8 Channel Capacitive Touch Sensor with 2 LED Drivers
Datasheet
Table 5.1 Register Set in Hexadecimal Order (continued)
REGISTER
ADDRESS
DEFAULT
VALUE
R/W
REGISTER NAME
FUNCTION
PAGE
R
Sensor Input
Calibration LSB 2
Stores the 2 LSBs of the calibration
value for sensor inputs 5 - 8
BAh
FDh
FEh
FFh
00h
52h
5Dh
83h
Page 80
Stores a fixed value that identifies
each product
R
R
R
Product ID
Manufacturer ID
Revision
Page 81
Page 81
Page 81
Stores a fixed value that identifies
SMSC
Stores a fixed value that represents
the revision number
During Power-On-Reset (POR), the default values are stored in the registers. A POR is initiated when
power is first applied to the part and the voltage on the VDD supply surpasses the POR level as
specified in the electrical characteristics. Any reads to undefined registers will return 00h. Writes to
undefined registers will not have an effect.
When a bit is “set”, this means that the user writes a logic ‘1’ to it. When a bit is “cleared”, this means
that the user writes a logic ‘0’ to it.
5.1
Main Control Register
Table 5.2 Main Control Register
ADDR
00h
R/W
REGISTER
B7
B6
B5
B4
B3
B2
B1
B0
DEFAULT
R/W
Main Control
GAIN[1:0]
STBY
DSLEEP
-
-
-
INT
00h
The Main Control register controls the primary power state of the device.
Bits 7 - 6 - GAIN[1:0] - Controls the gain used by the capacitive touch sensing circuitry. As the gain is
increased, the effective sensitivity is likewise increased as a smaller delta capacitance is required to
generate the same delta count values. The sensitivity settings may need to be adjusted along with the
gain settings such that data overflow does not occur.
APPLICATION NOTE: The gain settings apply to both Standby and Active states.
Table 5.3 GAIN Bit Decode
GAIN[1:0]
1
0
CAPACITIVE TOUCH SENSOR GAIN
0
0
1
1
0
1
0
1
1
2
4
8
Bit 5 - STBY - Enables Standby.
SMSC CAP1128
Revision 1.32 (01-05-12)
DATA4S1HEET
SMSC [ SMSC CORPORATION ]
