Multi-chemistry charge controller in a compact 8-TSSOP
The Texas Instruments BQ24400PWRG4 is a multi-chemistry battery charge controller IC designed for charging NiCd, NiMH, and lead-acid battery packs — the chemistry selection is set by external resistor dividers, not a firmware register. It operates from a supply voltage up to 6V and provides programmable charge termination via timer and voltage thresholds, making it suitable for portable instruments, backup power systems, and general-purpose battery-powered equipment where the microcontroller handles system supervision.
Programmable charge control without a host MCU
The BQ24400PWRG4 integrates programmable timer and voltage features that set charge termination thresholds and safety timeout periods — no I²C or SPI bus needed, just resistor-divider values on the appropriate pins. This standalone operation simplifies the BOM for cost-sensitive designs: a single charge controller handles the charge algorithm while the system MCU (if present) only monitors battery status through a GPIO.
Temperature range and package for indoor and portable gear
The 8-TSSOP package (0.173" body width, 4.40 mm wide) with Surface Mount mounting allows placement on compact two-layer PCBs; the 0.65 mm lead pitch is compatible with standard fine-pitch soldering profiles.