Touchscreens have quickly become one of our most pervasive human/machine interfaces. From smartphones to vehicle infotainment screens to factory control equipment, a variety of systems include touchscreens that respond to the moves of our fingertips. We’re now starting to see designers enhance user interfaces with more advanced technologies, such as voice and gesture recognition and, most notably, force sensing.
Force sensing, also known as 3D sensing, allows touchscreens to sense where we are touching and with how much force. Apple has already integrated force sensing interfaces in its smartwatch, laptop, and smartphone products. And we can see this technology making a big impact in application areas such as automotive, industrial automation, medical, and gaming.
According to Mordor Intelligence, the global force sensors market will grow to $2.47 billion by the end of 2020, up from $1.84 billion in 2014. To ease the process for integrating force sensing into designs, Maxim offers an industrial smart force sensor reference design. The MAXREFDES82# reference design measures force position and force magnitude, supporting applications such as 3D human interface input devices, battery-powered instrumentation, and industrial control and measurement. Learn more about how the smart force sensor reference design can save you time and effort by reading this MAXREFDES82# article, which also includes a link to a video showing the reference design in action.
As you can see from Figure 1, the smart force sensor reference design features a thin-film transistor (TFT) LCD module that shows, digitally, the forces on each of the individual load cells at each corner of the design, as well as the total force applied on the top plate. A key component of this design is the MAX11254 24-bit, 6-channel, 64ksps delta-sigma analog-to-digital converter (ADC) with SPI interface. The ADC delivers high performance with low power consumption.