LTC3554-2_15 Datasheet, PDF (33/36 Pages) Linear Technology – Micropower USB Power Manager with Li-Ion Charger and Two Step-Down Regulators

Typical Application
LTC3554/LTC3554-1/
LTC3554-2/LTC3554-3
4.35V TO 5.5V
USB INPUT
U1
20 _VBUS
V_OUT ¹⁸
R_PROG
1.87k
15 _NTC
CHRG ¹⁴
LTC3554
16 _PROG
BAT ¹⁷
SYSTEM LOAD
C1
10µF
+ _{3 CELL}
ALKALINE
OR LITHIUM
1 _HPWR
19 _SUSP
BVIN ¹²
C2
2.2µF
9 _{PWR_ON1}
2
10
4
8
3
5
PB1
FSEL
STBY
PGOOD
PWR_ON2
PBSTAT
ON
GND
SW1 ^{13 L1 10µH}
C3
10pF
FB1 ⁶
L2
11 ^10µH
SW2
C5
10pF
FB2 ⁷
2.5V
R_UP1
1M
R_LO1
464k
1.8V
R_UP2
590k
R_LO2
464k
C4
10µF
C6
10µF
R4
R2
R3
100k
100k
100k
U2
I/O
CORE
µC
PBSTAT
PGOOD
STBY
FSEL
EN
SUSP
HPWR
3554 F14
Figure 14. 3-Cell Alkaline/Lithium with PowerPath (Charger Disabled)
3554123ff
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