User manual

CY3280-MBR3 Evaluation Kit User Guide, Doc. #: 001-89905 Rev. *B 34
Hardware
4.3 Functional Description
4.3.1 CY8CMBR3116 CapSense Controller
The CY8CMBR3116 CapSense controller includes the following features:
■ SmartSense Auto-Tuning – Cypress' CapSense algorithm that continuously compensates for
system, manufacturing, and environmental changes.
■ Proximity sensing – Supports configurability of sensors for proximity sensing.
■ Button sensor auto-reset – Prevents a stuck sensor when a metal object is placed close to that
sensor.
■ Flanking sensor suppression (FSS) – Eliminates false touches by distinguishing between signals
from closely spaced buttons.
■ Toggle (touch on/off) – Mimics the mechanical button functionality by toggling sensor output sta-
tus on every sensor activation.
■ LED-on time – Provides better visual feedback by enabling the general-purpose output (GPO) to
be on for a configurable period after the button is released.
■ Debounce control – Prevents false trigger by specifying the minimum time for which a sensor
must be touched for a valid ON status.
■ Buzzer signal output – Enables direct drive of a buzzer with configurable frequency.
■ Host-controlled GPO – Enables device GPOs to be controlled by the host (I
2
C master).
■ LED brightness control – Offers duty cycle configurability to control the brightness of the LEDs
connected to the GPOs.
■ Wake-on approach – Wakes the device from low-power and switches to the active state using
proximity sensors.
■ Water tolerance – Enables water-tolerant user interface applications. The shield electrode should
be enabled through the register map to prevent false touches under wet conditions. To prevent
false touches in streaming water conditions, both the shield electrode and guard sensor need to
be enabled. However, the MBR3 kit does not have the guard sensor loop. So, water tolerance
under streaming water conditions cannot be tested on the board.
■ I
2
C slave – An I
2
C interface with support for 50/100/400-kHz clock speeds and hardware slave
address comparison.
■ Host interrupt – Alerts the host processor upon touch detection; for every touch and release
event, an active low pulse of typically 250 µs is generated.
■ System diagnostics – Supports production testing and debugging.
See the CY8CMBR3116 datasheet for more details on these features.
The CY3280-MBR3 EVK can be configured using the EZ-Click 2.0 customizer tool. The kit includes
three configuration files with specific features described in Configuration Files on page 51. Additional
configurations can be generated and applied to the kit using this tool.
See the EZ-Click 2.0 Customizer Tool User Guide for additional details on how to generate more
configurations to evaluate the features in this section using the EZ-Click 2.0 customizer tool. This
guide is available at the location <Install Directory>\EZ-Click\<version>\Documenta-
tion.
4.3.1.1 Pin Mapping Between CY8CMBR3116 and CY3280-MBR3 EVK
The CY8CMBR3116 device can be configured for 16 button sensors of which two sensors are con-
figurable as proximity sensors. The kit demonstrates four button sensors and one proximity sensor.