Maxim extends battery life for medical wearables

  • November 16, 2021
  • Steve Rogerson

Maxim Integrated, now part of Massachusetts-based Analog Devices, has introduced a battery management IC to enable longer run-time for medical and fitness wearables.

The Max 17330 has an integrated fuel gauge and battery protection for one-cell lithium-ion and polymer batteries that is said to deliver longer battery runtime for consumer applications than similar products.

The IC expands Maxim’s battery management portfolio, which already delivers accuracy for the automotive and industrial markets. Compared with similar products, the Max 17330 is said to extend run-time significantly and monitor internal cell self-discharge hazards, while also shrinking size of single cell battery-powered products.

The company’s proprietary AccuCharge and ModelGauge technologies deliver high top-off charge and deep safe discharge, enabling longer run-time of medical and fitness wearables, as well as home and building automation sensors, handheld computers and terminals. It also simplifies battery management for devices using parallel cells, such as foldable smartphones and tablets, as well as AR and VR smart glasses.

Conventional battery charger ICs implement techniques that result in inconsistent charging and, consequently, require an additional margin for the battery protector. This limits the battery from being charged to its maximum level. Many modern devices require multiple cells that are separated physically to manage the weight distribution for good ergonomics or user experience. This poses challenges while charging, as the batteries can have unequal impedances and can also be of different capacities and initial states.

The Max 17330 addresses these difficulties by controlling the charger using its integrated fuel gauge for each individual cell.

AccuCharge is said to provide 20 per cent more accurate charging. The ModelGauge M5 fuel gauge algorithm is said to deliver 40 per cent more accurate state-of-charge (SoC) readings; EZ configuration eliminates any need for battery characterisation.

Small wafer level package (WLP) and integration of the battery charger, fuel gauge, protector and authenticator functions can reduce the total size by 36 per cent compared with similar products.

Analog Devices serves 125,000 customers worldwide with more than 75,000 products in the industrial, communications, automotive and consumer markets. It is headquartered in Wilmington, Massachusetts.