To reduce the risk of fires in the kitchen and also floods in the laundry room, European IEC 60730 and U.S. UL 60730 Class B specifications require safety mechanisms in home appliances, such as ovens, cooktops, washing machines, and clothes dryers. Helping designers meet these functional safety requirements in touch screen enabled appliances, Microchip Technology Inc. announced its maXTouch MXT336UD-MAUHA1 capacitive touchscreen controller family — the market’s only touchscreen controllers to offer pre-certified, Class B firmware. The family includes three controllers, the MXT112UD-MAUHA1, the MXT228UD-MAUHA1, and the MXT336UD-MAUHA1, each fulfilling different screen size needs, ranging from 2-to 8-inches.
The Class B certified touch controllers offer unique safety-related features that enable system shut off through an intuitive soft button on a touchscreen, removing the requirement for an external safety certified stop or cancel button and associated microcontroller (MCU). They also allow an appliance to detect a touchscreen or appliance failure and shut down automatically through a variety of self-testing capabilities. For example, if the glass breaks on a cooktop, the touchscreen will turn dark and shut off the machine, eliminating accidental damage in the home. As the number of touch-enabled home appliances continues to increase, the MXT336UD-MAUHA1 family shifts the required safety functionality to a simplified single touchscreen interface, helping OEMs reduce costs and improve time to market.
In addition, this new family leverages a high signal to noise ratio (SNR) design and proprietary differential mutual acquisition scheme. This allows the machine to reliably detect and track multiple fingers on surfaces exposed to moisture, water, grease, and more — even if the user is wearing gloves.
Software and hardware tools are available. Software tools include maXTouch Studio and maXTouch Analyzer. Hardware tools include an evaluation kit, available upon request.
The MXT336UD-MAUHA1 family is available in volume production starting at $1.82 in 10,000-unit quantities.