Datasheet

8 Channel Capacitive Touch Sensor with 8 LED Drivers
Datasheet
SMSC CAP1188 59 Revision 1.32 (01-05-12)
DATASHEET
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.
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 5.30 NEG_DELTA_CNT Bit Decode
NEG_DELTA_CNT[1:0]
NUMBER OF CONSECUTIVE NEGATIVE DELTA
COUNT VALUES1 0
0 0 8
0 1 16 (default)
1 0 32
1 1 None (disabled)
Table 5.31 CAL_CFG Bit Decode
CAL_CFG[2:0]
RECALIBRATION
SAMPLES (SEE
Note 5.1)
UPDATE TIME (SEE
Note 5.2)2 1 0
0 0 0 16 16
0 0 1 32 32
0 1 0 64 64 (default)
0 1 1 128 128