Renesas MCUs implement touch sensors for IoT

  • October 23, 2024
  • Steve Rogerson

Japanese electronics giant Renesas has developed microcontrollers (MCUs) that help designers implement water-resistant touch sensors for IoT applications such as home appliances, building and factory automation, smart locks, e-bikes, and mobile thermal printers.

The RX261 and RX260 64MHz MCUs deliver power efficiency of 69μA/MHz during active operation and 1μA in standby mode. They let designers easily implement water-resistant capacitive touch sensors and deliver robust security.

They are based on the firm’s RXv3 CPU core, enabling 355CoreMark at 64MHz. This score is 2.5 times higher than competing 64MHz class MCUs. Compared with other 64MHz class MCUs, they also deliver 25 per cent lower active current and 87 per cent lower standby current. This power efficiency reduces current consumption during intermittent operation. These low power features help users meet strict energy regulations for home appliances and extend the operating time of battery-powered applications.

Renesas’ third-generation capacitive touch IP (CTSU2SL) delivers high noise immunity and water resistance, allowing users to implement touch sensors in kitchen appliances and outdoor equipment such as smart locks. The automatic judgement function reduces current consumption during intermittent operation by enabling touch detections even in standby state. The QE for Capacitive Touch tuning tool, design guides and sample programmes ease the implementation of touch sensors in multiple applications.

Many consumer and industrial systems offer wireless connectivity features such as Bluetooth and wifi to enable smartphone controls or to download firmware from cloud servers. By implementing security features with the Renesas Secure IP (RSIP-E11A) and flash protection functions, users can protect their applications from unauthorised use such as data falsification and eavesdropping by attackers. Sample programmes help users implement secure boot and secure firmware update functions quickly and easily.

Features include a full-speed USB function controller with a high-speed on-chip oscillator that eliminates the need for external crystals to generate an accurate USB clock. A Can-FD module enables fast and reliable communications. They include 8kbyte data flash enabling users to eliminate the need for an external EEPROM.

“The RX130 and 230 have seen great market success, and the new RX260 and 261 products provide an upgrade path with an advanced RX CPU core and enhanced performance and peripherals based on customer requests,” said Daryl Khoo, vice president at Renesas. “We have built a great relationship with RX customers around the world based on Renesas MCU core technology and years of innovation, including patented technology. The RX MCUs have established a unique place in the industry, and Renesas will continue to develop RX products as long as our customers want them.”

The RX261 (www.renesas.com/RX261) and RX260 (www.renesas.com/RX260) MCUs and multiple evaluation kits are available from Renesas and authorised distributors.

For more information about Renesas MCUs, visit www.renesas.com/MCUs.