Single inductor multi-output regulator and charger optimized for small Li-ion batteries

Designers of Bluetooth headphones, activity monitors, smart garments, smartwatches, and other size-constrained devices can now increase battery life and efficiency using the MAX77650 and MAX77651 PMICs from Maxim Integrated Products. Size is critical for hearables and wearables as they continue moving to smaller form factors. Most PMICs for these small, lithium-ion battery-operated devices require additional components, such as boost, buck, and LDO regulators; a charger; and current regulators for LED indicators. For space-savings and efficiency, the company has integrated all these functions into a complete power solution that is only 19.2mm-squared – less than 1/2 the size of existing component combinations. The devices feature SIMO buck-boost regulators that provide three independently programmable power rails from a single inductor, 150mA LDO, and three current sink drivers to reduce overall component count and maximize available board space. For design flexibility, the MAX77650 operates up to 3.3V and the MAX77651 operates up to 5V – both include an analog multiplexer (MUX) output for safe battery monitoring, making them ideal for low-power designs.