MAX1233_05 Datasheet, PDF (17/45 Pages) Maxim Integrated Products – ±15kV ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller

±15kV ESD-Protected Touch-Screen
Controllers Include DAC and Keypad Controller
SIMPLIFIED KEYPAD CIRCUITRY
DRIVERS PULL HIGH
OR GO THREE-STATE
C1
C2
C3
C4
R1
TO KEYPAD
WAKEUP AND
DEBOUNCE
R2
LOGIC
R3
KEYPAD
R4
Figure 7. Key-Press Detection Circuitry
X+
X+
PENIRQ
BUSY
CS
DATA
READ
DOUT
TOUCH-
SCREEN
DATA
Figure 8a. Timing Diagram for Touch-Initiated Screen Scan
PENIRQ
BUSY
CS
DIN
DOUT
DATA
READ
TOUCH-
SCREEN
DATA
Figure 8b. Timing Diagram for Host-Initiated Screen Scan
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