Cirrus Logic EP93xx - Manual (Page 749)

DS785UM1 25-11
Copyright 2007 Cirrus Logic
Analog Touch Screen Interface
EP93xx User’s Guide
2
5
2
5
25
Figure 25-5. 5-Wire Analog Resistive Interface Switching Diagram
5 WIRE ANALOG RESISTIVE INTERFACE SWITCHING DIAGRAM
V+
V-
Z+/-
Z-/+
Not used
Not used
Wiper
Not used
SW12
SW14
SW13
SW20
A/D CONVERTER
IN
REF+
REF-
VDD
SW21
SW19
SW11
SW0
SW1
SW2
SW3
SW24
SW25
SW26
SW27
100K SW23
SW22 100K
SW9
SW10
SW6
SW7
SW4
SW5
SW15
SW16
SW17
SW18
SW12
SW14
SW13
SW20
A/D CONVERTER
IN
REF+
REF-
VDD
SW21
SW19
SW11
SW0
SW1
SW2
SW3
SW24
SW25
SW26
SW27
100K SW23
SW22 100K
SW9
SW10
SW6
SW7
SW4
SW5
SW15
SW16
SW17
SW18
SW12
SW14
SW13
SW20
A/D CONVERTER
IN
REF+
REF-
VDD
SW21
SW19
SW11
SW0
SW1
SW2
SW3
SW24
SW25
SW26
SW27
100K SW23
SW22 100K
SW9
SW10
SW6
SW7
SW4
SW5
SW15
SW16
SW17
SW18
V+
V-
Z+/-
Z-/+
Not used
Not used
Wiper
Not used
V+
V-
Z+/-
Z-/+
Not used
Not used
Wiper
Not used
Not used
Not used
Wiper
Not used
SW12
SW14
SW13
SW20
A/D CONVERTER
IN
REF+
REF-
VDD
SW21
SW19
SW11
SW0
SW1
SW2
SW3
SW24
SW25
SW26
SW27
100K SW23
SW22 100K
SW9
SW10
SW6
SW7
SW4
SW5
SW15
SW16
SW17
SW18
V+
V-
Z+/-
Z-/+
DISCHARGE ALL LINES SAMPLE X-AXIS SAMPLE Y-AXIS TOUCH DETECT
SW8
VBAT
TOUCH_PRESS
SW28
SW30
DAC SW29