SIMO Switching Regulators: Extending Battery Life for Hearables and Wearables

Used in hearables and wearables, single-inductor multiple-output (SIMO) switching regulators extend battery life by replacing multi-inductor and LDO-based power architectures with a compact, high-efficiency buck-boost design. This white paper from Maxim Integrated (now a part of Analog Devices) explains how SIMO technology time-multiplexes energy across multiple outputs, reduces component count, lowers quiescent current, and optimizes inductor utilization for space-constrained devices.

White Paper Overview

Used in hearables, wearables, and other ultra-compact battery-powered electronics, single-inductor multiple-output (SIMO) switching regulators enable longer battery life by consolidating multiple voltage rails into a single-inductor buck-boost architecture. This white paper from Maxim Integrated (now a part of Analog Devices) explores the limitations of traditional multi-inductor and LDO-based power trees and explains how SIMO regulators reduce component count, improve efficiency, and better utilize limited PCB space in small form-factor designs.

Download this white paper to learn how buck-boost SIMO architectures time-multiplex energy delivery across multiple outputs, support voltages above, below, or equal to the battery rail, and optimize peak inductor current for improved efficiency, reduced EMI, and lower power dissipation. Key design considerations include managing output ripple, selecting appropriate inductance and capacitance values, balancing peak current limits, and leveraging discontinuous conduction mode (DCM) operation.

The paper also highlights the MAX77650 and MAX77651 power management ICs, which integrate micropower SIMO converters with ultra-low quiescent current and an onboard LDO for noise-sensitive rails.