Datasheet

SAM9G45 [DATASHEET]
Atmel-6438O-ATARM-SAM9G45-Datasheet_08-Dec-15
934
It is possible to correct for the switch loss by performing the operation:
[VY
P
- VX
M
] / [VX
P
- VX
M
].
This requires additional measurements, as shown in Figure 39-3.
Figure 39-3. Touchscreen Switches Implementation
X
P
X
M
Y
M
VDDANA
Y
P
VDDANA
GND
GND
To the ADC
X
P
X
M
Y
P
VDDANA
GND
Switch
Resistor
Switch
Resistor
Y
P
Y
M
X
P
VDDANA
GND
Switch
Resistor
Switch
Resistor
Horizontal Position Detection
Vertical Position Detection