Features
ä
Complete bq2014 Gas Gauge solution for NiCd or
NiMH battery packs
ä
Charge-control output allows communication to
external charge controller (bq2004)
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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
ä Compact size for battery pack integration
General Description
The bq2114 Gas Gauge Module provides a complete and
compact solution for capacity monitoring of NiCd and
NiMH battery packs. Designed for battery pack integration, the bq2114 incorporates a bq2014 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 bq2114L includes five surfacemounted LEDs to display remaining capacity in 20% in
crements of the learned capacity (relative mode). The
LEDs are activated with the onboard push-button
switch.
Contacts are provided on the bq2114 for direct connec
tion to the battery stack (BAT+, BAT-), the serial com
munications port (DQ), the empty indicator (EMPTY),
and the charge control output (CHG). Please refer to the
bq2014 data sheet for the specifics on the operation of
the Gas Gauge.
Unitrode configures the bq2114 based on the informa
tion requested in Table 1. The configuration defines the
number of series cells, the nominal battery pack capac
ity, and the self-discharge rate.
A module development kit is also available for the
bq2114. The bq2114B-KT or bq2114LB-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 bq2114 to display
charge/discharge activity and to allow user interface to the bq2014 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
CHG/Charge control output
P4
EMPTY/Empty indicator output
P5
GND/Ground
P6
PACK-/Pack negative
P7
BAT-/Battery negative
1
NiCd or NiMH Gas Gauge Module
with Charge-Control Output
bq2114
5/99 B