Cypress Semiconductor CY3280-MBR3 ユーザーズマニュアル
CY3280-MBR3 Evaluation Kit User Guide, Doc. #: 001-89905 Rev. *B
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Kit Operation
Note: The SW1 switch has three positions: at the NC-BTN2 position, the button is directly con-
nected to the CS4 pin on MBR3 and no additional capacitance is added. At the 10pF-BTN2 and
15pF-BTN2 positions, an additional trace capacitance of 10 pF and 15 pF respectively are added
to the CapSense button.The SW1 switch simulates changes in trace parasitic capacitance.
nected to the CS4 pin on MBR3 and no additional capacitance is added. At the 10pF-BTN2 and
15pF-BTN2 positions, an additional trace capacitance of 10 pF and 15 pF respectively are added
to the CapSense button.The SW1 switch simulates changes in trace parasitic capacitance.
Figure 3-20. SW1 Slide Switch in NC-BTN2 Position
2. Using a short/long trace by adjusting the SW3 slide switch on the kit
a. Power on the kit using USB or an external power supply on pin 4 of the J1 header.
b. Touch BTN4 on the kit. The LED corresponding to BTN4 will turn on, providing visual feed-
back on each touch.
) to add a longer
trace on BTN4.
d. The LED turns on as if a touch occurred due to the increase in capacitance. Now, press the
reset switch, SW2, to reset the board.
e. Touch BTN4 on the kit; the corresponding LED works normally and provides visual feedback
on each touch. This demonstrates the SmartSense Auto-Tuning algorithm, which automati-
cally tunes for the increase in CapSense button capacitance due to the long trace.
cally tunes for the increase in CapSense button capacitance due to the long trace.