Atmel has rolled out a new maXTouch family to facilitate single-layer shieldless designs in automotive center stacks, navigation systems, radio interfaces and rear seat entertainment platforms.
“The mXT336S is optimized for 7-inch touchscreens, while the mXT224S targets smaller touchscreens and tablets,” said Stephan Thaler, Atmel Marketing Director for Automotive Touch Products. “Both are AEC-Q100-compliant and fully automotive qualified.”
Dedicated firmware and a high signal-to-noise ratio makes these devices ideally suited for very noisy environments. Since only a high signal-to-noise ratio enables detection of touches with a “gloved” finger, the devices provide full support for gloved hand operation on automotive touchscreens.
As Thaler notes, conventional touch controllers are unable to handle LCD noise, so an additional shield layer is typically required to prevent noise coupling.
“However, thanks to the [optimized] noise handling and filtering capabilities of our new automotive- qualified maXTouch devices, shields are no longer required, and designers can use single-layer sensors instead of dual or triple layers, which are typical in many current applications,” he explained.
“By eliminating an additional layer, designers have a thinner stack which reduces the overall system complexity, lowering the overall cost and power consumption, which results in higher yields during production.”
Indeed, the mXT336S/mXT224S devices support touch detection, up to 10 simultaneous touches, touch size reporting, single- and dual-touch gesture calculation, communication of X/Y positions, gesture support and the ability to eliminate unintended touches. Users can also perform multi-touch gestures (pinch, stretch, etc.), while unintended touches are rejected, such as a resting hand on the screen. Simply put, the above-mentioned key features help bring the smartphone experience into contemporary cars.
Samples of the automotive-qualified mXT336S and mXT224S touch controllers are currently available in TQFP64 packages, while demo kits for both devices can also be ordered to support design-in and shorten time-to-market.
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