Accelerate EMI Qualification of Automotive Touchscreens with New Capacitive Touch Controllers

Published  June 28, 2019   0
maXTouch® TD family of touchscreen controllers significantly increases signal-to-noise ratio in nine- to 20-inch touchscreens

Microchip has released three new maXTouch touchscreen controllers to address electromagnetic interference (EMI) and electromagnetic compatibility (EMC) challenges faced by developers of automotive touchscreens. The new TD family of touch controllers comes with new differential mutual signal acquisition method that significantly increases the Signal-to-Noise Ratio (SNR). This result in the multi-finger thick gloved touch support up to the equivalence of 4.5 mm polymethyl methacrylate (PMMA). The series comprises MXT1067TD, MXT1189TD and MXT1665TD devices which are comprehensive automotive touchscreen controller portfolio in the touchscreens segment.

 

Features 

  • Features a unique waveform shaping capability: This optimizes the performance of the touch controller’s radiated emissions through an EMI optimization tool.
  • Communication via a I2C serial interface up to 1MHz
  • Support multiple thick glove (5mm) touches
  • Support thick lens (up to 3mm plastic)
  • Superior moisture performance
  • Up to 16 touch keys

The devices are fully automotive-qualified (Grade 2) and operating temperature ranges from -40 to +105 degC. The devices can support up to 16 concurrent touches in real time with touch size reporting. The devices feature great touch response which is greater than 250Hz and supports nodes from 1066 up to 1664.

 

For development, developers can take advantage of an evaluation kit which is available for each of the parts in the new maXTouch touchscreen controller family. Kit numbers are ATEVK-MXT1067TDAT-A (I2C), ATEVK-MXT1189TDAT-A (I2C), ATEVK-MXT1189TDAT-C (SPI), ATEVK-MXT1665TDAT-A (I2C) and ATEVK-MXT1665TDAT-C (SPI). Each kit includes a Printed Circuit Board (PCB) with the maXTouch touchscreen controller, a touch sensor on a clear glass lens, the Flat Printed Circuit (FPC) to connect to the sensor, a bridge PCB to connect the kit to the host computer via USB, as well as cables, software and documentation.

 

The samples and volume quantities of MXT1067TD, MXT1189TD and MXT1665TD devices are available now in TQFP128 (MXT1067TD only) and LQFP144 packages and also optimization services are now available from Microchip Technology. Pricing can be get upon request and evaluation kits are available from purchasing portal or Microchip authorized distributor.  More information available from Microchip sales representative, authorized worldwide distributor or visit Microchip’s website.