What this gas gauge does and where it fits
The Texas Instruments BQ2084DBT-V143 is a battery monitor IC — a gas gauge — designed to work alongside the BQ29312 analog front-end for Li-ion and Li-polymer battery packs. It communicates over SMBus, reporting remaining capacity, voltage, and temperature data to a host controller. The part monitors 2 to 4 series cells, making it a fit for notebook, portable instrument, and medical-device battery packs where the host needs accurate state-of-charge information without running its own coulomb-counting algorithm.
Integration note: pairing with the BQ29312
The BQ2084DBT-V143 is described as a gas gauge for the BQ29312. In a typical design, the BQ29312 handles cell balancing, overvoltage/undervoltage protection, and the primary analog measurement path, while the BQ2084DBT-V143 runs the fuel-gauging algorithm and communicates over SMBus. The two parts share a common I²C-like bus and a set of control signals. If you are replacing a failed gauge on an existing BQ29312-based board, this part is the intended mate. For a new design, verify that the BQ29312 is still available and that the combined BOM cost fits your target.