SLUSFQ1A December 2024 – December 2024 BQ41Z90
ADVANCE INFORMATION
Refer to the PDF data sheet for device specific package drawings
The BQ41Z90 battery pack manager is a highly integrated device that employs flash-based firmware and integrated hardware protection to provide a complete solution for battery stack architectures with 3 to 16 series cells in series. The BQ41Z90 device utilizes Dynamic Z-Track™ technology to report highly accurate state of charge even under dynamic loading conditions. This technology is the extension of TI's renowned Impedance Track™ gauging algorithm which tracks the changing impedance over the lifetime of the battery to provide accurate full charge capacity (FCC), state of charge (SoC), and state of health (SoH) estimations.
The BQ41Z90 device supports systems with FETs in a series configuration as well as systems with parallel charging and discharging paths to accommodate different magnitudes of charging current vs. discharging current. In parallel configuration the device can connect to the charger connector while discharging through the load connection. The device also support systems that only use one FET or no FETs, replacing the FETs with external protectors.
The BQ41Z90 device provides Elliptic Curve Cryptographic (ECC) authentication capability to boost the battery pack security in addition to the SHA-1 and SHA-2 authentication options. The ECC authentication uses unique asymmetrical private/public key cryptography, eliminating the requirement of sharing the same secret in the host system.
The BQ41Z90 device provides hardware comparators to detect fault conditions due to over-voltage, over-temperature, short circuit detection, and over-current under charge and discharge, as well as the hardware drivers to turn off the FETs to protect the device from these fault conditions. The device firmware provides software-based 1st- and 2nd-level safety alerts and protection against over-voltage, under-voltage, over-current, short circuit current, and over-temperature conditions, as well as other fault conditions such as hardware watchdog timed-out or cell charge/voltage imbalance.
The BQ41Z90 battery pack manager interfaces with a host system through an SBS v3.2 compliant SMBus interface or an I2C-compliant interface, and processes instructions and data using a state-of-the-art, ultra-low-power 32-bit RISC processor. High-performance integrated peripherals enable support for a sense resistor down to 0.25mΩ, with simultaneous current/voltage data conversion for instant power calculations.
The following sections detail all of the major component blocks included as part of the BQ41Z90 Battery Manager.