Maxim Integrated has launched the industry’s first multi-cell fuel gauge with continuous internal self-discharge monitoring
The MAX17320 is a pack-side fuel gauge and protector IC for 2 to 4 series Lithium-ion (Li+) cells (2S-4S) and is part of a family of ICs equipped with Maxim’s patented ModelGauge m5 EZ algorithm that delivers 40 percent more accurate state-of-charge (SOC) readings than competitive offerings, eliminating the need for battery characterization for most common Li+ cells.
The fuel gauge also has a quiescent current (I Q) of 38µA, 85 percent lower than the nearest competitor, for hand-held devices with 2S-4S Li+ batteries in the computing, internet of things (IoT), power tool, consumer, healthcare and mobile device categories. Damaged or defective batteries may develop an internal cell leakage which can progressively get worse and can result in dangerous outcomes, including fire or explosion.
Stringent factory screening may prevent leaky cells from getting shipped out of the factory but there haven’t been ways to detect self-discharge that develops during normal usage of the battery. The MAX17320 warns the system and disables a leaky battery before a potentially hazardous outcome. This is in addition to the most advanced battery protection that uniquely allows fine tuning of voltage and current thresholds based on various temperature zones. The IC also provides a secondary protection scheme that permanently disables the battery by assisting a secondary protector or blowing a fuse in severe fault conditions.
The fuel gauge also has SHA-256 authentication to safeguard systems from counterfeit batteries that can also cause safety problems.
As with any mobile device, manufacturers aim to deliver products that have longer battery life than the competition. Devices also need to have accurate SOC information to determine the remaining run-time. The gauge allows designers to enable the longest run-time and avoid premature or sudden shutdown, while delivering the most accurate SOC in the industry.
The MAX17320 can run in an ultra-low-power mode, enabling the system