BQ25798

The BQ25798 is a highly integrated battery charger IC designed for portable and wearable devices, featuring a high-efficiency buck-boost converter that supports charging from a wide input voltage range of 3.0 V to 24 V. It enables fast charging of single-cell lithium-ion or lithium-polymer batteries with programmable charge current up to 3 A and voltage up to 4.4 V. The device operates in either constant-current (CC) or constant-voltage (CV) mode, ensuring precise battery management and protection against overcharge. It includes an integrated power path management system that allows the device to operate directly from the input source while charging the battery, eliminating brownout conditions during high-load events. This feature is particularly beneficial for applications like smartwatches, wireless earbuds, and medical wearables where uninterrupted operation is critical. The BQ25798 also features adaptive voltage positioning (AVP), which dynamically adjusts the output voltage based on load current to improve efficiency and reduce power loss. Thermal regulation is handled through a temperature-compensated charge current control mechanism, preventing overheating during high-power charging scenarios. Additionally, the IC offers comprehensive protection features including overvoltage, overcurrent, short-circuit, thermal shutdown, and battery safety monitoring. Its built-in fuel gauge interface supports external fuel gauges for accurate state-of-charge estimation, enhancing user experience in battery-powered systems. The BQ25798 integrates a low-dropout regulator (LDO) to provide a stable 3.3 V supply for system components, reducing the need for external regulators. It supports both USB Type-C and legacy USB PD protocols via a configurable I²C interface, enabling flexible communication and configuration. The device is optimized for space-constrained designs with a compact 4 mm × 4 mm QFN package and requires minimal external components, simplifying PCB layout and lowering overall system cost. Designed for high reliability and robust performance, the BQ25798 operates across a wide operating temperature range from -40°C to +85°C, making it suitable for industrial and consumer applications alike. Its advanced power management architecture ensures efficient energy utilization, extending battery life and improving device longevity.