Power management for a multi-developer Zephyr environment

Abstract

Battery powered portable embedded devices that are limited in memory, size, and price, have been facing a significant gap between processing power and battery capacity. To diminish this gap, rigorous hardware and software power saving techniques must be implemented. The purpose of this thesis was to optimize the hardware design of a product under development by finding and repairing design flaws that caused excess power consumption. Additionally, this work aimed to implement and customize the power management framework provided by the real time operating system used in this product which is Zephyr. With this framework implementation, power management is completely carried out by the operating system, in other words, application developers who are known not to be fully cognizant of hardware design, schematics, and component data sheets, are not obliged to perform power management in their applications.

Initially, design flaws were repaired and all chips on the device under test were turned off by the software. The remaining excess current consumption was then approached by desoldering components from the board. The experimental results suggest a drastic decrease in power consumption in which the expected battery runtime increased from 30 minutes up to approximately one month of running a motion detection application.