BQ2057CSN BENCHMARQ, BQ2057CSN Datasheet - Page 7

• Manufacturer Part Number: BQ2057CSN
• Description: PROG BATTERY CHARGER, 2057, SOIC8
• Manufacturer: BENCHMARQ

Specifications of BQ2057CSN

• Battery Type: Li-Ion / Li-Polymer
• Input Voltage: 15V
• Battery Charge Voltage: 4.2V
• Charge Current Max: 2A
• Battery Ic Case Style: SOIC
• No. Of Pins: 8
• No. Of Series Cells: 1
• Operating Temperature: RoHS Compliant

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.
GND
DC+
0.1 µF
R SNS
0.2 Ω
C2
Figure 1. Low Dropout Single- or Two-Cell Li-Ion/Li-Pol Charger
FZT788B
Q1
R1
1 kΩ
CC
SNS
VCC
VSS
APPLICATION INFORMATION
bq2057
COMP
STAT
BAT
TS
www.ti.com
V CC
R2
2 kΩ
D1
V CC
R T2
R T1
C1
0.1 µF
PACK+
PACK−
TEMP
SLUS025F − MAY 2001 − REVISED JULY 2002
Battery
Pack
NTC
7