Programmable ICs Simplify Design Of Battery Fuel Gauge

Two new families of programmable, smart battery ICs have been developed for use with all battery chemistries. The P4 chip family employs 6 Kbytes of integral flash EEPROM to hold battery control algorithms, cell chemistry performance models, and associated equations for battery capacity calculations. The flash block also contains battery pack calibration information and all learned and historical data. The P3 chip family, by contrast, uses external EEPROMs of various sizes and densities for storing programmable battery parameters and algorithm variables. Said to provide the industry's highest fuel gauging accuracy, the chips' self-calibrating 14-bit A/D converter is said to measure remaining battery capacity to within ±1%. Both series of devices come packaged in 28-pin, 209-mil SSOPs.