BQ2004

The BQ2004 Fast Charge IC from Texas Instruments provides advanced control for charging nickel-cadmium and nickel-metal hydride batteries. It integrates high-speed switching power control circuitry on a monolithic CMOS device, enabling cost-effective solutions for both stand-alone and system-integrated chargers.

Key features include hysteretic PWM switch-mode current regulation or gated control of an external regulator, allowing for flexible design implementations. The device supports pre-charge qualification of temperature and voltage, ensuring battery safety before charging begins. Fast-charge termination can be achieved through various methods, including temperature/time delta, peak voltage detection, negative delta voltage, maximum voltage, maximum temperature, and maximum time.

For enhanced battery conditioning and capacity determination, the BQ2004 supports switch-activated discharge-before-charge. It also offers optional top-off charge and pulsed current maintenance charging phases. The IC is configurable with direct LED outputs to display battery and charge status. It operates within an input voltage range of 4.5V to 5.5V and supports a maximum charge current of 2A. The device is available in 16-pin Narrow DIP or Narrow SOIC packages and operates across a temperature range of -20°C to 70°C.

With its logic-level controlled low-power mode, the BQ2004 consumes less than 5µA in standby, making it suitable for power-sensitive applications. This IC is easily integrated into systems or used as a stand-alone charger for batteries with one or more cells.