FEATURES
➤ Conservative and repeatable measurement of available charge in rechargeable batteries ➤ Designed for portable equipment such as power tools with high discharge rates ➤ Designed for battery pack integration - 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 ➤ Self-discharge compensation using internal temperature sensor ➤ Simple single-wire serial communications port for subassembly testing ➤ 16-pin narrow SOIC GENERAL DESCRIPTION
Battery self-discharge is estimated based on an internal timer and temperature sensor. Compensations for battery temperature and rate of charge or discharge are applied to the charge, discharge, and selfdischarge calculations to provide available charge information across a wide range of operating conditions. Initial battery capacity is set using the PFC and MODE pins. Actual battery capacity is automatically “learned” in the course of a discharge cycle from full to empty and may be displayed depending on the display mode.
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