Top processors for IoT designs

As IoT devices continue to proliferate across industries, chipmakers need to keep pace with changing requirements that call for higher performance, more features, improved security and better software tools. They also need to keep up with new and emerging standards and offer greater flexibility, enabling designers to select the best processors for their IoT designs.

So what is high on the developer’s agenda for processor selection? In a sneak peek at embedded.com’s 2023 Embedded Survey, several requirements top the list of selection criteria for processors: chip performance (85%), on-chip I/O or peripherals (85%), software development tools (85%) and debug support (81%).

The survey also finds that 47% of respondents choose a different processor from the one used in their previous projects. The key reasons cited for the switch: better features (40%), better future growth path/roadmap (27%), previous processor no longer available (23%), previous processor is too slow (18%) and new processor has better software development tools (18%).

Here is a sampling of the latest processors, including microprocessors (MPUs), microcontrollers (MCUs) and systems-on-chip (SoCs) that can be used in IoT applications that meet the above criteria.

Let’s start with Matter-enabled devices. The Matter standard, developed within the Connectivity Standards Alliance, enables all devices to communicate seamlessly and securely in smart-home applications.

NXP Semiconductors has expanded its portfolio of Matter-enabled solutions for smart-home devices with two new wireless MCUs. The RW612 and the K32W148 wireless MCUs combine advanced edge processing capabilities and integrated security to streamline development, simplify IoT designs and reduce costs for Matter-enabled smart-home devices. Both devices are sampling now.

The RW612 is the industry’s first secure tri-radio wireless MCU, according to NXP. The RW612 is integrated with an i.MX RT crossover MCU, which simplifies design by supporting the Matter standard. The wireless MCU features concurrent, multi-protocol support for Wi-Fi 6, Bluetooth Low Energy 5.3 and 802.15.4 and supports Thread or Zigbee. Smart-home applications include thermostats, garage door openers, door locks, IP cameras, robotic vacuums and smart appliances.

Leveraging an integrated tri-radio and advanced edge processing capabilities from the EdgeVerse i.MX RT crossover MCU family, the RW612 features an Arm Cortex-M33 MCU subsystem with TrustZone-M. The wireless MCU also includes on-chip SRAM and high-performance configurable peripherals including Ethernet, an LCD controller and five FlexComm modules to support a variety of serial protocols. The RW612 is supported by the unified MCUXpresso development environment to reduce time to market.

The K32W148 multi-protocol wireless MCU, featuring a tri-core architecture, also features advanced processing capabilities with multi-protocol enablement across Thread, Bluetooth Low Energy 5.3 and Zigbee for devices like smart plugs, smart lighting and low-power smart devices and sensors. Multi-protocol enablement reduces costs and simplifies antenna design with a single antenna configuration, NXP said.

The K32W148 includes dual-PAN capability to simplify the coexistence of multiple IEEE 802.15.4 networks like Thread and Zigbee. Built with separated radio and security execution environments, the wireless MCU’s main Arm Cortex-M33 core and memory are available for the customer’s application. Like the RW612, it is also supported by the unified MCUXpresso development environment.

Both wireless MCUs are part of NXP’s EdgeLock Assurance program, a secure-by-design approach, which includes protection against remote and local software attacks. It supports secure boot, secure debug and secure over-the-air (OTA) firmware updates, with an immutable root of trust (RoT), hardware-accelerated cryptography and life-cycle management.

They also work with the EdgeLock SE05x secure element and EdgeLock A5000 secure authenticator. These discrete security components with optionally pre-injected keys and certificates provide a Common Criteria EAL6+ certified turnkey plug-in solution, which delivers additional tamper resistance and support for additional security use cases (such as device integrity protection or secure ultra-wideband ranging), NXP said. Both devices also support the NXP EdgeLock 2GO service for provisioning and management of device credentials from manufacturing and through the device life cycle.

Also targeting smart-home applications like home appliances, intelligent lighting and smart doors and locks, as well as industrial automation including HVAC sensors and controls and motor control, is Microchip Technology’s PIC32CX-BZ2 wireless MCU family, which features Bluetooth LE, Zigbee and OTA update capabilities. It also delivers premium analog performance and complete design support.

