Multiple Channel Capacitive Touch Sensor and LED Driver
Datasheet
4.1
Power States
The CAP1014 has four operating states depending on the status of the SLEEP, DEACT, and DSLEEP
bits (see Section 5.1). They are described below and summarized in Table 4.1. When the device
transitions between power states, previously detected touches (for deactivated channels) are cleared
and the status bits reset.
1. Fully Active - The device is fully active. It is monitoring all active Capacitive Sensor channels and
driving all LED channels as defined.
2. Sleep - The device is in Sleep Mode. It is monitoring a limited number of Capacitive Sensor
channels (default 0). Interrupts will still be generated based on the active channels. The device will
still respond to SMBus commands normally and can be returned to the Fully Active mode by
clearing the SLEEP bit. The LED11 channel is controlled via the PWR_LED control (see
Section 5.1). All other LEDs will not be affected.
3. Deep Sleep - The device is in Deep Sleep mode. It is not monitoring any Capacitive Sensor
channels or the SMBus. The LED11 channel is controlled via the PWR_LED control (see
Section 5.1). All other LEDs will have PWM controls suspended so they should be disabled prior
to entering this mode. If these LEDs are not disabled, then the system will show excess current
draw from these LEDs.
When the device leaves the Deep Sleep mode (by externally driving the ALERT pin to its active
state), then it automatically returns to its defined state and clears the DSLEEP bit. When the device
enters the Deep Sleep mode, it will release control to the ALERT pin and will change the direction
of the ALERT pin (i.e. the device will monitor the ALERT pin instead of driving it).
4. Inactive - The device is inactive. It is not monitoring any Capacitive Sensor channels. The device
will still respond to SMBus commands normally and can be returned to Fully Active Mode by
clearing the DEACT bit. All LEDs will have PWM controls suspended so they should be disabled
prior to entering this mode. If these LEDs are not disabled, then the system will show excess
current draw from these LEDs.
Table 4.1 Power Modes
POWER MODE
DEACT
SLEEP
DSLEEP
Fully Active
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
Deep Sleep waking to Fully Active
Sleep
Deep Sleep waking to Sleep
Inactive
Deep Sleep waking to Inactive
Inactive
Deep Sleep waking to Inactive
The priority of power control signals is:
1. DSLEEP - when set will override DEACT, disable all LEDs except LED11 then disable SMBus
communications.
2. DEACT - when set, will override the SLEEP controls. It will disable sensor measurement and all
LEDs.
3. SLEEP - when set, will enable Sleep mode.
SMSC CAP1014
Revision 1.65 (08-11-09)
DATA2S1HEET
SMSC [ SMSC CORPORATION ]
