Measuring Bluetooth® Low Energy Power Consumption
By Sandeep Kamath & Joakim Lindh
Table of Contents
KEYWORDS .............................................................................................................................. 1
1 INTRODUCTION ............................................................................................................. 1
2 ABBREVIATIONS ........................................................................................................... 2
3 UNDERSTANDING POWER METRICS IN BLUETOOTH LOW ENERGY ................... 3
4 TEST SETUP .................................................................................................................. 4
4.1 SYSTEM OVERVIEW.................................................................................................... 4
4.2 HARDWARE MODIFICATIONS ....................................................................................... 5
4.3 EMBEDDED SOFTWARE MODIFICATIONS ...................................................................... 6
4.3.1 Remove Periodic Event ..................................................................................................... 6
4.3.2 Configure General-Purpose Input / Output (GPIO) Pins ................................................. 6
4.4 CENTRAL DEVICE AND BTOOL SETUP ......................................................................... 7
5 MEASUREMENT AND ANALYSIS ................................................................................ 8
5.1 CAPTURING A WAVEFORM DURING A CONNECTION EVENT ........................................... 8
5.2 DETERMINING VARIANCE IN THE LENGTH OF CONNECTION EVENTS ............................ 12
5.3 PERFORMING MEASUREMENTS FOR CONNECTION EVENTS ........................................ 12
5.4 PERFORMING MEASUREMENTS OF SLEEP CURRENT .................................................. 14
5.5 FORMULAS AND CALCULATIONS ................................................................................ 17
5.6 USING EXCEL SPREADSHEET FOR CALCULATIONS ..................................................... 18
GENERAL INFORMATION ..................................................................................................... 23
5.7 DOCUMENT HISTORY ............................................................................................... 23