Cypress Semiconductor CapSense CY8CKIT-024, Руководство пользователя, Страница: 14 / 29

Kit Hardware
CY8CKIT-024 CapSense
®
Proximity Shield Kit Guide, Doc. No. 001-92568 Rev. *B 14
2.2.2 CY8CKIT-024 System
The CY8CKIT-024 kit contains five capacitive proximity sensors laid out in a shape and pattern that allow a large proximity-
sensing distance and gesture detection. These sensors can be interfaced with PSoC 4 devices present on Cypress PSoC
Pioneer Kits through Arduino-compatible headers, as
Figure 2-6 shows.
Figure 2-6: CY8CKIT-024 System Block Diagram
A
rd
u
in
o
C
o
n
n
e
c
to
rs
KitProg
PSoC 4xxx
SWD
CapSense
MCU
A
rd
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in
o
C
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c
to
rs
LEDs
Proximity Sensors
Cypress PSoC Pioneer Kit
(CY8CKIT-040/CY8CKIT-042)
CY8CKIT-024
USB
PSoC Creator/Programmer
In the CY8CKIT-024 system, the CapSense circuitry in the PSoC device on the baseboard (such as CY8CKIT-040 or
CY8CKIT-042 ) senses the changes in the capacitance of the proximity sensors on the CY8CKIT-024 kit. Based on the
information about capacitance changes on different sensors received from the CapSense block, the PSoC MCU determines
the presence of a target object, like a hand, and correspondingly drives the LEDs on
CY8CKIT-024 .
You can program the PSoC device on the baseboard through the onboard KitProg hardware, which communicates to the
software programming tool (
PSoC Programmer ) through the USB interface on the board. You can develop firmware
applications for PSoC 4 devices by using PSoC Creator .
AN92239
– Proximity Sensing with CapSense
provides example projects that you can use with the CY8CKIT-024 system to
implement large proximity-sensing distance, liquid-tolerant proximity sensing, and gesture detection applications.
2.3 Functional Description
2.3.1 Sensor Pattern
The CY8CKIT-024 kit contains five proximity sensors: PROX, PS1, PS2, PS3, and PS4. PROX is designed in the form of a
loop for a large proximity-sensing distance. PS1, PS2, PS3, and PS4 are designed as strips for vertical and horizontal
gesture detection. To enable ground coupling for the proximity sensors, a GND/SHIELD loop is provided between the
PROX loop and the PSx (proximity sensors PS1 through PS4) strips, as shown in
Figure 2-7. Ground coupling improves the
ESD immunity of the proximity sensors. Optionally, you can drive the GND/SHIELD loop with the driven shield instead of
connecting it to ground to achieve liquid tolerance. For details on driven shield, grounding recommendations, and layout
guidelines, refer to the
Getting Started with CapSense Design Guide .