CAP1188-1-CP-TR Datasheet, PDF (1/93 Pages) Microchip Technology – 8 Channel Capacitive Touch Sensor with 8 LED Drivers

CAP1188
8 Channel Capacitive Touch Sensor
with 8 LED Drivers
PRODUCT FEATURES
Datasheet
General Description
The CAP1188, which incorporates SMSC’s RightTouch^{® 1}
technology, is a multiple channel Capacitive Touch sensor
with multiple power LED drivers. It contains eight (8)
individual capacitive touch sensor inputs with
programmable sensitivity for use in touch sensor
applications. Each sensor input automatically recalibrates
to compensate for gradual environmental changes.
The CAP1188 also contains eight (8) LED drivers that offer
full-on / off, variable rate blinking, dimness controls, and
breathing. Each of the LED drivers may be linked to one of
the sensor inputs to be actuated when a touch is detected.
As well, each LED driver may be individually controlled via
a host controller.
The CAP1188 includes Multiple Pattern Touch recognition
that allows the user to select a specific set of buttons to be
touched simultaneously. If this pattern is detected, then a
status bit is set and an interrupt generated.
Additionally, the CAP1188 includes circuitry and support for
enhanced sensor proximity detection.
The CAP1188 offers multiple power states operating at low
quiescent currents. In the Standby state of operation, one
or more capacitive touch sensor inputs are active and all
LEDs may be used. If a touch is detected, it will wake the
system using the WAKE/SPI_MOSI pin.
Deep Sleep is the lowest power state available, drawing
5uA (typical) of current. In this state, no sensor inputs are
active. Driving the WAKE/SPI_MOSI pin or communications
will wake the device.
1. SMSC, the SMSC logo and RightTouch are registered trademarks
and the RightTouch logo is a trademark of Standard Microsystems
Corporation (“SMSC”).
Applications
„ Desktop and Notebook PCs
„ LCD Monitors
„ Consumer Electronics
„ Appliances
Features
„ Eight (8) Capacitive Touch Sensor Inputs
— Programmable sensitivity
— Automatic recalibration
— Individual thresholds for each button
„ Proximity Detection
„ Multiple Button Pattern Detection
„ Calibrates for Parasitic Capacitance
„ Analog Filtering for System Noise Sources
„ Press and Hold feature for Volume-like Applications
„ Multiple Communication Interfaces
— SMBus / I²C compliant interface
— SMSC BC-Link interface
— SPI communications
— Pin selectable communications protocol and multiple
slave addresses (SMBus / I²C only)
„ Low Power Operation
— 5uA quiescent current in Deep Sleep
— 50uA quiescent current in Standby (1 sensor input
monitored)
— Samples one or more channels in Standby
„ Eight (8) LED Driver Outputs
— Open Drain or Push-Pull
— Programmable blink, breathe, and dimness controls
— Can be linked to Capacitive Touch Sensor inputs
„ Dedicated Wake output flags touches in low power state
„ System RESET pin
„ Available in 24-pin 4mm x 4mm RoHS compliant QFN
package
Block Diagram
LED1 LED2 LED3 LED4
RESET
VDD GND
WAKE / SPI_MOSI
SPI_CS#
LED Driver, Breathe, and
Dimness control
Capacitive Touch Sensing Algorithm
SMBus /
BC-Link or
SPI Slave
Protocol
SMCLK / BC_CLK /
SPI_CLK
SMDATA / BC_DATA / SPI_MSIO /
SPI_MISO
ALERT# / BC_IRQ#
ADDR_COMM
LED5 LED6 LED7 LED8
CS1 CS2 CS3 CS4 CS5 CS6 CS7 CS8
SMSC CAP1188
DATASHEET
Revision 1.32 (01-05-12)