Datasheet

 
 
SLUS025F − MAY 2001 − REVISED JULY 2002
7
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APPLICATION INFORMATION
CC
SNS
VCC
VSS
COMP
BAT
TS
STAT
bq2057
V
CC
R1
1 kΩ
D1
R2
2 kΩ
R
T2
R
T1
V
CC
TEMP
PACK−
PACK+
C1
0.1 µF
NTC
Battery
Pack
C2
0.1 µF
DC+
GND
R
SNS
0.2 Ω
Q1
FZT788B
Figure 1. Low Dropout Single- or Two-Cell Li-Ion/Li-Pol Charger
functional description
The bq2057 is an advanced linear charge controller for single or two-cell Li-Ion or Li-Pol applications. Figure 1
shows the schematic of charger using a PNP pass transistor. Figure 2 is an operational state diagram, and
Figure 3 is a typical charge profile. Figure 4 shows the schematic of a charger using P-channel MOSFET.