15 Cell Lithium Ion Battery Controller Analog Front End Reference Design
TIDA-00255: The TIDA00255 reference design utilizes the bq76940 analog front end (AFE) IC. It measures cell voltages, and die temperature or external thermistor voltage using a 14 bit ADC. Current is measured separately by a separate 16 bit coulomb counter. The design can turn off low side power FETs to stop discharge or charge based on selected hardware limits. A microcontroller not included in this design would be part of the battery controller to communicate to the AFE to set protection thresholds, turn on the power FETs, provide fault recovery and turn off the FETs for over or under temperature conditions. A battery controller design may contain other features which are not part of this reference design such as secondary over voltage protection, gauging, and isolated communication to let the system know the state of the battery.
