TIDUEM5 December   2018

 

  1.    Description
  2.    Resources
  3.    Features
  4.    Applications
  5.    Design Images
  6. 1System Description
    1. 1.1 Key System Specifications
    2. 1.2 Introduction
    3. 1.3 MSP430FR2633 CapTIvate MCU
  7. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
    3. 2.3 Highlighted Products
      1. 2.3.1 MSP430FR2633 MCU Block Diagram
      2. 2.3.2 CapTIvate Technology Block Diagram
  8. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 System Design Theory
    2. 3.2 Capacitive Touch Sensors
      1. 3.2.1 Wheel Sensor
      2. 3.2.2 Slider Sensor
      3. 3.2.3 Button Sensor
    3. 3.3 Gesture and Key Mapping
      1. 3.3.1 Media Player
      2. 3.3.2 USB HID Keyboard Data
    4. 3.4 Capacitive Touch Gestures
      1. 3.4.1 How Gesture Detection Works
      2. 3.4.2 Tap Gesture
      3. 3.4.3 Double-Tap Gesture
      4. 3.4.4 Tap-and-Hold Gesture
      5. 3.4.5 Swipe Gesture
      6. 3.4.6 Slide Gesture
    5. 3.5 Getting Started With Hardware
    6. 3.6 Getting Started With Firmware
      1. 3.6.1 Programming Target MCU
      2. 3.6.2 MSP430FR2633 CapTIvate Gesture Firmware
      3. 3.6.3 Memory Footprint
      4. 3.6.4 MSP430F5529 HID Keyboard Device Firmware
    7. 3.7 Testing
      1. 3.7.1 Gesture
      2. 3.7.2 Power Measurements
      3. 3.7.3 Moisture Tolerance
  9. 4Demonstration
    1. 4.1 Wheel
      1. 4.1.1 Volume Control
      2. 4.1.2 Changing Music Tracks
        1. 4.1.2.1 Play/Pause
      3. 4.1.3 Mute
    2. 4.2 Slider
      1. 4.2.1 Volume Control
      2. 4.2.2 Changing Music Tracks
      3. 4.2.3 Play or Pause
      4. 4.2.4 Mute
    3. 4.3 Buttons
      1. 4.3.1 Volume Control
      2. 4.3.2 Changing Music Tracks
      3. 4.3.3 Play or Pause
      4. 4.3.4 Mute
  10. 5Design Files
    1. 5.1 Schematic
    2. 5.2 Bill of Materials
  11. 6Software Files
  12. 7Related Documentation
    1. 7.1 Trademarks
  13. 8Terminology
  14. 9About the Author

3.7.2 Power Measurements

The MSP430FR2633 operates in Active mode while the user is touching any sensor on the CAPT-BSWP board. The measured current averages approximately 480 µA in this mode.

When the sensors are no longer being touched, the CPU enters low power mode LPM3 indefinitely and the CapTIvate peripheral is configured to operate in wake-on-proximity mode. In this mode, the CapTIvate peripheral is only looking for the presence of a finger or hand, waking the CPU if detected. Operating in this wake-on-proximity mode, the CPU can achieve very low power. The measured current averages approximately 5 µA in this mode.

Two methods are available to measure the MSP430FR2633 power consumption.

  1. Remove jumper J3 on the MSP430FR2633 MCU board and connect a current meter between jumper J3 "3.3V LDO" pin and J3 "MCU VCC" pin.
  2. Connect the CAPT-PGMR board and use the programmer’s Energy Trace™ feature to measure the current. Note, on the MSP430FR2633 MCU board, move jumper J3 between jumper J3 "MCU VCC" pin and J3 "3.3V Metered" pin.

For either option, return jumper J3 to the original position when done.

NOTE

The MSP430F5529 LaunchPad development kit must be disconnected from the MSP430FR2633 MCU board during the measurement. The MSP430FR2633 MCU board continues to respond normally to finger gestures.

For more information about current measurements on the MSP430FR2633, refer to the Experiments with Low Power section of the CapTIvate™ Technology Guide.

Test Conditions (Method 1) Result
Active mode 480 µA
Low power, Wake on Proximity 5 µA