Texas Instruments BQ21062, 1-Cell Linear Charger IC

Texas Instruments BQ21062 1-Cell Linear Charger IC is a highly integrated battery charge management IC that integrates the most common functions for wearable, portable and small medical devices. These functions include a charger, a regulated output voltage rail for system power, a Load Switch/LDO, and a push-button controller. The Texas Instruments BQ21062 IC integrates a linear charger with Power Path that enables quick and accurate charging for small batteries while providing a regulated voltage to the system. The regulated system voltage (PMID) output may be configured through I2C based on the recommended operating condition of downstream IC’s and system loads for optimal system operation. The device supports a charge current up to 500mA and supports termination current down to 0.5mA for maximum charge. The battery is charged using a standard Li-Ion charge profile with three phases: pre-charge, constant current, and constant voltage regulation. The device integrates advanced Power Path management and control that allows the device to provide power to the system while charging the battery even with poor adapters. The host may also control the Power Path through I2C, allowing it to disconnect the input adapter and/or battery without physically removing them. The single push-button input eliminates the need for a separate button controller IC reducing the total solution footprint. The push-button input can be used for wake functions or to reset the system. The low quiescent current during operation and shutdown enables maximum battery life. The input current limit, charge current, LDO output voltage, and other parameters are programmable through the I2C interface making the BQ21062 a very flexible charging solution. A voltage-based JEITA compatible (or standard HOT/COLD) battery pack thermistor monitoring input (TS) is included that monitors battery temperature and automatically changes charge parameters to prevent the battery from charging outside of its safe temperature range. The temperature thresholds are also programmable through I2C, which allows the host to customize the thermal charging profile. The charger is optimized for 5V USB input, with 20V absolute maximum tolerance to withstand line transients. The device also integrates a linear regulator to provide a quiet rail for radios or processors and can be independently sourced and controlled through I2C.