Low Voltage Fuel Gauge

The ISL6295 is a cost-effective, highly accurate IC that measures, stores, and reports all of the critical parameters required for rechargeable battery monitoring with a minimum of external components. It precisely measures charge/discharge current as well as voltage and temperature of a battery pack. In addition, the ISL6295 accurately accumulates both charge and discharge current as independent parameters. Temperature history can also be maintained for calculating self-discharge effects.

Features

• Measures, maintains, and reports all critical rechargeable battery parameters with high accuracy

• Supports Lithium Ion and Lithium Polymer battery packs

• Current measurement with 16-bit (15-bit plus sign) integrating A/D accurate to less than ±0.5 error

• Calibrated temperature measurement accurate to within ±3°C absolute using on-chip temp sensor or external thermistor

• Accumulation of charge current, discharge current, temperature, and voltage in independent 32-bit registers

• 256-byte nonvolatile EEPROM stores factory programmed, measured, and user-defined parameters

• In-system offset calibration compensates for offset error in current measurement

• Industry standard SMBus/I2C™ compatible 2-wire communications interface

- SMBus V1.1 with PEC/CRC-8 communication

• -20°C to +85°C operating temperature range

• NTC pin can be configured as a thermistor input or GPIO

• GPAD pin can be configured as an independent A/D input or GPIO

• Flexible power operating modes allow low-power monitoring of battery conditions during system full operating and standby conditions:

- Run: Continuous Conversion; 85µA typ.

- Sample: Sample interval from 0.5-64s @ 45µA typ.

- Sample-Sleep: Sample interval from 0.5-138s min. @20µA typ.

• Shelf-Sleep mode reduces power consumption to pack storage conditions to 300nA typ., with automatic wake-up upon pack insertion.

Applications

• Notebook PC, PDAs, Hand Held Devices