Silicon Labs continues to find more markets for its 8051 based MCU architecture with the introduction this week of its C8051F97x MCU family, what it claims is the industry’s most energy-efficient capacitive sensing microcontrollers (MCUs) for human-machine interfaces (HMI).
The new MCU family is targeted mainly at touch control solution for embedded Internet of Things, home/building automation, consumer and industrial markets. But it is not ignoring the consumer altogether, also targeting it at battery-powered and capacitive touch sensing applications for handheld industrial devices, toys, gaming machines and remote controls, as well as touch-panel switch replacements for white goods such as washers, dryers, ovens and dishwashers.
Silicon Labs’ F97x MCUs offer the industry’s lowest energy consumption in active, sleep and deep-sleep modes, enabling the longest battery life of any 8-bit capacitive sensing MCUs. With 200 µA/MHz active current, the F97x MCUs provide an ideal combination of low energy consumption and excellent system performance.
The MCUs’ fast two-microsecond wake time minimizes energy consumption while transitioning from sleep to active mode. The F97x MCUs offer the lowest sleep mode energy consumption in their class: 55 nA sleep current with brownout detector enabled and 280 nA sleep current with a 16.4 kHz internal oscillator.
“Many of today’s battery-powered connected devices for the IoT require high-performance yet energy-friendly touchscreen user interfaces,” said Daniel Cooley, vice president and general manager of Silicon Labs’ microcontroller and wireless products, pointing to the F97x MCU family's sub-micro-amp (<1 µA) wake-on-touch average current, 16-bit resolution and 100:1 dynamic range to support buttons, sliders, wheels, and capacitive proximity sensing with up to 43 channels and multiple scanning modes.
He said the devices incorporate Silicon Labs’ SAR charge-timing capacitance-to-digital converter (CDC) technology to allow 40-microsecond acquisition time without sacrificing sensitivity performance.
The F97x MCU family expands the capabilities of Silicon Labs’ popular C8051F99x low-power capacitive sensing MCUs with up to 43 capacitive sensing inputs, 32 kB flash memory, 8 kB RAM, seven DMA channels and a 16 x 16 multiply-accumulate (MAC) unit in QFN packages as small as 4 mm x 4 mm. The F97x MCUs integrate a 25 MHz pipelined 8051-compatible core, a precision oscillator, a 10-bit analog-to-digital converter (ADC), a temperature sensor, a voltage reference and four 16-bit general-purpose timer/counters.
The F97x MCU family is supported by the Simplicity Studio development platform, which enables developers to quickly demonstrate and develop capacitive touch interfaces. This complimentary software platform includes a fully integrated Eclipse-based integrated development environment (IDE), a Keil compiler (supporting unlimited code size), demonstration tools, application examples, libraries and documentation in a single, simple-to-use tool.
A built-in Capacitive Sense Profiler tool, he said, greatly simplifies the fine tuning of buttons, sliders, wheels, touch pads and proximity sensors, as does a full-featured capacitive sense firmware library.
Samples and production quantities of the C8051F97x MCUs are available now.