14
1Ω
4.7μF
1μF
10μF
WALLFB
V
MAX
HSI
HSO
WALL 5V
3.3V, HS
V
MAX
3.32k
1.24k
8
6
5
9
1Ω
4.7μF
USB
5V
USB
SUSPEND
USBHP
EXTPWR
USB POWER MANAGER
REF
+
–
1k
R
4R
V
BAT
3.3V to 4.2V
BATTERY CHARGER
BATTERY PMOS SWITCH
2.41R
R
CHARGE
CONTROL
1.23V
1 1000
1 1000
–
+
4
2
3
EXTPWR
UVLO
ON/OFF
ENABLE
+
–
0.8V
PWM
DRIVER
25
1
7
SW1
FB1
100k
4.7μH
80.6k
10μF
1.8V
ENABLE
+
–
0.8V
PWM
DRIVER
18
12
SW2
FB2
249k
4.7μH
80.6k
10μF
HOT SWAP
SWITCHER 2
SWITCHER 1
3.3V
CHRG
TIMER
PROG
GND
16
AI
17
AO
24
ON
23
PBSTAT
20
RST
21
MODE
19
ON2
22
PWRON
200ms RESET PULSE
BURST MODE ENABLE
15
HSON
V
BAT
2.49k
0.1μF
V
MAX
806k
806k
1.8V
2.43M
4.7μF
+
–
0.8V
806k
1.8V
V
BAT
3.0V
–
+
3455 BD01
μC
USB
CONTROLLER
LBO
ENABLE
+
–
+
5.6V