STMicroelectronics L9965A/L99BM218 18-Cell Battery Management IC
STMicroelectronics L9965A/L99BM218 18-Cell Battery Management IC (BMIC) belongs to the L9965/L99BM2 chipset family for high-voltage battery management system monitoring and control (automotive/industrial, respectively). The L9965A/L99BM218 BMIC device provides all the functions needed to manage battery pack configurations up to 18s. It features a comprehensive set of cell/pack monitoring, balancing, and protection functions designed to achieve the highest FuSa targets in demanding systems (ASIL D for automotive applications).
The device uses dedicated high-precision ADCs that synchronously acquire cell, busbar, and pack voltages. The cell measurement ranges from -1V to 5.5V, making the L9965/L99BM2 family suitable for most battery chemistries. An arbitrary number of busbars can be monitored by each cell-voltage pair and by a dedicated BB channel.
The BMIC is supplied via an efficient buck pre-regulator, thus optimizing energy consumption and heat dissipation. It also integrates a 5V LDO available for biasing external sensors and supplying external EEPROMs. An SPI controller and an I2C controller enable interfacing with external sensors and EEPROMs. Passive balancing is available in both continuous and PWM mode.
Up to 59 addressable devices can be stacked in a vertical isolated communication interface. The STMicroelectronics L9965A implements an ultra-fast isolated communication protocol that allows transfer of voltage and temperature data for the entire daisy chain in less than 10ms.
Features
- –40°C to +125°C operating temperature range with temperature grade 1
- HBM ESD classification level 2
- CDM ESD classification level C4B
- Fully synchronized high-accuracy measurements on cell voltage, busbar, and stack voltage with dedicated ADC
- Total error including aging and post soldering < 1.4mV at 3.3V, -40°C to +105°C
- 16-bit resolution
- -1V to 5.5V cell range
- Integrated digital filtering with programmable cut-off frequency from 3.3kHz to 4.4Hz
- Fully redundant architecture
- Cell and busbar support on every channel
- Dedicated busbar channel with a ±1V range
- Passive internal cell balancing up to 400mA, supporting time-continuous and PWM modes
- Includes automatic cool-down based on external NTC sensing
- Overcurrent protection during balancing is also available in low-power mode
- Integrated DC-DC converter for energy efficiency
- < 12µA deep sleep
- < 20µA cyclic wake-up mode
- < 3mA normal mode
- Ten configurable GPIO
- SPI controller and I2C controller peripherals for interfacing external EEPROMs and sensors
- SPI target for direct MCU interface
- Stackable architecture for high-voltage battery packs up to 59 devices
- Embedded NVM for configuration parameter storage and runtime configuration integrity check
- Ultra-fast vertical interface peripheral for isolated communication
- Compatible with the L9965C pack monitoring chip with a max desynchronization time of 7µs at the system level
Applications
- Automotive battery monitoring systems
- Energy storage systems
- UPS
Additional Resources
Block Diagram
Development Tool
STMicroelectronics EVL9965A/EVL99BM218 Promotional Boards
Promotional boards for the L9965A/L99BM218 devices in battery management systems.
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STMicroelectronics Standard Products
A broad range of drop-in replacements for general-purpose analog ICs, discretes, and serial EEPROMs.