5 Summary

This application note shows an ultra-low power optimized design by leveraging the Sensor Controller Engine (SCE) in the CC1352P MCU for reading out the HDC2010 humidity and temperature sensor. Multiple options were tested, including HDC2010 readouts every 10 s and every 60 s, the latter is compared to the nano-timer based Duty-cycling solution described in the TIDA-00484 design. Alternatively, a StandBy solution with sensor readout by the Arm Cortex-M4F MCU instead of SCE was developed and tested. By comparing the advantages and disadvantages of the three system solutions a decision tree for selecting the most efficient ultra-low power architecture was derived.

Knowing the length of the inactivity period (or sensor readout frequency) and the RF parameters and the RF protocol overhead, the application designer has guidance on how to select the lowest power system architecture.

The newly introduced Sensor Controller Engine solution is proven to perform equal or better than the standard StandBy approach, where the MCU is used to read out the sensor.

Duty-cycling is highly recommended for long inactivity application periods of typically many minutes or even hours, where a nano-timer device and load switch deliver the best power efficiency.

Designers must adapt the considerations in this report to their application profile and wireless protocol parameters.