MCUs Deliver Hardware-Based IoT Security

Security is suddenly a hot topic. It’s unsurprising, given all the talk about connecting devices and implementing Internet of Things (IoT) devices, coupled with more awareness of the potential threats from cyber-attacks. Recognizing this, STMicroelectronics and NXP Semiconductors have both launched microcontrollers utilizing the Arm Cortex-M33 integrating TrustZone to enable greater IoT security.

STMicroelectronics this week launched the STM32L5 microcontroller, which builds on the Cortex-M33 hardware-based security with its own enhancements such as flexible software isolation, secure boot, key storage and hardware cryptographic accelerators. It is aimed at power conscious connected devices, utilizing the company’s expertise in low-power techniques such as adaptive voltage scaling, real-time acceleration, power gating and multiple reduced-power operating modes proven in previous STM32L series. This enables it to provide long run-times powered by coin cells or energy harvesting, consuming as little as 33nA in shutdown mode and achieving 402 ULPMark-CP in the EEMBC ULPBench.

Meanwhile, NXP launched its LPC5500 series single and dual-core 100MHz Arm Cortex-M33 microcontrollers in 40nm flash technology for a range of industrial and IoT edge applications. The company says it combines hardened security subsystems and software into a secure execution environment (SEE). Its’ LPC55S69 devices achieve 32uA/MHz efficiency at up to 100 MHz core clock frequency, dual-core Cortex-M33 capability with additional tightly coupled accelerators for signal processing and cryptography, and up to 640KB Flash and 320KB on-chip SRAM for advanced edge applications.

Matt Short, senior director for IoT at IHS Markit, said it was good to see security coming to the top of the agenda. He said all the chip vendors are talking to the same customers who are all expressing concern about security.

“With IoT, security has now become a must have,” Short said. “It’s good to see security and trust being a topic of conversation, even down at the microcontroller level.  A hardware root of trust is essential. STMicro stayed in a 90nm process and optimized for power consumption, using a more mature process and using some circuit design techniques to significantly reduce battery power. Maybe there’s a cost advantage for 90nm, too. On the other hand, NXP opted for performance in a 40nm process.”

In general, Short said, it’s a good move for ST to optimize for battery power over processor performance. But he said the real differentiation for ST, NXP and other companies comes in the the ecosystems they build around the microcontroller.

“The conversation is gradually shifting from hardware and software to partnerships and ecosystems,” Short said. – EE Times