sx8654evk Semtech Corporation, sx8654evk Datasheet - Page 33

• Manufacturer Part Number: sx8654evk
• Description: Haptics Enabled 4/5-wire Resistive Touchscreen Controller With Proximity Sensing
• Manufacturer: Semtech Corporation

ADVANCED COMMUNICATIONS & SENSING
touchscreen is used as the proximity sensor and is being touched when the conversion is performed, the
proximity measurement result may be incorrect.
If the screen is not touched, only the proximity sensing operation is performed.
In PENDET and PENTRG mode, a proximity sensing operation will be performed regularly as defined in
PROXSCANPERIOD, but only if pen is not detected.
Rev 1 – 25
PENSTAT
CONVSTAT
NIRQ
I2C Read RegIrqSrc
TOUCHRATE
Figure 43 – Pen Detect Mode (RegIrqMsk[6:2] = 00011 ; PROXSCANPERIOD = 001 ie 1/TOUCHRATE)
Figure 41 – Manual Mode – CONVERT Command (CHAN = Y ; PROXSCANPERIOD != 0; Pen down)
Idle
Pen Detection
tick
NIRQ (RegIrqMsk[6:3]=0001)
NIRQ (RegIrqMsk[6:3]=0001)
Channel Bias
Channel Conv e rsion
Channel Bias
Channel Conv e rsion
CONVSTAT
CONVSTAT
Figure 42 – Manual Mode – CONVERT Command (CHAN = Y ; PROXSCANPERIOD != 0, Pen up)
I2C
I2C
th
July 2011
Touch Conversion
Proximity Sensing
Pen Touch
CONVERT Y
CONVERT Y
PROX
PROX
Resistive Touchscreen Controller with Proximity Sensing
33
POWDLY
Pen Release
Y
Y
READ CHANNEL
READ CHANNEL
SX8657/SX8658
Haptics Enabled 4/5-Wire
www.semtech.com