bq2056/T/V
Low-Dropout Li-Ion Charge-Control ICs with
AutoComp™ Charge-Rate Compensation
automatic charge-rate compensation
General Description
Features
(AutoComp) and a trickle-charger in-
terface output for reviving deeply
discharged cells. The bq2056 sup-
ports a single-cell 4.1V pack and the
2056T supports a two-cell 8.2V pack.
The bq2056V may be externally pro-
grammed for supporting other volt-
ages. All versions feature a sleep
mode for low-power applications.
➤ Significant reduction in charge
time with AutoComp charge-rate
compensation
The bq2056 series ICs are low-cost
precision linear charge-control de-
vices for Li-Ion batteries. With a
minimum number of external compo-
nents, the bq2056 is a complete low-
dropout linear charger. The dropout
voltage is typically less than 0.5V
when the bq2056 is used with an ex-
ternal PNP transistor or P-channel
FET. Features include proprietary
➤ Ideal for low-dropout linear regu-
lator design
➤ 1-cell, 2-cell, and programmable
multicell versions
➤ Low-cost charger implementation
with minimum number of exter-
nal components
Functional Block Diagram
➤ Programmable current limit to
accommodate any battery size
+
➤ Interface to external trickle
charger for reviving deeply dis-
charged batteries
SNS
TRKL
2.0V
➤ High-accuracy charge control
BAT
KCOMP
➤ Sleep mode for low power con-
COMP
+
sumption
VREG
CC
➤ Direct battery voltage sense
without resistive dividers
(bq2056 and bq2056T)
SNS
100mV
+
VSS
INH
➤ Small 8-pin SOIC package
BDbq2056.eps
Pin Names
Pin Connections
INH
Charge-inhibit input
SNS
BAT
CC
Current sense input
Battery voltage input
INH
1
2
3
4
8
7
6
5
V
CC
TRKL
Trickle-charge
interface output
TRKL
CC
Charge control
output
VSS
Ground
V
SS
BAT
SNS
COMP
Charge-rate
compensation input
VCC
Supply input
COMP
8-Pin DIP or Narrow SOIC
PN-205601.eps
10/98 B
1
TI [ TEXAS INSTRUMENTS ]
