Infineon introduces a new sensing and balancing IC for battery management systems in electric vehicles

     Infineon Technologies further expands its portfolio of products for battery management systems with the introduction of a new sensing and balancing IC (TLE9012AQU). The device is specifically designed for batteries in hybrid and electric vehicles, but is also suitable for other applications. It can measure the voltage of up to 12 cells, and over its lifetime, the device is capable of measuring accuracy up to ± 5.8 mV over the entire operating temperature and voltage range. Not only that, it can support up to five external temperature sensors, provide integrated battery cell balancing, and communicate using the iso-UART interface.

     The battery management system (BMS) ensures that the battery capacity is optimised, which means that electric vehicles can achieve a longer range and the battery does not age prematurely. In addition, they can determine the state of charge and health of the battery in order to estimate the range and predict the remaining service life of the battery. The TLE9012AQU provides the necessary measurement data and ensures a balanced charging state through battery cell balancing. The benefits are numerous, including avoiding the weakest cell limiting the total available capacity of the battery.

     To minimize the impact of interfering signals on measurement results, the new sensing and balancing IC from Infineon is equipped with a programmable noise filter. In addition, it can be measured in all cells at the same time, so that the measurement results are comparable despite temporary interference factors. The compensation algorithm based on integrated stress sensor and extended temperature compensation ensures the long-term stability of measurement.

     Battery cell balance is achieved through 12 balance switches integrated on the chip (one switch per channel). They are specifically designed to support a maximum current of 150 mA. In order to obtain higher balanced current, the device also supports external switches. In addition, the battery cell balance can be set to stop automatically after reaching a specified time (no more than 32 hours), or when the battery cell reaches a specified voltage, without the need for a microcontroller to send a signal. In this way, the microcontroller can be switched to sleep mode, thus saving energy.

     The TLE9012AQU has 12 channels and is particularly suitable for batteries where each module is divided into 12 cells. In this case, one device per module is sufficient. Data is exchanged between these modules and the microcontroller through an iso-UART interface, making voltage isolation easy and ensuring data integrity. This communication interface supports more than 20 series devices and ring topologies. This ensures that even if one component fails, the communication chain will not be broken and the rest of the system will still work normally.