Silicon Labs has introduced what it says is the industry’s most energy-efficient capacitive sensing microcontrollers (MCUs) for human-machine interfaces (HMI). The C8051F97x MCU family combines Silicon Labs’ ultra-low-power technology with accurate capacitive sensing to provide a best-in-class touch control solution for the Internet of Things, home/building automation, consumer and industrial markets.
The F97x MCUs target 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.
According to Silicon Labs the F97x MCU offers 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 is able to provide low energy consumption and improved levels of system performance. Its fast two-microsecond wake time minimises energy consumption while transitioning from sleep to active mode. The F97x MCU also 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.
The F97x MCU family offers industry-leading capacitive sensing technology with sub-micro-amp (<1 µA) wake-on-touch average current, 16-bit resolution and unmatched 100:1 dynamic range to support buttons, sliders, wheels, and capacitive proximity sensing with up to 43 channels and multiple scanning modes. The F97x incorporate Silicon Labs’ SAR charge-timing capacitance-to-digital converter (CDC) technology. The high-resolution CDC’s 40 microsecond acquisition time enables the industry’s fastest capacitive touch-sense capability without sacrificing sensitivity performance.
Silicon Labs’ CDC technology offers superior noise immunity for reliable performance in challenging conditions and configurations such as thick laminate overlays, electrical noise or variances in printed circuit board (PCB) manufacturing. This advanced CDC hardware implementation is capable of measuring capacitance on a wide range of materials including PCBs, flex circuits, and indium tin oxide (ITO) on glass and film.
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.