Semtech Debuts 4D-Touch™ Platform to Enhance User Experience by Sensing all Four Dimensions

These innovative touch devices integrate a proximity detection feature that gives OEMs the ability to introduce a new type of sensing experience to their products well before a user even touches the device. This high resolution capacitive proximity sensing is implemented with Semtech’s proprietary analog front-end design, which enables detection from a long distance as well as sensing through thick overlays and materials with low permittivity. This key differentiator in touch sensing will enhance the user experiences across a wide variety of applications.

Semtech’s 4D-Touch™ family includes both resistive and capacitive sensing platforms. The first resistive touchscreen products in the 4D-Touch family are the SX865X controllers that were announced on July 28, 2011. This resistive touchscreen solution supports a proximity detection distance of more than 5 cm using any standard 4/5-wire analog resistive panel.

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. These resistive touchscreen controllers not only calculate the X,Y coordinate of the touch, but also support capacitive proximity sensing (Z+) as well as pressure measurement (Z-) with tactile feedback via haptics.

Typical enhanced user experiences enabled by this type of technology includes waking up the system as the user moves within sensing range, adjusting the backlight brighter/dimmer as the user approaches the panel or even displaying hidden/key menus as the user’s hand gets close to the display. Some products in the 4D-Touch™ family also have an integrated ability to drive LRA or ERM motors directly for haptic feedback emulating the mechanical tactile feedback users are accustomed to, as well as giving the appropriate strength of haptic feedback proportional to the pressure measurement.

Semtech also offers capacitive touch-button solutions (SX8633/34/35/36/38/39/61) as part of he 4D-Touch™ brand with such high sensitivity that a hand approaching within 10cm can automatically turn on the LEDs behind the control buttons and provide visual feedback to the user. An LCD TV or monitor is an ideal application where these control buttons are typically hidden until someone reaches for them at which point they are turned on.

All of the products in Semtech’s 4D-Touch™ family have common attributes that make them technically world class and innovative. They are all architected for low power applications in portable equipment dissipating as little as 0.4uA in standby mode. Robust ESD protection as high as ±15kV ESD is also integrated on-chip to reduce the customer’s BOM cost and board space from the requirement for external ESD protection typically used in touch applications. These feature-rich devices also come in miniature form factors as small as a 2mm x2mm WCSP.

“Semtech’s 4D-Touch™ family is quite unique in the touch sensing space. This family of solutions allows sensing in all four dimensions making it so that the user doesn’t have to initiate the user experience, rather it comes to them seamlessly before the touch,” said Sam Massih, Product Line Director, Consumer Analog Products for Semtech. “Combining that with Semtech’s world class design of analog and mixed-signal circuits in the sensing, control, power, and ESD domains, the 4D-Touch™ platforms will enhance a wide range of existing capacitive and resistive touch applications already available today in many common consumer products.”