General Description
The MK715 Touch Screen Controller IC provides all the screen drive, Analog to Digital converter (ADC) and control circuits to easily interface to 4-wire analog resistive touch screens. It also includes a general purpose A to D converter and a clock synthesizer.

Features
• Tiny 20 pin SSOP (150 mil body)
• 4 microamp standby current
• Less than 3mA active current at 3.3V, including screen drive
• Touch pressure can be measured
• One or two general purpose A to D inputs
• On-chip voltage reference
• 32.768kHz crystal/clock input
• MHz clock outputs available
• Operates with four wire touch screens
• Ratiometric conversion eliminates screen calibration
• Automatic wake up upon screen touch
• Programmable conversion rate to a maximum of 303 points per second
• 3.3V or 5V supply (2.7V version available)
• 10 bit A/D converter
• Full powerdown control
• Touch screen is directly driven - no external transistors are required
• A to D Converter guaranteed monotonic
• 3 or 4 wire serial interface

Applications
• Notebook Computers
• Handheld Computers
• PDAs
• Touch-screen kiosks