8 Channel Capacitive Touch Sensor with 2 LED Drivers
Datasheet
The Recalibration Configuration register controls the automatic re-calibration routine settings as well
as advanced controls to program the Sensor Input Threshold register settings.
Bit 7 - BUT_LD_TH - Enables setting all Sensor Input Threshold registers by writing to the Sensor
Input 1 Threshold register.
‘0’ - Each Sensor Input X Threshold register is updated individually.
‘1’ (default) - Writing the Sensor Input 1 Threshold register will automatically overwrite the Sensor
Input Threshold registers for all sensor inputs (Sensor Input Threshold 1 through Sensor Input
Threshold 8). The individual Sensor Input X Threshold registers (Sensor Input 2 Threshold through
Sensor Input 8 Threshold) can be individually updated at any time.
Bit 6 - NO_CLR_INTD - Controls whether the accumulation of intermediate data is cleared if the noise
status bit is set.
‘0’ (default) - The accumulation of intermediate data is cleared if the noise status bit is set.
‘1’ - The accumulation of intermediate data is not cleared if the noise status bit is set.
APPLICATION NOTE: Bits 5 and 6 should both be set to the same value. Either both should be set to ‘0’ or both
should be set to ‘1’.
Bit 5 - NO_CLR_NEG - Controls whether the consecutive negative delta counts counter is cleared if
the noise status bit is set.
‘0’ (default) - The consecutive negative delta counts counter is cleared if the noise status bit is set.
‘1’ - The consecutive negative delta counts counter is not cleared if the noise status bit is set.
Bits 4 - 3 - NEG_DELTA_CNT[1:0] - Determines the number of negative delta counts necessary to
trigger a digital re-calibration as shown in Table 5.30.
Table 5.30 NEG_DELTA_CNT Bit Decode
NEG_DELTA_CNT[1:0]
NUMBER OF CONSECUTIVE NEGATIVE DELTA
1
0
COUNT VALUES
0
0
1
1
0
1
0
1
8
16 (default)
32
None (disabled)
Bits 2 - 0 - CAL_CFG[2:0] - Determines the update time and number of samples of the automatic re-
calibration routine. The settings apply to all sensor inputs universally (though individual sensor inputs
can be configured to support re-calibration - see Section 5.11).
Table 5.31 CAL_CFG Bit Decode
CAL_CFG[2:0]
RECALIBRATION
SAMPLES (SEE
UPDATE TIME (SEE
2
1
0
Note 5.1)
Note 5.2)
0
0
0
0
0
1
0
1
0
16
32
64
16
32
64 (default)
Revision 1.32 (01-05-12)
SMSC CAP1128
DATA5S8HEET
SMSC [ SMSC CORPORATION ]
