Features
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Complete bq2010 Gas Gauge solution for NiCd or
NiMH battery packs
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Battery information available over a single-wire
bidirectional serial port
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Battery state-of-charge monitoring for 4- to 12-cell
series applications
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On-board regulator allows direct connection to the
battery
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“L” version includes push-button activated LEDs to
display state-of-charge information
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Nominal capacity and cell chemistry pre-configured
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Compact size for battery pack integration
General Description
The bq2110 Gas Gauge Module provides a complete and
compact solution for capacity monitoring of NiCd and
NiMH battery packs. Designed for battery pack integration, the bq2110 incorporates a bq2010 Gas Gauge IC, a
current sense resistor, and all other components necessary to accurately monitor and display the capacity of 4
to 12 series cells. The bq2110L includes six surfacemounted LEDs to display remaining capacity in 20% increments of the learned capacity (relative mode) or pro
grammed capacity (absolute mode). The sixth LED is
used in absolute mode to represent an overfull condition
(charge above the programmed capacity). The LEDs are
activated with the onboard push-button switch.
Contacts are provided on the bq2110 for direct connec
tion to the battery stack (BAT+, BAT-), the serial com
munications port (DQ), and the empty indicator
(EMPTY). Please refer to the bq2010 data sheet for the
specifics on the operation of the Gas Gauge.
Unitrode configures the bq2110 based on the informa
tion requested in Table 1. The configuration defines the
number of series cells, the nominal battery pack capac
ity, the self-discharge rate, and the LED display mode.
A module development kit is also available for the
bq2110. The bq2110B-KT or bq2110LB-KT includes one
configured module and the following:
1) An interface board that allows connection to the serial port of an AT-compatible computer.
2) Menu-driven software with the bq2110 to display
charge/discharge activity and to allow user interface to the bq2010 from any standard DOS PC.
3) Source code for the TSR.
Pin Descriptions
P1
DQ/Serial communication port
P2
BAT+/Battery positive/pack positive
P3
No connect
P4
EMPTY/Empty indicator output
P5
GND/Ground
P6
PACK-/Pack negative
P7
BAT-/Battery negative
1
NiCd or NiMH Gas Gauge Module
bq2110
5/99 B