Capacitive MCUs address touch-sensing market

Products include F99x MCUs with integrated touch-sense technology for human-interface applications and F98x MCUs targeting power- and cost-sensitive applications, such as home automation, smart meters, lighting control, security systems, games and toys.

The ultra-low-power F99x and F98x MCUs are said to offer the industry's lowest power consumption in active mode, sleep mode and deep sleep mode.

The MCUs also contain an integrated low drop-out (LDO) regulator that keeps the current constant at 150 microamps per MHz over the entire operating range of 1.8 to 3.6V.

The on-chip LDO regulator is claimed to help reduce the MCUs' drain on the battery by 50 per cent compared to competing products, which extends battery life and makes the F99x and F98x MCUs ideal for battery-powered applications.

The F99x touch-sense MCUs, a part of Silicon Labs' Quicksense human-interface device range, combine ultra-low-power capabilities with fast, accurate capacitive sensing technology for the touch-sensing market.

They feature a patent-pending, high-resolution capacitance-to-digital converter (CDC) with a 40 microsecond acquisition time, enabling the industry's fastest capacitive touch-sense capability.

The CDC offers superior noise immunity for reliable performance in challenging conditions and configurations such as thick laminate overlays, electrical noise or variances in circuit-board manufacturing.

Available with up to 14 capacitive sensing inputs, the F99x MCUs support sophisticated and highly responsive touch-sense functions to replace traditional mechanical buttons, sliders and wheels.

By combining the F99x ultra-low-power MCUs with Silicon Labs' Si11xx Quicksense infrared and ambient light sensors, system designers can develop 'touchless' proximity sensing interfaces.

These enable users to control and interact with end products through simple, intuitive gestures, in addition to using direct capacitive touch-sense control.

The F99x and F98x MCUs integrate a 25MHz pipelined 8051-compatible core, a precision oscillator, a 12-bit analogue-to-digital converter (ADC), a temperature sensor, a voltage reference and four timers.

The low-power MCUs also add 2, 4 and 8 kB flash options to the F9xx range, which offers a range of footprint- and software-compatible ultra-low-power MCUs scaling up to 64kB of flash.

For added board-design flexibility, the F99x and F98x MCUs are available in standard 24-pin QFN and 24-pin QSOP packages, as well as a space-saving 20-pin 3 x 3mm QFN package option that's suitable for space-constrained applications.