Cypress CapSense CY3280-SmartSense, Руководство к набору

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22 CY3280-SmartSense CapSense Auto-Tuning Kit Guide, Doc. # 001-64672 Rev. *B
Load CapSense Example Projects
Figure 3-12. Output Window
3.2.3 Program Project
1. Open Program Part in PSoC Designer by selecting Program > Program Part
2. In the Program Part window
a. Select MiniProg1 in the PortSelection box
b. Set Acquire Mode to Power Cycle . If the board is already powered from AAA batteries or
from external supply through J2, set Acquire Mode to Reset
c. Set Verification to ON . This ensures that downloaded checksum matches actual checksum
d. Set Power Settings to 5V
e. Click program arrow to program the device
3. Wait until programming is completed to continue
4. Disconnect MiniProg1 from the kit
3.2.4 Run Project
Power the board using 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. See Figure 3-6 .
3.2.5 Self Tuning 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 value 10 pF 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 ; LED2 toggles again, as shown in Figure 3-6
6. Repeat step 2, 3, and 4 with 22 pF, 33 pF, and 68 pF axial capacitors
This demonstration shows that irrespective of variation in button parasitic capacitance, system works
the way it is indented to (LED toggles when the corresponding button is touched) due to the self
tuning capability of the SmartSense algorithm.
Note SmartSense user module works with sensor parasitic capacitance (Cp) as high as 45 pF.
Sensors with Cp greater than 45 pF are not guaranteed to work.