What is draining the battery on the PineTime smartwatch?

Abstract: Power management is an important part when developing a smartwatch to meet user expectations of battery lifetime and functionality. To develop a good power management structure, measurements of the device is crucial to understand the behavior and power consumption of hardware and software. In this thesis, measurements have been made to hardware connected to the PineTime smartwatch to get knowledge of its behavior and power consumption. A structure for hardware and software was developed to enable the possibility to debug, flash, and perform measurements. The purpose of the measurements is to find possible areas of improvement that have the potential to lower the overall power consumption of the device. From the measurements, the st7789V display driver and the hardware design was detected to have a high power consumption. Bluetooth was also found to have an odd behavior in terms of power consumption. From these findings, suggestions on how to lower the power consumption are presented.