Single-cell fuel gauge with on-chip fault protection
The BQ27Z746YAHR is a pack-side fuel gauge for single-cell Lithium Ion/Polymer batteries, using Impedance Track to report state-of-charge over I²C. It integrates over-current, over-temperature, over/under-voltage, and short-circuit fault protection — reducing the need for a separate supervisor IC on the battery pack PCB.
Package footprint and layout considerations
Housed in a 15-DSBGA measuring 1.7x2.6 mm, the BQ27Z746YAHR uses a 0.4 mm ball pitch. This BGA demands micro-vias and a fine-line PCB stack-up — a two-layer board will struggle to route all signals; plan for at least a four-layer design with via-in-pad if space is tight. CT is available for prototype or low-volume builds.
Active lifecycle — no LTB planning needed
There is no published end-of-life notice or last-time-buy window, so the part can be committed to a BOM without near-term obsolescence risk.