BQ2052_15 Datasheet, PDF (1/20 Pages) Texas Instruments – Gas Gauge IC

Not Recommended For New Designs
Preliminary bq2052
Features
➤ Accurate measurement of avail-
able capacity in Lithium primary
batteries such as Lithium Sul-
phur Dioxide and Lithium Man-
ganese Dioxide
➤ Provides a low-cost battery moni-
tor solution for pack integration
- Complete circuit can fit less
than 1 square inch of PCB
space
- Low operating current
- Less than 100nA of data
retention current
➤ Single-wire communication inter-
face (HDQ bus) for critical battery
parameters
➤ Communicates remaining capac-
ity with direct drive of LEDs in 3
selectable modes
➤ Measurements automatically
compensated for discharge rate
and temperature
➤ 16-pin narrow SOIC
Gas Gauge IC
for Lithium Primary Cells
General Description
The bq2052 Lithium Primary Gas
Gauge IC is intended for bat-
tery-pack or in-system installation
to maintain an accurate record of
available battery capacity. The IC
monitors a voltage drop across a
sense resistor connected in series
with the cells to determine dis-
charge activity of the battery. The
bq2052 applies compensations for
battery temperature and discharge
rate to the available charge counter
to provide available capacity infor-
mation across a wide range of oper-
ating conditions.
Compensated available capacity
may be directly indicated using an
LED display. The LED display is
programmable and can be config-
ured as two, four, or five segments.
These segments are used to depict
available battery capacity. The
bq2052 supports a single-wire serial
communications link to an external
micro-controller. The link allows
the micro-controller to read and
write the internal registers of the
bq2052. The internal registers in-
clude available battery capacity,
voltage, temperature, current, and
battery status. The controller may
also overwrite some of the bq2052
gas gauge data registers.
The bq2052 can operate from the
batteries in the pack. The REF out-
put and an external FET provide a
simple, inexpensive voltage regula-
tor to supply power to the circuit
from the cells.
Pin Connections
LCOM
1
SEG1/PROG1
2
SEG2/PROG2
3
SEG3/PROG3
4
SEG4/PROG4
5
SEG5/PROG5
6
PROG6
7
VSS
8
16
VCC
15
REF
14
CP
13
HDQ
12
RBI
11
SB
10
DISP
9
SR
16-Pin Narrow SOIC
PN2052H1.eps
SLUS019–MAY 1999
Pin Names
LCOM
LED common output
SEG₁/PROG₁ LED segment 1/
program 1 input
SEG₁/PROG₂ LED segment 2/
program 2 input
SEG₁/PROG₃ LED segment 3/
program 3 input
SEG₁/PROG₄ LED segment 4/
program 4 input
SEG₁/PROG₅ LED segment 5/
program 5 input
CP
Control port
1
V_SS
SR
DISP
SB
RBI
HDQ
PROG₆
REF
V_CC
System ground
Sense resistor input
Display control input
Battery sense input
Register backup input
Serial communications
input/output
Program 6 input
Voltage reference output
Supply voltage