MCUs Replace Sensors In Capacitance Measurement Apps

Renesas Electronics launches its Material Detection Solution, which the company claims can detect materials or liquids easily and cost effectively without sensors by connecting electrodes using its RX130 capacitive touch-key microcontrollers (MCUs). Reportedly, by replacing the sensors with this electrode approach contributes to lower bill of materials (BOM) costs while enabling detection at multiple points using a single chip.

The touch-key MCUs feature a capacitive touch sensor unit specialized for capacitance measurement with extremely high sensitivity and high noise resistance. This enables the Material Detection Solution to easily detect the presence or absence of a powder such as vacuum cleaner dust, a liquid, or material such as paper by measuring the capacitance between electrodes to the MCU. The increase or decrease of the powder, liquid, or material will change the capacitance value between the electrodes.

The Renesas solution connects two thin-film electrodes and measures the capacitance between those electrodes using one of its touch-key MCUs. Changes in the measured materials are determined by detecting the change in capacitance between the electrodes.

In addition to eliminating the need for sensor evaluation and operating condition determination, the initialization and sensitivity adjustments can be performed using the development support graphical user interface (GUI) tool available for capacitive touch sensor systems. The solution includes design support materials such as electrode-interface circuit diagrams, a sample program, and guidelines for the newly implemented detection function.

The Material Detection Solution is available now for free download. Also, you can learn more about the Renesas' capacitive touch key solutions.