SX8644I05AWLTRT Semtech, SX8644I05AWLTRT Datasheet - Page 16

• Manufacturer Part Number: SX8644I05AWLTRT
• Description: 12-ch Capacitive Touch Solution (Button & Slider)
• Manufacturer: Semtech

SX8644
Ultra Low Power, Capacitive Button and Slider
Touch Controller (12 sensors) with Enhanced LED Drivers
WIRELESS & SENSING
DATASHEET
The position belonging to the minimum and associated to a sensor is defined arbitrarily. The SX8644 defines the
minimum position to the sensor with the lowest CAP pin index. E.g. if CAP0 is a button (or disabled) and CAP1 to
CAP7 are the sensors of the slider then the position ‘zero’ starts at CAP1 and the maximum is found at CAP7.
In addition to the slider position, the SX8644 allows to detect finger movements. The movement occurs if the
finger position changes a certain step size between two succeeding scan periods. A very slow moving finger will
not be considered as a movement as the changing position will be minor. The SX8644 allows detecting a move
low (direction max to min) (see Figure 14) and a move high (direction min to max) (see Figure 15).
Slider Move Low
Figure 14
Slider Move High
Figure 15
Revision 7_6, October 12
© 2012 Semtech Corp.
www.semtech.com
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