The Analog Devices DS2777G+ is a multi-function controller built for 2-cell lithium-ion/polymer battery packs. It handles charge and discharge monitoring, communicates over I²C to a host MCU, and integrates over-current and over-voltage fault protection. The part is aimed at portable equipment, power tools, medical devices, and backup-battery systems where the ambient stays between -20°C and 70°C — indoor or sheltered environments, not under-hood automotive or outdoor enclosures without climate control.
I²C interface and fault protection — what matters for the BOM
The I²C interface is the only host link on this controller. If your MCU does not have an I²C peripheral, you will need a bit-banged GPIO pair or an I²C bridge. The over-current and over-voltage fault protection is built in, which reduces external sense resistors and comparators — saves board area and BOM count. The protection thresholds are set internally; there is no external trim resistor for the trip points, so verify the default limits match your cell chemistry and charge profile.
14-TDFN with exposed pad, 3x5 mm body. Tube shipment, not tape-and-reel, so plan for manual placement or a tube feeder if your line is set up for reels.
No NRND or last-time-buy notice. No pin-compatible second source or official replacement has been published; if you need a cross, the closest functional sibling is another Analog Devices 2-cell Li-Ion controller with I²C, but the package and protection set differ — verify the full pinout before substituting.