CRTOUCH Datasheet, PDF (5/68 Pages) Freescale Semiconductor, Inc – Capacitive and Resistive Touch Sensing Application Specific IC.

1.3 Recommended system connections
Pins and Connections
Figure 3. Recommended system connections
NOTE
1. Resistive touch screen signals are bi-directional only for four-wire screens. For five-wire 5WS is input and the other
four signals are outputs.
2. COMMSEL is connected to ground only if UART communication is desired. Otherwise it can be left unconnected.
3. I2C and UART communications are mutually exclusive. Only one can work during the device run time. The other pins
from the other communication protocol can be un-connected.
4. All unused pins can be left as Not Connected. Connecting them to ground may increase power consumption.
CRTouch Data Sheet, Rev. 3
Freescale Semiconductor
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