BQ2057CSN BENCHMARQ, BQ2057CSN Datasheet - Page 18

• 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

18
SLUS025F − MAY 2001 − REVISED JULY 2002
automatic charge-rate compensation (continued)
DC+
AutoComp setup requires the following information:
D
D
The voltage drop across the internal impedance of battery pack, V
equation:
The required compensation is then calculated using the following equations:
Where V
configuration and to VSS for low-side sensing. V
The values of R
DC−
Total impedance of battery pack (Z
Maximum charging current (I
V
V
V
V
(Z)
V
(COMP)
(PACK)
(COMP)
(SNS)
R COMP2
(COMP)
= Z
R SNS
(PACK)
High-Side Current Sensing
+ V
(COMP1)
+
+
is the voltage on COMP pin. This voltage is referenced to VCC in high-side current sensing
G
R
O(REG)
× I
(COMP)
COMP1
V
R COMP1
(REG)
(Z)
SNS
BAT
VCC
TS
and R
R
COMP2
) G
bq2057
) R
(COMP2)
(REG)
COMP
COMP2
APPLICATION INFORMATION
(COMP)
STAT
VSS
Figure 13. AutoComp Circuits
CC
)
(PACK)
can be calculated using the following equation:
)
V
www.ti.com
(COMP
(PACK)
BAT+
is the voltage across the battery pack.
DC−
DC+
(Z)
, can then be calculated using the following
Low-Side Current Sensing
SNS
BAT
VCC
TS
R SNS
bq2057
R COMP2
COMP
STAT
VSS
CC
R COMP1
BAT+
BAT−
(13)
(14)
(15)