Cypress CapSense CY3280-SmartSense, Руководство к набору

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18 CY3280-SmartSense CapSense Auto-Tuning Kit Guide, Doc. # 001-64672 Rev. *B
Load CapSense Example Projects
3.1.4 Run Project
Power the board using any one of the sources listed in 2.1.3 Power Sources on page 11 . Touch a
CapSense button on the board to see the corresponding LEDs toggle, as shown in . Figure 3-6 .
Figure 3-6. Toggle Feature Test Sequence
3.1.5 Manual Tuning Limitations Demonstration
1. Power the board using one of the sources listed in 2.1.3 Power Sources on page 11
2. Touch BTN2 ; the corresponding LED2 toggles
3. Connect the supplied axial capacitor of 10 pF value between J5.5 and J5.2 (this adds to the par-
asitic capacitance of BTN2); see Figure 3-7
4. Toggle the board power
5. Touch BTN2 ; the BTN2-LED2 link is broken. This failure occurs due to manual tuning, see
Figure 3-8
6. Repeat step 2, 3, and 4 with 22 pF, 33 pF, and 68 pF axial capacitors
This experiment demonstrates that sensors need to be tuned to work every time its parasitic capaci-
tor value changes.
1. Touch a button; LED
turns on 2. Release the button; LED
remains on 3. Touch the same button
again; LED turns off
4. Release the button; LED
remains off 5. Touch the same button
again; LED turns on
6. Release the button; LED
remains on