SPRADL9 February   2025 CC1310

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
    1. 1.1 Sensor Controller in Building Automation
    2. 1.2 TI Devices
      1. 1.2.1 CC13x4 Wireless MCUs
      2. 1.2.2 CC26xx Wireless MCUs
  5. 2Sensor Controller
    1. 2.1 Features
    2. 2.2 Sensor Controller Power Modes
      1. 2.2.1 Active Mode
      2. 2.2.2 Low Power Mode
      3. 2.2.3 Standby Mode
      4. 2.2.4 Switching Between Power Modes
        1. 2.2.4.1 24MHz - Startup From Standby and Return to Standby Energy
        2. 2.2.4.2 2MHz - Startup From Standby and Return to Standby Energy
    3. 2.3 Power Measurement Setup
      1. 2.3.1 EnergyTrace™ Software
      2. 2.3.2 Software
      3. 2.3.3 Current Consumption Measurements
      4. 2.3.4 Hardware
  6. 3Building Automation Use-Cases and Techniques using Sensor Controller
    1. 3.1 PIR Motion Detection
      1. 3.1.1 PIR Traditional Signal-Chain
      2. 3.1.2 Capacitor-less Motion Detection Block Diagram
      3. 3.1.3 Digital Signal Processing
        1. 3.1.3.1 Hardware
        2. 3.1.3.2 Digital Signal Processing
    2. 3.2 Glass Break Detection
      1. 3.2.1 Low-Powered and Low-Cost Glass Break Block Diagram
    3. 3.3 Door and Window Sensor
    4. 3.4 Low-Power ADC
      1. 3.4.1 Code Implementation in Sensor Controller Studio
      2. 3.4.2 Measurements
    5. 3.5 Different Sensor Readings with BOOSTXL-ULPSENSE
      1. 3.5.1 Capacitive Touch
      2. 3.5.2 Analog Light Sensor
      3. 3.5.3 Potentiometer (0 to 200kΩ range)
      4. 3.5.4 Ultra-Low Power SPI Accelerometer
      5. 3.5.5 Reed Switch
  7. 4Summary
  8. 5References

3.5.2 Analog Light Sensor

Analog light sensors play a crucial role in building automation applications by providing real-time data on ambient light levels and thus enabling dynamic control of lighting systems and other environmental settings. One example can be in lighting automation where artificial light is adjusted based on the amount of natural light available (daylight harvesting). In HVAC systems, analog light sensors work alongside other sensors to detect sunlight intensity and adjust heating or cooling systems accordingly depending on the season and daytime.

The Analog Light Sensor outputs a current dependent on the amount of light the Sensor is exposed to. The current is fed into a resistor creating a voltage which can be captured by the ADC. The Sensor Controller uses the peripheral Timer 2 to enable power to the analog light sensor around 1ms before the Sensor Controller can wake up to take a measurement. If the light level is higher than a threshold, the Sensor Controller can wake up the System CPU for processing of the measurement. This can repeat with a frequency of 10Hz. The example is tested with the same ambient light during the whole test period.

Table 3-4 Analog Light Sensor Power Consumption
Average current consumptionUnitBattery life (CR123)
Analog light sensor (10Hz)9.1µA2years and 6 months
Analog Light Sensor: 30 SecondsFigure 3-18 Analog Light Sensor: 30 Seconds
Analog Light Sensor: 2 SecondsFigure 3-19 Analog Light Sensor: 2 Seconds
Analog Light Sensor: One MeasurementFigure 3-20 Analog Light Sensor: One Measurement