Multiple Channel Capacitive Touch Sensor and LED Driver
Datasheet
The Sampling Configuration register controls the length of the sampling window of selected Captive
Touch Sensor channels as indicated in the Sampling Channel Select register.
Increasing the sampling window time will have two effects. The first effect will be to increase the
effective sensitivity of that particular channel so that a touch may be detected with a smaller ΔC or to
allow for degrees of proximity detection. However, at the larger sampling times, the resolution of the
measurement is reduced.
The second effect will be increase the overall round robin rate (and all timing associated with the round
robin rate such as re-calibration times, repeat rate times, and maximum duration times).
All Capacitive Touch Sensors default to a sampling time of 2.5ms. Increasing the sampling time of any
single channel will increase the overall polling cycle by the same amount.
Bits 2 - 0 - OVERSAMP_RATE[2:0] - Determine the sample window of all selected sensors.
5.33 Sensor Base Count Registers
Table 5.50 Sensor Base Count Registers
ADDR
R/W
REGISTER
B7
B6
B5
B4
B3
B2
B1
B0
DEFAULT
Sensor 1 Base
Count
50h
R
128
64
32
16
8
4
2
1
00h
Sensor 2 Base
Count
51h
52h
53h
54h
55h
56h
57h
58h
59h
5Ah
5Bh
5Ch
5Dh
R
R
R
R
R
R
R
R
R
R
R
R
R
128
128
128
128
128
128
128
128
128
128
128
128
128
64
64
64
64
64
64
64
64
64
64
64
64
64
32
32
32
32
32
32
32
32
32
32
32
32
32
16
16
16
16
16
16
16
16
16
16
16
16
16
8
8
8
8
8
8
8
8
8
8
8
8
8
4
4
4
4
4
4
4
4
4
4
4
4
4
2
2
2
2
2
2
2
2
2
2
2
2
2
1
1
1
1
1
1
1
1
1
1
1
1
1
00h
00h
00h
00h
00h
00h
00h
00h
00h
00h
00h
00h
00h
Sensor 3 Base
Count
Sensor 4 Base
Count
Sensor 5 Base
Count
Sensor 6 Base
Count
Sensor 7 Base
Count
Sensor 8 Base
Count
Sensor 9 Base
Count
Sensor 10
Base Count
Sensor 11
Base Count
Sensor 12
Base Count
Sensor 13
Base Count
Sensor 14
Base Count
SMSC CAP1014
Revision 1.65 (08-11-09)
DATA6S1HEET
SMSC [ SMSC CORPORATION ]
