CY8C20111-SX1I CapSense Analog System

CY8C20111-SX1I CapSense Analog System
The Analog System contains the capacitive sensing hardware.
Several hardware algorithms are supported. This hardware
performs capacitive sensing and scanning without requiring
external components. Capacitive sensing is configurable on
each GPIO pin. Scanning of enabled CapSense pins is
completed quickly and easily across multiple ports.
Figure 1.  Analog System Block Diagram
Analog Multiplexer System
The Analog Mux Bus connects to every GPIO pin. Pins are
connected to the bus individually or in any combination. The bus
also connects to the analog system for analysis with the
CapSense block comparator.
Switch control logic enables selected pins to precharge
continuously under hardware control. This enables capacitive
measurement for applications such as touch sensing. Other
multiplexer applications include:
 Complex capacitive sensing interfaces such as sliders and
touch pads
 Chip-wide mux that enables analog input from any I/O pin
 Crosspoint connection between any I/O pin combinations