Maxim Integrated Products MAX20345 ultralow-power PMIC

Designers of always-on wearable and Internet of Things (IoT) devices now have an easy way to extend battery runtime while shrinking form factor with a tiny, highly integrated power-management IC (PMIC) from Maxim Integrated Products. The ultralow-power MAX20345 integrates a lithium charger and features an architecture that optimises the sensitivity of optical measurements for wearable fitness and health applications.

The product features a buck-boost regulator based on an innovative architecture that’s optimised for heart-rate, blood-oxygen (SpO₂) and other optical measurements. The regulator delivers the desired low-quiescent-current performance without the drawbacks that degrade signal-to-noise ratio (SNR) and, as a result, is said to increase performance by up to 7 dB (depending on measurement conditions).

In order to raise efficiency without sacrificing battery runtime, the device integrates a lithium-ion battery charger; six voltage regulators, each with ultralow quiescent current; three nanoPower bucks (900 nA typical); and three LDO regulators with ultralow quiescent current (as low as 550 nA typical). Two load switches allow disconnecting of system peripherals to minimise battery drain. Both the buck-boost and the bucks support dynamic voltage scaling (DVS), providing additional power-saving opportunities when lower voltages can be deployed under favourable conditions.

The system is available in a 56-bump, 0.4 mm pitch, 3.37 x 3.05 mm wafer-level package (WLP), providing a sophisticated power architecture for space-constrained wearable and IoT designs.