Introducing its first Arm Cortex-M4F–based PIC MCU family, the PIC32CX-BZ2 devices include SoC devices as well as Global Regulatory–certified, RF-ready modules. Key features include a 12-bit analog-to-digital converter (ADC), multiple timers/counters for control channels, an on-board encryption engine and a broad set of interfaces for touch, CAN, sensor, display and other peripherals.

The family also provides 1 MB of flash memory, which supports large application codes, multiprotocol wireless stacks and OTA updates. The packages are AEC-Q100 Grade 1 (125°C)–qualified.

For design support, Microchip offers the MPLAB Harmony 32-bit embedded software development framework. The MPLAB Harmony v3 framework includes a variety of tools and an ecosystem of debuggers, programmers, virtual sniffers and compilers. Other support includes GitHub demo applications and documentation and wireless design check services to help with the application development process.

One of those tools is the MPLAB Code Configurator, which enables developers to quickly begin prototyping with the PIC32CX-BZ2 family using drag-and-drop auto code generation. A variety of application code examples are hosted on GitHub and linked through the MPLAB Code Configurator and MPLAB Discover.

For easier RF design, Microchip also offers pre-certified WBZ451 modules for customers with little to no RF expertise. The WBZ451PE-I and the WBZ451UE-I modules come with an on-board PCB antenna and a U.FL connector for an external antenna, respectively.

Available now, the PIC32CX1012BZ25048-I and PIC32CX1012BZ25048-E SoCs are housed in 7 × 7-mm 48 quad-flat no-lead (QFN) packages. They are supported by the PIC32CX-BZ2 and WBZ451 Curiosity Development Board (part number: EV96B94A).

Another wireless MCU family tailored for IoT devices is STMicroelectronics’ STM32WBA52 wireless MCUs with SESIP3 security. The STM32WBA52 offers a broad range of peripherals familiar to STM32 developers. They also feature Bluetooth LE 5.3 connectivity with ultra-low–power modes and advanced security.

These devices are designed for IoT device developers who are looking to add wireless, reduce power consumption, improve cyber-protection and boost processing in the edge, ST said. Target applications include smart home, industrial lighting, sensors, electrical switches, gateways and portable medical devices.

Built on the foundation of ST’s ultra-low–power STM32WB MCUs, the new device offers higher performance, with an Arm Cortex-M33 core operating at 100 MHz for extra computing power and advanced STM32 peripherals. It can support up to 20 simultaneous connections.

Other features include an integrated ultra-low–power radio with RF output power of 10 dBm, enabling reliable communication over long distances at data rates up to 2 Mbits/s and a deep standby low-power mode with active radio communication for overall reduced power and battery savings.

Energy-saving technologies, also shared with the STM32U5 MCUs, include ST’s Low Power DMA and flexible power-saving states with fast wakeup times. These features can cut MCU power by up to 90%, according to ST.

The integrated peripherals include a 12-bit ADC for enhanced accuracy with oversampling capability and error-code correction (ECC) on internal flash and RAM for enhanced data integrity and safety. It also includes 1-Mbyte flash memory for storage of the user application and protocol stacks.

The improved security includes the PSA security program based on security isolation, memory protection, tamper protection and the Cortex-M33 with the Arm TrustZone architecture. The platform provides a secure software solution based on Trusted Firmware for the Arm Cortex-M (TF-M). The TF-M meets the industry-standard PSA Certified security framework, with PSA immutable RoT including secure boot and secure firmware update, cryptography, secure storage and attestation at runtime, ST said.

It also includes embedded side-channel–resistant symmetric and asymmetric cryptographic accelerators, and key protection is implemented using a hardware-unique–key secure process. The STM32WBA52 product line targets Arm PSA Certified Level 3 and SESIP3 IoT security standards, ST said.

