New capacitive touch controllers

Paul Boughton

Schurter and AMT are successful partners in the field of customised touch panel solutions. Danielson, as a new member of the Schurter Group, is fully integrated into this partnership. The AMT PCAP and resistive touch sensors and controller-systems are available for the entire Schurter Group.

AMT with its PenMount PCAP controller series has now released the new boards PM1x10, which meet the EMC standards for industrial and medical applications. These certifications are a step forward to realising reliable PCAP systems in the industrial and medical market.

The fulfillment of these high EMC requirements was made possible by appropriate modifications in the design of the PCAP sensor as well as the hardware and firmware of the controller system. The firmware includes a complementary frequency-hopping with dozens of alternate frequencies to lower interference frequencies and a differential analysis method to decrease interference in the medium frequency range. The sense channels of the microcontroller from Microchip are equipped with passive filters against high-frequency interferences. To increase the signal-to-noise ratio, charge pumps have been integrated into the drive lines.