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

3.3 Door and Window Sensor

The Reed Switch is capable of detecting magnetic fields. Normally, the switch is open, but when a magnetic field is applied to the switch, the switch closes. The Reed Switch is connected in series with a pull-up resistor, thus, the REED signal can be active low. A reed switch can be used in numerous of applications; one example can be a door/window sensor. Figure 3-10 shows a detection of a door opening event.

Detection of a Door Opening Event Figure 3-10 Detection of a Door Opening Event

The detection distance with the first magnet is maximum at the center at approximately 0.7 inches, with two lobes on either side of the center peak. The darker shaded red areas indicate detection overlap in the Z axis which are clearly displayed in the following 3D figure:

Reed Switch Magnet 1 Detection Field (3D) Figure 3-11 Reed Switch Magnet 1 Detection Field (3D)