BQ2013H Datasheet, PDF (1/24 Pages) Texas Instruments – Gas Gauge IC for Power- Assist Applications

bq2013H
Features
➤ Accurate measurement of available
charge in rechargeable batteries
➤ Designed for electric assist bicycles
and other applications
➤ Measures a wide dynamic current
range
➤ Supports NiCd, NiMH or lead acid
➤ Designed for battery pack inte-
gration
- 120µA typical standby current
(self-discharge estimation mode)
- Small size enables imple-
mentations
in
as
little
as
1
2
square inch of PCB
➤ Direct drive of LEDs for capacity
display
➤ Automatic charge and self-
discharge compensation using in-
ternal temperature sensor
➤ Simple single-wire serial commu-
nications port for subassembly
testing
➤ 16-pin narrow SOIC
Gas Gauge IC for Power-
Assist Applications
General Description
The bq2013H Gas Gauge IC is in-
tended for battery-pack installation to
maintain an accurate record of a bat-
tery’s available charge. The IC moni-
tors a voltage drop across a sense resis-
tor connected in series between the
negative battery terminal and ground
to determine charge and discharge ac-
tivity of the battery. The bq2013H is
designed for high cpaacity battery
packs used in high-discharge rate sys-
tems.
Battery self-discharge is estimated
based on an internal timer and tem-
perature sensor. Compensations for
battery temperature, rate of charge,
and self-discharge are applied to the
charge counter to provide available
capacity information across a wide
range of operating conditions. Initial
battery capacity, self-discharge rate,
display mode, and charge compensa-
tion are set using the PROG_1-6 pins.
Actual battery capacity is automati-
cally “learned” in the course of a dis-
charge cycle from full to empty.
Nominal available charge may be
directly indicated using a five-seg-
ment LED display. These segments
are used to graphically indicate
nominal available charge.
The bq2013H supports a simple
single-line bi-directional serial link to
an external processor (common
ground). The bq2013H outputs bat-
tery information in response to exter-
nal commands over the serial link. To
support battery pack testing, the
outputs may also be controlled by
command. The external processor
may also overwrite some of the
bq2013H gas gauge data registers.
The bq2013H may operate directly
from four nickel cells or three lead
acid. With the REF output and an
external transistor, a simple, inexpen-
sive regulator can be built to provide
V_CC from a greater number of cells.
Internal registers include available
charge, temperature, capacity, battery
ID, and battery status.
Pin Connections
Pin Names
LCOM
1
SEG1/PROG1
2
SEG2/PROG2
3
SEG3/PROG3
4
SEG4/PROG4
5
SEG5PROG5
6
PROG6
7
VSS
8
16
VCC
15
REF
14
DONE
13
HDQ
12
RBI
11
SB
10
DISP
9
SR
16-Pin Narrow SOIC
PN2013.eps
SLUS120–MAY 1999 B
LCOM
LED common output
REF
SEG₁/PROG₁ LED segment 1/ Program DONE
1 input
SEG₂/PROG₂ LED segment 2 / Program HDQ
2 input
SEG₃/PROG₃ LED segment 3/ Program
3 input
SEG₄/PROG₄ LED segment 4/ Program
4 input
RBI
SB
DISP
SEG₅/PROG₅ LED segment 5/ Program SR
5 input
V_CC
PROG₆
Program 6 input
1
Voltage reference output
Fast charge complete
input
Serial communications
input/output
Register backup input
Battery sense input
Display control input
Sense resistor input
Supply voltage