Wearables and hearables are the target for a power chip from Maxim, whose wafer-scale package allows a sub-30mm2 solution, it claims.

On board the chip, called MAX77654, is a single-inductor triple-output buck-boost regulator that can provide outputs from 0.8V to 5.5V, two 100mA LDOs, a Li-ion-Li-poly charger, three GPIOs and a watchdog timer.

Quiescent power is 6μA operating, 0.3μA shut-down and <200nA in factory shipping mode.

This SIMO [single-inductor multiple-output] PMIC delivers three outputs with just one inductor at 91% efficiency,” according the company. “Additionally, this SIMO PMIC provides superior output voltage ripple performance of less than 20mVp-p for noise sensitive rails.

The dc-dc converter can deliver up to 500mA at 1.8V (±3% accurate) from a 3.7V input using the shared 1.5μH inductor – this is where >90% efficeincy  can be found. Minimum input voltage is 2.7V.

MAX77654-pmicThe charger power path allows separate input current limit and battery charge current settings, with a constant-current charge rate programmable between 7.5mA and 300mA, and input current limit programmable across 95mA to 475mA. Battery regulation voltage is programmable from 3.6V to 4.6V, and end-of-charge detection is variable down to 375nA. Its input withstands over-voltages up to 28V, and a thermistor input provides temperature monitoring.

The evaluation kit is MAX77654EVKIT#.