SLAU857A May   2021  – July 2021 MSP430FR2476 , MSP430FR2512 , MSP430FR2522 , MSP430FR2532 , MSP430FR2533 , MSP430FR2632 , MSP430FR2633 , MSP430FR2672 , MSP430FR2673 , MSP430FR2675 , MSP430FR2676

 

  1.   1
  2.   2
    1.     3
    2.     4
  3.   5
    1.     6
    2.     7
    3.     8
  4.   9
    1.     10
      1.      11
      2.      12
      3.      13
    2.     14
    3.     15
  5.   16
    1.     17
      1.      18
      2.      19
        1.       20
        2.       21
        3.       22
      3.      23
    2.     24
      1.      25
      2.      26
  6.   27
    1.     28
      1.      29
      2.      30
      3.      31
      4.      32
      5.      33
    2.     34
      1.      35
      2.      36
      3.      37
    3.     38
    4.     39
      1.      40
      2.      41
      3.      42
      4.      43
      5.      44
    5.     45
    6.     46
      1.      47
      2.      48
      3.      49
      4.      50
      5.      51
  7.   52
    1.     53
    2.     54
    3.     55
    4.     56
    5.     57
  8.   58
  9.   59

5.4.3 Sensitivity Parameter Adjustment

The adjustment of the sensitivity parameter is mainly based on the actual detection requirements to select the appropriate system gain and the appropriate threshold. Increasing the gain of the CapTIvate system infinitely amplifies the noise while amplifying the touch signal. In the end, it only increases the resolution of the system, but the signal-to-noise ratio itself does not change. Because a larger gain increases the conversion time, it is not recommended to adjust the gain of the entire system too high. The functions involved in this part are shown in Table 5-6, and the numbers in the selection boxes correspond to those in Figure 5-13.

Table 5-6 Sensitivity Parameters
Number OperationFunction Recommended Value Comment
8 Conversion Count Set the equivalent setting value of the capacitance corresponding to the Sensor. <1000 Determine the system resolution.
Conversion Gain Set the system gain corresponding to the Sensor. 100 The minimum value is 100.
Frequency Divider Set the frequency division coefficient of charge sampling and conversion. Can use default value If the parasitic capacitance is too large, you need to grab the waveform to check whether the frequency division coefficient needs to be adjusted.
9 Prox Threshold Set proximity sensor threshold. Make Prox Threshold Percentage greater than the Minimum value The absolute change threshold of the touch signal, all elements share a proximity sensing threshold.
Touch Threshold Set touch threshold. Ensure priority triggering of proximity sensing threshold The threshold of the percentage change of the touch signal. At the same time, adjust to select "select all", all elements have their own touch thresholds.
Desired Resolution The resolution of the slider, scroll wheel or touch panel. <100 Excessive resolution is easily affected by noise.