Microchip Technology Inc
Menu

2D Analog Resistive Touch

The AR11xx series is a legacy product suite not recommended for new designs for analog resistive touch.
Introduction to Resistive Touch

Analog resistive technology is popular because of its:

  • Low-cost sensors
  • Acceptance of finger, glove or stylus-pen inputs
  • Overall ease of manufacturing and integration into applications

Suitable applications for analog resistive include:

  • Mobile phones, industrial automation, retail point-of-sale, gaming/entertainment and automobile navigation systems
Resistive - How Does it Work?
An analog resistive touch screen is comprised of two layers, the flex and the stable layer. These layers are coated with a thin electrically conductive coating of Indium Tin Oxide (ITO). These two layers are separated by the spacer layer. When touched, the flex layer comes in contact with the stable layer. The point of contact creates a voltage divider in the X and Y directions. This voltage is then used to find the relative position of the touch activation.
Selecting a Touch Sensor

Three basic analog resistive sensor constructions:

  • Most cost effective - 4-wire
  • Most durable - 5-wire
  • Most flexible - 8-wire
AR1000 Series Touch Controllers
  • Turnkey touch solution
  • Built-in decoding and advanced filtering
  • Controller-driven calibration
  • Low cost with few external components
  • Universal 4-, 5-, and 8-wire support
  • Fast time to market
  • Small footprint
  • Low power
  • SPI, I2C, UART support
  • Developed by touch experts

Resistive Touch Screen Controller Comparison

Microchip Benefit Other Touch Screen Controllers
Touch Solution Turnkey touch solution - easy integration for an accelerated development cycle Incomplete, require significant engineering to decode, filter and calibrate
Touch Coordinates Delivers accurate touch coordinates with built-in decoding and advanced filtering Not provided, require customer to become a "touch" expert
Software Driver Support Controller-driven callibration - no software drivers needed! Incomplete, require that users write calibration drivers
Design Cost Low - including few required components High - including required components
Sensor Support Universal sensor support for all 4-, 5- and 8-wire screens (wide tolerance range) Typically support 4-wire only (tolerance variation may require redesign)
Design Time to Market Fast - no learning curve, works out of the box Slow - long learning curve, trial and error development
PCB Real Estate Small footprint, minimal real estate Large footprint
Touch Expertise 15+ years of touch expertise Minimal
Integration Easy Difficult
Driver & Design Support
For support please contact the Microchip support ticket system. For further support including OS drivers please contact our partner Touch-Base. Touch-Base provides drivers for several OS, driver and design in support.
Tabs / Analog Resistive
Products
Documentation
Software
AR1011 UART
AR1021 SPI and I2C™
DV102011 Development Kit AR1000 Resistive Development Kit (DV102011) with 7" 4-wire touch screen
AR1100 USB and UART
AR1100 Controller Board USB and RS232
DV102012 Development Kit AR1100 Resistive Development Kit (DV102012) with 7" 5-wire touch screen

Touch and Input Sensing Video Channel