Specifications

94 Control and Automation Solutions Guide
Featured Products
Benefits
• Enable sophisticated touch-screen
panels with minimal processor
overhead
◦ Digital preprocessing of touch
events
◦ Autonomous mode and FIFO allows
multiple touch capture between µC
interrupts
◦ Touch categorization further frees
system microprocessor processing
• Designed for reliable operation in
harsh environments
◦ -40°C to +105°C operating
temperature range
◦ 4-wire reliable touch screens
supported
◦ 25MHz SPI interface
◦ ±8kV ESD protected inputs (X+, X-,
Y+, Y-)
Simple to Implement Resistive Touch-Screen
Controllers Reduce µP Overhead
MAX11800–MAX11803
The MAX11800–MAX11803 low-power touch-screen controllers operate from a 1.70V
to 3.6V single supply, targeting power-sensitive applications. The devices contain a
12-bit SAR ADC and a multiplexer to interface with a resistive touch-screen panel.
Digital preprocessing and the smart interrupt function generator greatly reduce the
frequency of interrupt servicing required from the microprocessor. Autonomous
mode further reduces overhead by allowing repeated scans. The on-chip FIFO stores
the results until read by the microprocessor. Results are further categorized as “initial
touch,” “continuing touch,” or “touch release.”
Typical application circuit for the MAX11800, MAX11802 resistive touch-screen controllers. Very few external parts are needed.
TOUCH SCREEN
X+
Y+
X-
Y-
GPIO
0.1µF
DOUT
CLK
DIN
CS
V
DD
V
DD
TIRQ
DIN
CLK
DOUT
CS
GND
AUX
AUX INPUT
HOST
PROCESSOR
MAX11800
MAX11802