SLUUCG7 April 2024 BQ76922
The BQ76922 device is a highly integrated, accurate battery monitor and protector for 3-series to 5-series Li-ion, Li-polymer, and LiFePO4 battery packs. High accuracy voltage, current, and temperature measurements provide data for host-based algorithms and control. A feature-rich and highly configurable protection subsystem provides a wide set of protections, which can be triggered and recovered completely autonomously by the device or under full control of a host processor. The integrated charge pump with high-side protection NFET drivers enables host communication with the device even when FETs are off by preserving the ground connection to the pack. An LDO is included for external system use, programmable to voltages of 1.8V, 2.5V, 3.0V, 3.3V, or 5.0V, capable of providing up to 45 mA.
The BQ76922 device includes one-time-programmable (OTP) memory for customers to setup device operation on their own production line. Multiple communications interfaces are supported, including 400kHz I2C and HDQ one-wire standards. Multiple digital control and status data are available through several multifunction pins on the device, including an interrupt to the host processor, and independent controls for host override of each high-side protection NFET. Two dedicated pins are provided for temperature measurement using external thermistors, and multifunction pins can be programmed to use for additional thermistors, supporting a total of up to five thermistors, in addition to an internal die temperature measurement. Figure 2-1 shows the BQ76922 block diagram.