company blog about ST Battery Management：L99BM114 Multicell battery monitoring and balancing IC

ST Battery Management：L99BM114 Multicell battery monitoring and balancing IC

L99BM114 is a Li-ion battery monitoring and protecting chip for high-reliability industrial applications and energy storage systems. Up to 14 stacked battery cells can be monitored to meet the requirements of 48 V and higher voltage systems.
 

Each cell voltage is measured with high accuracy, as well as the current for the on-chip coulomb counting. The device can monitor up to 7 NTCs. The information is transmitted through SPI communication or isolated interface.
 

Up to 31 L99BM114 can be connected in a daisy chain and communicate with one host processor via the transformer or capacitive isolated interfaces, featuring high-speed, low EMI, long distance, and reliable data transmission. Passive balancing with programmable channel selection is offered in both normal and low power mode (silent balance).
 

The balancing can be terminated automatically based on internal timer interrupt. Nine GPIOs are integrated for external monitoring and control, up to 7 of them can be configured for pack temperature monitoring via NTC. The L99BM114 features a comprehensive set of fault detection and notification functions to meet system safety standard requirements.

Product Attributes of L99BM114

Features of L99BM114
4 to 14 series cells battery monitoring and balancing
64 V operating voltage
Supports busbar connection without altering cell results
Independent 16-bit voltage ADC for each channel with accuracy less than 2 mV
18-bit ADC current measurement with coulomb counter
Fully synchronized current and voltage samples
Intelligent diagnostic routine providing automatic failure validation. Redundant fault notification through both SPI Global Status Word (GSW) and the dedicated FAULT line
9 GPIOs, with up to 7 analog inputs for NTC sensing
Internal passive balancing up to 200 mA. Possibility to drive external balancing transistors
2.66 Mbps isolated serial communication or up to 5 MHz SPI
Two 5 V regulators supporting external load connection with 25 mA (VCOM) and 50 mA (VTREF) current capability
Embedded NVM for customer parameters storage
System safety ready
64-pin TQFP package

Application of L99BM114
48 V and high-voltage battery packs
Backup energy storage systems and UPS
E-bikes, e-scooters
Portable and semi-portable equipment

Pin Description of L99BM114