Samsung S3C2440A - Manual (Page 414)

ADC AND TOUCH SCREEN INTERFACE S3C2440A RISC MICROPROCESSOR
16-2
ADC & TOUCH SCREEN INTERFACE OPERATION
BLOCK DIAGRAM
Figure 16-1 shows the functional block diagram of A/D converter and Touch Screen Interface. Note that the A/D
converter device is a recycling type.
Pullup
Waiting for Interrupt Mode
INT_TC
INT_ADC
8:1
MUX
A/D
Converter
ADC input
control
Touch Screen
Pads control
Interrupt
Generation
ADC interface
&Touch Screen
Control
AVDD
AGND
XP
XM
YP
YM
A[3:0]
note
note
Figure 16-1. ADC and Touch Screen Interface Functional Block Diagram
*note (symbol )
When Touch Screen device is used; XM or PM is only connected ground for Touch Screen I/F.
When Touch Screen device is not used, XM or PM is connecting Analog Input Signal for Normal ADC conversion.