5 and 6 Channel Capacitive Touch Sensor
Datasheet
5.20 Standby Sensitivity Register
Table 5.33 Standby Configuration Register
ADDR
R/W
REGISTER
B7
B6
B5
B4
B3
B2
B1
B0
DEFAULT
Standby
Sensitivity
42h
R/W
-
-
-
-
-
STBY_SENSE[2:0]
02h
The Standby Sensitivity register controls the sensitivity for sensors that are active in Standby.
Bits 2 - 0 - STBY_SENSE[2:0] - Controls the sensitivity for sensors that are active in Standby. The
sensitivity settings act to scale the relative delta count value higher or lower based on the system
parameters. A setting of 000b is the most sensitive while a setting of 111b is the least sensitive. At the
more sensitive settings, touches are detected for a smaller delta C corresponding to a “lighter” touch.
These settings are more sensitive to noise however and a noisy environment may flag more false
touches than higher sensitivity levels.
APPLICATION NOTE: A value of 128x is the most sensitive setting available. At the most sensitivity settings, the
MSB of the Delta Count register represents 64 out of ~25,000 which corresponds to a touch
of approximately 0.25% of the base capacitance (or a ΔC of 25fF from a 10pF base
capacitance). Conversely a value of 1x is the least sensitive setting available. At these
settings, the MSB of the Delta Count register corresponds to a delta count of 8192 counts
out of ~25,000 which corresponds to a touch of approximately 33% of the base capacitance
(or a ΔC of 3.33pF from a 10pF base capacitance).
Table 5.34 STBY_SENSE Bit Decode
STBY_SENSE[2:0]
2
1
0
SENSITIVITY MULTIPLIER
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
128x (most sensitive)
64x
32x (default)
16x
8x
4x
2x
1x - (least sensitive)
5.21 Standby Threshold Register
Table 5.35 Standby Threshold Register
ADDR
R/W
REGISTER
B7
B6
B5
B4
B3
B2
B1
B0
DEFAULT
Standby
Threshold
43h
R/W
-
64
32
16
8
4
2
1
40h
SMSC CAP1005 / CAP1006
Revision 1.1 (08-05-09)
DATA4S5HEET
SMSC [ SMSC CORPORATION ]
