The bq26500, the first in the bqJUNIOR family of advanced gas gauge device for handheld applications, is a highly accurate standalone single-cell Li-Ion and Li-Pol battery capacity monitoring and reporting device targeted at space limited portable applications. The device monitors a voltage drop across a small current sense resistor connected in series with the battery to determine charge and discharge activity of the battery. Compensations for battery temperature, self-discharge, and rate of discharge are applied to the charge counter to provide available capacity 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. Internal registers include available capacity, cell temperature and voltage, state-of-charge, and status and control registers.
The bq26500 can operate directly from single-cell Li-Ion and Li-Pol batteries and communicates to the system over a simple one-wire bi-directional serial interface. The 5-kbits/s HDQ bus interface reduces communication overhead in the external microcontroller.
Feature
- Reports Accurate State-of-Charge in Li-Ion and Li-Pol Cells, No System Processor Calculations Needed
- Reports Cell Temperature and Voltage
- High-Accuracy Coulometric Charge and Discharge Current Integration with Automatic Offset Cancellation
- Requires No Offset Calibration
- Programmable Input/Output Port
- Internal Time-Base Eliminates External Crystal Oscillator
- Four Automatic Low-Power Operating Modes
- Active: < 100 μA
- Sleep: < 2.5 μA
- Ship: < 1.7 μA
- Hibernate: < 1.5 μA
- Small 8-Pin TSSOP Package
- APPLICATIONS
- PDAs
- Smart Phones
- MP3 Players
- Digital Cameras
- Internet Appliances
- Handheld Devices