BQ2010 Datasheet | UNITRODE

Not Remended For New Designs bq2010 Gas Gauge IC Features - Conservative and repeatable measurement of available charge in rechargeable batteries - Designed for battery pack integration - 120µA typical standby current - Small size enables imple- mentations in as little as 1 2 square inch of PCB - Integrate within a system or as a stand-alone device - Display capacity via single- wire serial munication port or direct drive of LEDs - Measurements pensated for current and temperature - Self-discharge pensation using internal temperature sensor - Accurate measurements across a wide range of current (> 500:1) - 16-pin narrow SOIC General Description The bq2010 Gas Gauge IC is intended for battery-pack or in-system installation to maintain an accurate record of a battery's available charge. The IC monitors a voltage drop across a sense resistor connected in series between the negative battery terminal and ground to determine charge and discharge activity of the battery. Ni MH and Ni Cd battery self-discharge is estimated based on an internal timer and temperature sensor. pensations for battery temperature and rate of charge or discharge are applied to the charge, discharge, and self-discharge calculations to provide available charge information across a wide range of operating conditions. Battery capacity is automatically recalibrated, or “learned,” in the course of a discharge cycle from full to empty. Nominal available charge may be directly indicated using a five- or six-segment LED display. These segments are used to indicate graphically the nominal available charge. The bq2010 supports a simple single-line bidirectional serial link to an external processor (mon ground). The bq2010 outputs battery information in response to external mands over the serial link. The bq2010 may operate directly from 3 or 4 cells. With the REF output and an external transistor, a simple, inexpensive regulator can be built to provide VCC across a...