BQ2092_15 Datasheet, PDF (1/30 Pages) Texas Instruments – Gas Gauge IC with SMBus-Like Interface

Obsolete Device
bq2092
Gas Gauge IC with SMBus-Like Interface
Features
➤ Provides accurate measure-
ment of available charge in
NiCd, NiMH, and Li-Ion re-
chargeable batteries
➤ Supports SBData charge con-
trol commands for Li-Ion,
NiMH, and NiCd chemistries
➤ Designed for battery pack inte-
gration
- 120µA typical operating
current
- Small size enables
implementations in as little as
3
4
square
inch
of
PCB
➤ Two-wire SMBus-like interface
➤ Measurements compensated for
current and temperature
➤ Programmable self-discharge
and charge compensation
➤ 16-pin narrow SOIC
General Description
The bq2092 Gas Gauge IC With
SMBus-Like Interface is intended
for battery-pack or in-system instal-
lation to maintain an accurate
record of available battery charge.
The bq2092 directly supports capac-
ity monitoring for NiCd, NiMH, and
Li-Ion battery chemistries.
The bq2092 uses the SMBus proto-
col that supports many of the Smart
Battery Data (SBData) commands.
The bq2092 also supports SBData
charge control. Battery state-of-
charge, capacity remaining, remain-
ing time and chemistry are available
over the serial link. Battery-charge
state can be directly indicated using
a four-segment LED display to
graphically depict battery full-to-
empty in 25% increments.
The bq2092 estimates battery self-
discharge based on an internal
timer and temperature sensor and
user-programmable rate informa-
tion stored in external EEPROM.
The bq2092 also automatically
recalibrates or “learns” battery
capacity in the full course of a
discharge cycle from full to empty.
The bq2092 may operate directly
from three nickel chemistry cells.
With the REF output and an exter-
nal transistor, a simple, inexpensive
regulator can be built to provide VCC
for other battery cell configurations.
An external EEPROM is used to
program initial values into the
bq2092 and is necessary for proper
operation.
Pin Connections
VCC
1
SCL
2
SDA
3
SEG1
4
SEG2
5
SEG3
6
SEG4
7
VSS
8
16
VOUT
15
REF
14
SCC
13
SCD
12
NC
11
SB
10
DISP
9
SR
16-Pin Narrow SOIC
PN209101.eps
Pin Names
VCC
SCL
SDA
SEG1
SEG2
SEG3
SEG4
VSS
3.0–5.5V
Serial memory
clock
Serial memory
data
LED segment 1
LED segment 2
LED segment 3
LED segment 4
System ground
SR
DISP
SB
SCD
SCC
REF
VOUT
Sense resistor input
Display control input
Battery sense input
Serial communication
data input/output
Serial communication
clock
Voltage reference
output
EEPROM supply
output
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