Another benefit for developers is the STM32Cube ecosystem, which simplifies the migration from existing STM32WB and general-purpose STM32 MCUs and accelerates application development and validation. It features the STM32CubeWBA MCU package, embeds a certified Bluetooth LE 5.3 protocol stack and builds on existing profiles from the STM32WB series. It also includes tools like the STM32CubeMX peripherals configurator and code generator, STM32CubeMonitor-RF radio-performance tester and STM32Cube.AI desktop and cloud versions for AI.

Samples are now available in the UFQFPN48 package. A dedicated Nucleo prototyping board, NUCLEO-WBA52CG, will be available for the STM32WBA52. In addition, the STM32WBA52 MCUs will be included in ST’s 10-year product-longevity program.

ST also expanded its STM32U5 series with improved performance and energy efficiency for IoT and embedded applications. These devices are also the first general-purpose MCUs to receive U.S. National Institute of Standards and Technology (NIST) embedded random-number entropy source certification, the company said.

The new devices target applications that require higher functionality, better graphics, faster performance and a longer runtime using a smaller battery or energy harvesting. They can be used in embedded applications like environmental sensors, industrial actuators, building automation, smart appliances, wearable devices and e-mobility controls, especially in remote and difficult-to-access locations, ST said.

The new MCUs extend the range of code and data storage to 128-Kbyte flash for cost-sensitive applications and add high-density versions for complex applications and smartphone-like user interfaces. One example is the STM32U59x/5Ax with 4-Mbyte flash and 2.5-Mbyte SRAM, which offers the largest on-chip memory of any STM32 MCU.

“The large on-chip memory saves additional discrete memory chips that otherwise increase power consumption, bill-of-materials cost and PCB size,” ST said.

The devices also incorporate proprietary energy-saving features, including autonomous peripherals and ST’s low-power background autonomous mode.

Some of the devices in the series provide a 2.5D graphics accelerator. Variants with ST’s advanced NeoChrom graphics processing unit on-chip can run a sophisticated graphical user interface previously only possible with an expensive MPU-based system, according to the company.

In terms of security, the MCUs integrate cryptographic accelerators for advanced AES algorithms, support for public key architecture and resistance to physical attacks. In addition, the ECC for flash and SRAM memory prevents corruption, which enhances both cyber-protection and safety, ST said.

Like other STM32 MCUs, these are based on industry-standard Arm Cortex-M embedded CPU cores. The new devices incorporate the latest-generation Cortex-M33 that offers higher performance, higher energy efficiency and increased resistance to online and hardware attacks. They also leverage the STM32Cube and STM32Cube.AI development ecosystem, along with other resources like the new NUCLEO-U545RE and NUCLEO-U5A5ZJ development boards and the STM32U5A9J-DK Discovery kit for graphics. The new STM32U5 devices are scheduled to begin volume production in the second quarter of 2023.

Renesas Electronics Corp. offers several series of RA MCUs—RA6, RA4, RA2 and the upcoming series based on the Arm Cortex-M85—for a range of IoT applications, including home appliances, healthcare, metering and industrial and building automation. The latest devices in the RA family of MCUs deliver high performance, high power efficiency and security in a small package. The company expanded its 32-bit RA MCU family with two new entry-line groups based on the Arm Cortex-M33 core with Arm TrustZone technology.

The new 100-MHz RA4E2 Group and 200-MHz RA6E2 Group offer 128-Kbyte and 256-Kbyte flash options and 40 Kbytes of SRAM with lots of connectivity options, such as on-chip CAN FD, USB, QSPI, SSI and I³C interfaces. They offer an upgrade path to other members of the RA family and are suited for a range of applications like sensing, gaming, wearables and appliances thanks to their high performance in small packages.

Renesas said that the RA4E2 and the RA6E2 are the most cost-effective RA devices with integrated CAN FD and are available in a 4 × 4-mm 36-pin BGA and a 5 × 5-mm 32-pin QFN. They also offer low power consumption for energy savings.

