SLAAEF6 September   2023 MSPM0L1105 , MSPM0L1106 , MSPM0L1306 , MSPM0L1344 , MSPM0L1345 , MSPM0L1346

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1PIR Design Description
    1. 1.1 PIR Sensor
    2. 1.2 PIR Signal Chain
      1. 1.2.1 Traditional Motion Detection Signal Chain Design
      2. 1.2.2 Capacitor-Free Signal Chain Design
  5. 2Hardware and Schematic
    1. 2.1 MSPM0L1306
    2. 2.2 MSPM0 PIR Boosterpack
      1. 2.2.1 Schematic
  6. 3Software
    1. 3.1 Software Architecture
    2. 3.2 Software Flow Chart
    3. 3.3 Data Processing
      1. 3.3.1 Digital Signal Conditioning
      2. 3.3.2 Low-Pass Filter for Temperature Drift
      3. 3.3.3 Spikes and Noise
      4. 3.3.4 Motion Detection Function
  7. 4Results
    1. 4.1 Power Profile and Current Consumption
    2. 4.2 Detection Performance
      1. 4.2.1 Distance: 5 meters (16.4 ft)
      2. 4.2.2 Distance: 9 meters (29.5 ft)
      3. 4.2.3 Distance: 10 meters (32.8 ft)
  8. 5Summary
  9. 6References

3.2 Software Flow Chart

Figure 3-2 shows a flow chart of the software's overall behavior. The demo software wakes up and performs this full loop 20 times a second. The measurement takes approximately 90 μs and another 40-60 µs for simple data processing. The other 99.5% of the time, the analog is shut down and the MSPM0 is sleeping in Standby mode drawing ~1 uA. This flow chart is explained somewhat further in the power profile section.

GUID-F2064B29-D7FF-4F9B-A05B-16E3F139200D-low.png Figure 3-2 Software Flow Chart