Renesas R8C/33T Capacitive Touch Microcontrollers

Renesas Technology America introduced the R8C/33T microcontrollers (MCUs). The R8C/33T MCUs include an on-chip Sensor Control Unit (SCU) for capacitive-touch applications. The R8C/33T microcontrollers combine the features of Renesas’ R8C family with touch-sensor technology from OMRON. The capacitive touch microcontrollers feature 18 independent capacitive-touch channels, a range of peripheral functions, up to 32KB of on-chip flash memory, and 4KB of data flash memory with background operation (BGO). They are ideal for embedded systems that combine enhanced user interfaces with full system control functions and capabilities. Applications include home appliances, security systems, thermostat control panels, medical devices, personal computers, audio/video components, and office equipment.

Renesas R8C/33T Microcontrollers (MCUs) for Capacitive Touch

The R8C/33T microcontrollers feature an R8C 16-bit CPU core and a data transfer controller (DTC). Peripheral functions include multiple serial interfaces, 8- and 16-bit timers, up to 12 channels of analog-to-digital conversion, and high-current ports for direct LED control. The devices support 1.8V to 5.5V operation and are packaged in a 32-pin, 7mm x 7mm LQFP.

Renesas R8C/33T Capacitive Touch Microcontrollers Features

  • High integration for lower systems cost
    Integration of an on-chip sensor control unit for a capacitive-touch sensor means that system control and touch control can both be handled by a single chip. In addition, the MCUs in the R8C/33T group can connect directly to the sensor electrodes for touch sensing. This eliminates the requirement for resistors and capacitors for each electrode; thereby, reducing the total number of parts, lowering the overall system cost, improving reliability, and shortening the product development time.

  • Approximately 1/10 the power consumption of comparable capacitive-touch MCU products
    The addition of a sensor control unit dramatically reduces the amount of CPU processing time needed for touch detection and cuts the system power consumption to about 1/10 of that when a comparable Renesas Technology MCU is used and touch detection is implemented in software. Also, the SCU operates at a low frequency (4MHz or 5MHz), which also helps to reduce power consumption. During touch-detection operation, an R8C/33T MCU can also handle other system control tasks such as LED illumination, serial communication and PWM control.

  • Improved touch-detection sensitivity
    The sensor control unit for capacitive-touch sensors employs a series-capacitance division-comparison system that provides very rapid and stable touch-detection functionality.

  • Data transfer controller
    MCUs in the R8C/33T group have an on-chip data transfer controller (DTC) that performs functions similar to those of a direct memory access controller (DMAC). The DTC unit manages data transfers from memory to memory, or memory to peripherals, without CPU intervention.

  • Workbench GUI Tool
    Essential design tasks such as electrode design, sensitivity adjustment, threshold-value setting, and signal monitoring can be performed easily, reducing development time and costs. Settings can be written to Data Flash memory to allow for fine-tuning of individual models. This makes it possible for customers to incorporate highly accurate touch-sensor solutions into their products.

More info: Renesas Technology