Featuring a 100-MHz Arm Cortex-M33 CPU core, the RA4E2 Group includes five different options, spanning from 32-pin to 64-pin packages as small as 4 × 4 mm, and 128 kB of flash memory and 40 kB of SRAM. Power consumption is 82 µA/MHz while executing from flash at 100 MHz. The extended operating temperature range is –40°C to 105°C. Other features include an internal oscillator, advanced analog, low-voltage detection and internal reset function, along with lots of GPIOs and communications options, including USB 2.0 Full-Speed Device, SCI, SPI, I³C, HDMI CEC, SSI and CAN FD.

The RA6E2 Group MCUs feature a 200-MHz Arm Cortex-M33 CPU core. The group includes 10 parts and, similar to the RA4E2, offers options spanning from 32-pin to 64-pin packages as small as 4 × 4 mm, 128 kB to 256 kB of flash memory and 40 kB of SRAM. They offer extensive peripherals, including an integrated timer, advanced analog and connectivity options, including USB 2.0 Full-Speed Device, SCI, SPI, I³C, HDMI CEC, SSI, QSPI and CAN FD. Power consumption is 80 µA/MHz while executing from flash at 200 MHz.

All RA devices are supported by the Renesas Flexible Software Package (FSP) that includes drivers and middleware for easier implementation of communications and to improve the functionality of peripherals. With FSP use, designers also have access to the full Arm ecosystem as well as Renesas’s partner network for a wide range of tools.

All the new RA4E2 and RA6E2 MCUs are available now along with separate evaluation kits and fast prototyping boards.

Renesas also recently launched its new online cloud-based IoT system design platform, built on its Quick-Connect IoT, a platform of standardized hardware featuring industry-standard interfaces like PMOD, Arduino and MIKROE. With the new Quick-Connect Studio, engineers can develop hardware and software simultaneously, enabling them to graphically build hardware and software. This allows engineers to quickly validate prototypes and accelerate product development, and by enabling them to build the software immediately, it allows them to reconfigure and test products faster, Renesas said.

Aimed at the connected intelligent edge, Qualcomm Technologies Inc. recently claimed the first integrated 5G IoT processors that support four major operating systems, along with two new robotics platforms and an accelerator program for IoT ecosystem partners.

The upgraded high-tier SoCs, the QCS6490 and QCM6490 processors, target a range of IoT industrial applications and can now run Linux, Ubuntu and Microsoft Windows IoT Enterprise, in addition to Android. They offer advanced features like 5G support for global connectivity and geolocation for a range of solutions, including connected camera devices like dashcams, edge boxes, industrial automation equipment (IPC, PLC) and autonomous mobile robotics.

Qualcomm also introduced the new scalable QCM5430 and QCS5430 processors, which are the company’s first software-defined IoT solutions. These devices can scale across a range of IoT devices and deployment configurations in a visual environment and offer several OS options.

Aimed at applications like industrial handheld devices, retail equipment, mid-tier robots and connected cameras and AI edge boxes, these platforms give designers a choice between premium, pre-set or customized feature packs, which can then be upgraded in the future.

They support up to five concurrent cameras and video encoding at up to 4K 60 fps and are ready to support machine-vision requirements with low-power and advanced edge AI processing, Qualcomm said, and when needed, the edge AI can switch to cloud processing for handling multiple camera connections, optimizing between response time and power efficiency. They also support enterprise-grade on-device security.

Both pre-set platform packages—QCM5430/QCS5430 Feature Pack 1 and QCM5430/QCS5430 Feature Pack 2—include premium connectivity. Wi-Fi support includes 802.11ax (Wi-Fi 6E) with transmit speeds up to 3.6 Gbits/s and other enhancements, such as reduced latency. The connectivity suite on the QCM5430 processor includes a 5G modem that supports millimeter-wave connectivity for ultra-fast data and highly precise geolocation. The wired connectivity options start with a single USB 3.1 port and one PCIe port and can be configured for up to two PCIe and a 4K60 display port, as well as other options.

The upgraded Feature Pack 2 offers increased CPU performance and interface support, while a variety of scalable and upgradable options are available as part of the QCM5430/QCS5430 Custom Feature Pack, including support up to 4K 60-fps video and up to a triple ISP camera.