Ease-of-Integration and Robust Noise Rejection Technology Mark SMSC's Entrance into the Capacitive Sensor Market with a new line of Capacitive Sensors.

SMSC announces a new line of capacitive sensors featuring its proprietary RightTouch™ technology. Addressing the needs of system designers, the seven-member family sets a new standard in its ability to simplify development and improve noise immunity in a variety of products including notebook computers, LCD monitors, printers and household appliances. The capacitive sensor family is made up of the CAP1014, CAP1088, CAP1066, CAP1028, CAP1026, CAP1006 and CAP1005, which provide systems with a wide variety of slider, button, proximity and LED driver functionality.

Unlike commonly used microcontrollers that have no set identity and complicated programming processes, SMSC’s new capacitive sensor family is a dedicated register-based solution, with an easy three-step tuning process that does not need flash memory pre-programming. As a result, this application-specific family enables system designers to get to market quickly while keeping product development costs down. Additionally, each member of the RightTouch family comes standard with world-class 8kV ESD protection. Increased ESD coverage is required to protect against external environmental elements; most competitive solutions ship today with only 2kV protection, putting sensor technology at risk.

“SMSC is a proven leader in connectivity solutions. With the introduction of capacitive sensing technology, SMSC is expanding its industry position by addressing the connection between people and systems,” said Mark Beadle, Vice President and General Manager of SMSC’s Analog Product Line. “Using its analog expertise, SMSC designed the RightTouch family to improve upon the deficiencies of other capacitive sensing solutions on the market by providing a robust solution with respect to system noise and ease of use.”

The RightTouch architecture inherently rejects analog noise which yields a higher signal-to-noise ratio and makes fine-tuning touch thresholds easier. This family of devices has been created to minimize noise from inverters, DC-DC switching regulators and wireless frequencies. As a result, small changes in capacitance can be better detected, results analyzed and determinations made as to whether or not a touch took place. Devices with poor inherent noise rejection require additional digital filtering algorithms to be programmed into the microcontroller – adding to design time and resulting in higher costs. This higher level of noise performance enables SMSC devices to be used as proximity detectors, which detect the small capacitance of an approaching finger, while ignoring other extraneous signals.

Another key feature of RightTouch technology is its ability to constantly adapt to a changing environment. Because different circuit board suppliers and assembly manufacturers have different parasitic capacitance levels among their products, touch thresholds often vary between vendors. In a unique fashion, RightTouch devices compensate for these variances, independent of the manufacturer, thus allowing the presence of multiple suppliers on the same board. In addition, each device has the ability to recalibrate itself over time to compensate for foreign material or contaminants that find their way onto a system. This prevents false touches and maximizes performance.