Datasheet

LTC3101
31
3101fb
Sequenced Start-Up, Buck-Boost Followed by Buck Converters
BAT1
USB1
C
RS
PWRKEY
PWRON
PBSTAT
R1
50k
R2
50k
RESET
USB2
FB3
LDO
SW2
FB2
HSO
MAX
PWM
ENA3
ENA2
ENA1
C2
10μF
C3
10μF
2 AA
CELLS
USB POWER
4.3V TO 5.5V
C4
10μF
R3
1M
V
OUT3
= 3.3V
300mA FOR V
IN
≥ 1.8V
800mA FOR V
IN
≥ 3V
R4
221k
R5
100k
4.7μH
TRACKING OUTPUT
200mA
Hot Swap OUTPUT
3.3V
100mA
C6
4.7μF
C7
4.7μF
C8
4.7μF
C5
0.1μF
1.8V
50mA
V
OUT2
1.8V
350mA
V
OUT1
1.2V
350mA
C10
10μF
R6
221k
R7
110k
4.7μH
SW1
FB1
C12
10μF
C11
22pF
C9
22pF
3101 TA05a
R8
221k
R9
221k
4.7μH
C1
0.033μF
ON/OFF
BAT2 SW3A
LTC3101
GND
SW3B OUT3
+
μP
V
OUT1
Power-Up Waveforms
TYPICAL APPLICATIONS
PWRKEY 5V/DIV
PBSTAT 2V/DIV
OUTPUT
VOLTAGES
1V/DIV
C
RS
2V/DIV
RESET 2V/DIV
10ms/DIV
3101 TA05b
V
OUT3
V
OUT1
V
OUT2