BQ2018

The BQ2018 from Texas Instruments is a versatile charge/discharge counter designed for battery management applications. It supports multiple cell chemistries including Lead Acid, Li-Ion/Li-Polymer, NiCd, and NiMH, and is suitable for single-series cell configurations.

This IC features a high-speed 1-wire HDQ communication interface for efficient data transfer. It measures voltage drops across a sense resistor to accurately track charge and discharge cycles, providing essential state-of-charge information to a host controller. Key specifications include a battery capacity range from 1000 mAh to 4500 mAh and an operating temperature range of -20°C to 70°C.

The BQ2018 is available in compact 8-pin TSSOP and SOIC packages, allowing for easy integration into battery packs. It operates with low power consumption, featuring an operating mode current of less than 80µA and a sleep mode current of less than 10µA. The device also includes an internal temperature sensor for self-discharge estimation and 1024 bits of NVRAM for configuration.

Note that this product is in the process of being discontinued. Designers should consider alternate parts such as the BQ27Z561-R2 or BQ27Z746 for new designs.