SX8644EVK Semtech, SX8644EVK Datasheet - Page 45

• Manufacturer Part Number: SX8644EVK
• Manufacturer: Semtech

Specifications of SX8644EVK

• Lead Free Status / RoHS Status: Not Compliant

ADVANCED COMMUNICATIONS & SENSING
CapSensitivity0_1, CapSensitivity2_3, CapSensitivity4_5,
CapSensitivity6_7, CapSensitivity8_9, CapSensitivity10_11:
Revision 7_3, January 10
The minimum position of the slider is associated to the CAP pin, attributed to the slider, with the lowest index
(in Figure 48 this is CAP2).
The maximum position of the slider is associated to the CAP pin, attributed to the slider, with the highest index
(in Figure 48 this is CAP6).
The sensitivity of the sensors can be set between 8 values. The higher the sensitivity is set the larger the value
of the ticks will be.
The minimum sensitivity can be used for thin overlay materials and large sensors, while the maximum
sensitivity is required for thicker overlay and smaller sensors.
The required sensitivity needs to be determined during a product development phase. Too low sensitivity
settings result in missing touches. Too high sensitivity settings will result in fault detection of fingers hovering
above the sensors.
The sensitivity is identical for all sensors in common sensitivity mode using the bits CapSensitivity0_1[7:4] and
can be set individually using register CapModeMisc[2].
The maximum number of ticks that can be obtained depends on the selected sensitivity as illustrated in Table
17.
Figure 48
Button and Slider good/bad configuration examples (II)
Table 17
Sensitivity
Touch Controller (12 sensors) with Enhanced LED Drivers
© 2009 Semtech Corp.
1
2
3
4
5
6
7
0
ASI Maximum Tick Levels
45
Ultra Low Power, Capacitive Button and Slider
Maximum Tick Level
Approximate
1000
2000
3000
4000
5000
6000
7000
8000
DATASHEET
www.semtech.com
SX8644