• Single-Cell Li-Ion Battery Fuel Gauge

• Resides on System Board

• Supports Embedded or Removable Batteries

• Powered Directly from Battery with Integrated LDO

• Easy To Configure Fuel Gauging Based on the Dynamic Voltage Correlation Algorithm

• Reports Remaining Capacity and State of Charge (SOC) with Smoothing Filter

• Automatically Adjusts for Self-Discharge, Temperature, and Rate Changes

• Microcontroller Peripheral Supports:

• 400-kHz I2C Serial Interface

• Configurable SOC Interrupt or Battery Low Digital Output Warning

• Internal Temperature Sensor or Host Reported Temperature

• Support 4.2-V, 4.3-V, and 4.35-V Chemistries

• 9-pin 1.62 × 1.58 mm, 0.5 mm pitch YZF package

The Texas Instruments bq27621-G1 is a minimally configured microcontroller peripheral that provides system-side fuel gauging for single-cell Li-Ion batteries. The device requires very little user configuration and system microcontroller firmware development.

The bq27621-G1 uses the Dynamic Voltage Correlation algorithm for fuel gauging. This process eliminates the need for a sense resistor when calculating remaining battery capacity (mAh), state-of-charge (%), battery voltage (mV), and temperature (°C).

Battery fuel gauging with the bq27621-G1 requires connections only to PACK+ (P+) and PACK– (P–) for a removable battery pack or embedded battery circuit. The tiny 9-pin, 1.62 mm × 1.58 mm, 0.5 mm pitch YZF package is ideal for space-constrained applications.