8 Channel Capacitive Touch Sensor with 2 LED Drivers
Datasheet
Table 1.1 Pin Description for CAP1128 (continued)
PIN
NUMBER
UNUSED
CONNECTION
PIN NAME
PIN FUNCTION
PIN TYPE
Connect to
Ground
13
14
15
16
17
18
19
CS7
Capacitive Touch Sensor Input 7
AIO
Connect to
Ground
CS6
CS5
CS4
CS3
CS2
CS1
Capacitive Touch Sensor Input 6
Capacitive Touch Sensor Input 5
Capacitive Touch Sensor Input 4
Capacitive Touch Sensor Input 3
Capacitive Touch Sensor Input 2
Capacitive Touch Sensor Input 1
AIO
AIO
AIO
AIO
AIO
AIO
Connect to
Ground
Connect to
Ground
Connect to
Ground
Connect to
Ground
Connect to
Ground
20
VDD
GND
Positive Power supply
Ground
Power
Power
n/a
n/a
Bottom Pad
APPLICATION NOTE: When the ALERT# pin is configured as an active low output, it will be open drain. When it
is configured as an active high output, it will be push-pull.
APPLICATION NOTE: For the 5V tolerant pins that have a pull-up resistor, the pull-up voltage must not exceed 3.6V
when the CAP1128 is unpowered.
APPLICATION NOTE: The SPI_CS# pin should be grounded when SMBus, I2C, or BC-Link communications are
used.
The pin types are described in Table 1.2. All pins labeled with (5V) are 5V tolerant.
Table 1.2 Pin Types
PIN TYPE
DESCRIPTION
Power
DI
This pin is used to supply power or ground to the device.
Digital Input - This pin is used as a digital input. This pin is 5V tolerant.
Analog Input / Output -This pin is used as an I/O for analog signals.
AIO
Digital Input / Open Drain Output - This pin is used as a digital I/O. When it is used as an
output, it is open drain and requires a pull-up resistor. This pin is 5V tolerant.
DIOD
OD
Open Drain Digital Output - This pin is used as a digital output. It is open drain and requires
a pull-up resistor. This pin is 5V tolerant.
Push-pull Digital Output - This pin is used as a digital output and can sink and source
current.
DO
DIO
Push-pull Digital Input / Output - This pin is used as an I/O for digital signals.
Revision 1.32 (01-05-12)
SMSC CAP1128
DATA1S2HEET
SMSC [ SMSC CORPORATION ]
