Silicon Laboratories combines capacitive and IR proximity sensing

CAMBRIDGE, UK — With its QuickSense portfolio, Silicon Laboratories Inc., launched three new products aimed at the human interface market, supporting accurate and fast-response touch, proximity and ambient light sensing within a common development environment.

The company’s mixed-signal intellectual property is the foundation for a portfolio of human interface technologies encompassing infrared, capacitive touch sense, high-performance processing and low-power design.

The QuickSense portfolio includes the Si11xx family of proximity and ambient light sensors, the C8051F800 family of capacitive touch sense MCUs, expanding C8051F7xx family of capacitive touch sense MCUs, and the development suite QuickSense Studio.

The QuickSense Si1102 sensor enables an electronic device to quickly gauge its proximity to the user. For example, it can detect if a handset is near a user’s face and adjusts the display and lighting accordingly. The Si1120 infrared proximity and ambient light sensor can also detect the ambient light in the external environment, allowing screen backlighting to be dimmed, for example, saving power.

When paired with the F700 and F800 touch sense MCUs, the devices enable smart motion sensing, giving designers a complete array of human interface technologies for their applications.

Unlike competing approaches that require the infrared LED to be pulsed multiple times over a long period for accurate measurements, the Si1102/20 devices use a patented single-pulse proximity measurement technique to achieve up to a 4000x improvement in power efficiency.

With up to a 50 cm range, the Si1102/20 can easily power down displays and other functions when the user is not present. This power-saving capability is particularly appropriate for products such as appliances, security panels and IP phones.

The Si1120 device makes possible the design of touchless proximity sliders for gesturing, allowing end users to navigate without a physical touch but with simple gestures. The high sensitivity that enables this touchless control feature offers robust performance under a wide range of lighting conditions. Low-cost or low-profile infrared LEDs can be used.

The F800 MCU family comes with a patent-pending capacitance-to-digital converter (CDC) for optimum touch sensing. The high-resolution CDC, which features a 40 microsecond acquisition time combined with a 25 MIPS CPU, provides sophisticated and highly responsive touch sense functions to replace mechanical buttons, sliders and wheels.

Advanced 16-bit resolution enables the CDC and firmware to compensate for changes in geometry and laminates that may occur between prototyping and production, making the F800 MCUs accurate but forgiving and improving end-product reliability. The CDC requires very little CPU overhead, allowing the MCU to perform other tasks and improving system efficiency.

To wrap up these announcements, a QuickSense Studio configuration wizard (freely available) allows designers to select which functions they want implemented such as capacitive touch sense buttons, sliders and wheels, and then easily auto-generate the software to set up and calibrate these functions.

A low-cost development kit, the C8051F800DK includes everything required to immediately begin system design including the QuickSense Studio, IDE, target board, cables and power supply.

Reference designs and evaluation boards are also available at www.silabs.com/pr/QuickSense.