Semtech debuts 4-dimensional touch

CAMARILLO, USA: Semtech Corp., a leading supplier of analog and mixed-signal semiconductors, announced the newest members of its 4-D Touch family, the SX8654/55/56/57/58 ultra low power 4/5-wire resistive touchscreen controllers with integrated proximity sensing and haptics control for driving motors.

These feature-rich controllers also come with on-chip ±15kV ESD protection making them ideal solutions for a wide variety of handheld applications such as mobile phone, tablet, DSC, handheld GPS, automotive center consoles, and POS terminals.

Many devices use the proximity of a person’s hand or finger to activate features, such as waking up a system. The SX865X controllers are the first to integrate this proximity capability into a touchscreen controller to provide a single-chip solution for a wide variety of applications such as mobile phone, tablet, DSC, handheld GPS, automotive center consoles, and POS terminals.

This resistive touchscreen controller platform supports a proximity detection distance of more than 5 cm using any standard 4/5-wire resistive panel, enabling various power-saving features such as automatic backlight activation or system wake-up. Unlike traditional IR solutions that require additional, costly components for proximity detection, this new generation of resistive touch screen controllers enables proximity detection with zero additional components.

The SX8654/55/56/57/58 feature a highly accurate 12-bit analog-to-digital converter for coordinates and touch pressure measurement with current consumption as little as 30uA at 8kSPS rate. The SX8654 family enters a low power state between conversions to save power consumption, making them ideal for portable applications.

These devices also incorporate a haptics motor driver for controlling Linear Resonant Actuator (LRA) and Eccentric Rotating Mass (ERM) micro motors (up to 250mA) while providing acknowledgement to touch events, thus emulating the tactile feedback similar to mechanical keys which enhances the overall user experience. The haptics waveform can be input via the I2C interface or with an external PWM signal. Immersion Corp. has certified the SX8657/58 as optimal motor drivers for its TouchSense 3000 haptic control software suite of haptic waveforms available to all customers via an Immersion license.

“The SX8654 family is a ground-breaking platform for resistive touchscreen applications. By enabling built-in proximity sensing using any resistive panel, Semtech has added especially expensive high-end features at the fraction of the cost of traditional IR proximity sensing,” said Sam Massih, product line director, Consumer Analog Products. “Combining that with direct drive haptics feedback, the SX8654 platform provides OEMs an opportunity to revolutionize and upgrade almost all their resistive touchscreen applications with value added features.”

The SX8654/55/56/57/58 are all offered in 4mm x 4mm 20-QFN packages as well as in a space-saving 2.07mm x 2.07mm 19-WLCSP. Semtech guarantees all of these devices to operate over the extended (-40°C to +85°C) temperature range.