Infineon Technologies released the TLE9012AQU sensing and balancing IC, especially designed for batteries in hybrid and electric cars, but is also suitable for other applications. It measures the voltage in up to twelve battery cells with an accuracy of ± 5.8 mV over the entire temperature and voltage range, as well as the operating life cycle. It also supports up to five external temperature sensors, provides an integrated cell balancing function, and uses an iso-UART interface for communication.
The TLE9012AQU provides the necessary measurement data and ensures a balanced state of charge through cell balancing. Among other things, this prevents the weakest cell from determining the total usable capacity of the battery.
Features include a programmable noise filter. In addition, it performs the measurement in all cells simultaneously so that the results remain comparable even in the presence of temporary interference factors. A compensation algorithm with integrated stress sensor and extended temperature compensation ensures the long-term stability of the measurements.
Cell balancing is achieved via twelve balancing switches integrated on the chip – one per channel. They are designed for currents up to 150 mA. For higher balancing currents, the device also supports external switches. In addition, the cell balancing can be programmed to stop without a signal from the microcontroller after a defined time of up to 32 hours or when the cell has reached a defined voltage. This allows the microcontroller to switch to sleep mode and thus save energy.
Particularly suitable for batteries that are partitioned with twelve cells per module. One device is then required per module. The iso-UART interface for data exchange between these modules and with the microcontroller allows easy voltage isolation and ensures data integrity. The communication supports more than 20 serially connected devices and a ring topology, ensuring that even if a single device fails, the communication chain is not broken and the rest of the system remains functional.
In addition to the TLE9012AQU, Infineon is launching a matching iso-UART transceiver component (TLE9015QU). Both devices will be available in July 2020.
Further information is available at www.infineon.com
