Touch Panel Controller Connection Circuit - Epson S5U1C17801T1100 Hardware Manual

Touch Panel Controller Connection Circuit

The touch panel function is installed in the LCD panel module on the SVT17801. The following shows how the
touch panel is connected to the S1C17801.
UNR31A300L
LCD panel module
(EW32F92FLWP)
LEFT
TOP
RIGHT
BOTTOM
C109 C108
470P 470P
In the above connection diagram (figure 11.1.1), panel s touch position information entered from AIN5/AIN6 is ob-
tained as an AD value while the circuit shown above is controlled by P33/P34 of the S1C17801. The following lists
each signal status of the panel module and the S1C17801.
S1C17801
LCD panel module
In order to obtain panel s touch position information on X-axis of the figure 11.1.2, an AD value obtained from
AIN6 is used to determine the position of X-axis when P33 is turned LOW while P34 HIGH as shown in X-axis
fields shown in the table 11.1.1. (The AIN6 value becomes gradually larger for the left side of the figure 11.1.2.)
On the other hand, to obtain panel s touch position information on the Y-axis of the figure 11.1.2, an AD value ob-
tained from AIN5 is used to determine the position of Y-axis when P33 is turned HIGH while P34 LOW as shown
in Y-axis fields of table 11.1.1. (The AIN6 value becomes gradually larger for the upper side of the figure 11.1.2.)
This principle to obtain X-axis and Y-axis data helps acquire two-dimensional touch position information by obtain-
ing X-axis and Y-axis AD values while alternately switching between P33 and P34 statuses with a short duration.
EPSON
AIN6 (Voltage HIGH)
Fig. 11.1.2 Image of X-axis and Y-axis Analog Values of Touch Panel
S5U1C17801T1100 HARDWARE MANUAL
(SOFTWARE EVALUATION TOOL FOR S1C17801)
V
DD
Q101
Q103
UNR31A300L
Q102
UNR5213
Q104
UNR5213
Fig. 11.1.1 Touch Panel Connection Circuit
Table 11.1.1 Function of Touch Panel Control Signal
Pin No.
P33
P34
AIN5
AIN6
LEFT
TOP
RIGHT
BOTTOM
SVT17801 LCD BOARD
X-axis
AIN6 (Voltage LOW)
11 LCD PANEL CONNECTION CIRCUIT
V
DD
U102
6
1Y
5
V
CC
4
2Y
C110
74LVC2G14
0.1µF
X-axis
LOW
HIGH
LOW
0 to V (V)
DD
HIGH
Hi-Z
LOW
0 to V (V)
DD
Y-axis
EPSON
S1C17801
P33
P34
AIN5
AIN6
1
1A
2
GND
3
2A
Y-axis
HIGH
LOW
0 to V (V)
DD
LOW
Hi-Z
HIGH
0 to V (V)
DD
LOW
AIN5 (Voltage HIGH)
AIN5 (Voltage LOW)
33