Please visit https://m2351.nuvoton.com/ for detailed information about Nuvoton's first IoT security Microcontroller.
The rise of the internet of things era has increased awareness for the integration of the physical world into digital systems. While the digitization of our everyday lives led to efficiency improvements and economic benefits, it has also caused pressure on systems designers who are now required to come up with innovative IoT products capable of performing secure connection and data exchange while maintaining low power consumption. Since security and power consumption are both key requirements in IoT application, Nuvoton has developed the NuMicro® M2351 Series, which excels in supporting the proliferation of intelligent connected devices.
The NuMicro® M2351 microcontroller series is powered by Arm® Cortex®-M23 core with TrustZone® for Armv8-M architecture, which elevates the traditional firmware security to a new level of robust software security.
The low-power M2351 series microcontroller operates at up to 64 MHz frequency, with up to 512 Kbytes embedded Flash memory in dual bank mode, supporting secure OTA (Over-The-Air) firmware update and up to 96 Kbytes embedded SRAM. Furthermore, the M2351 series also provides high-performance connectivity with peripheral interfaces such as UART, SPI, I²C, GPIOs, USB and ISO 7816-3 for a smart card reader. Its secure and efficient power management features strengthen the innovation of IoT security.
TrustZone® for Arm®v8-M empowered
The NuMicro® M2351 series is empowered by the Arm® TrustZone® for Armv8-M architecture. Arm® TrustZone® technology is a System on Chip (SoC) and CPU system-wide approach to security. In addition to firmware-level security, the M2351 series offers a more enhanced software-level security for robust security and greater power efficiency.
In addition to the Cortex®-M23 CPU core, the TrustZone® components of the M2351 Series include:
- Secure Attribution Unit (SAU, inside of the Cortex®-M23 CPU)
- Implementation Defined Attribution Unit (IDAU)
- Flash Memory Controller (FMC)
- Security Configuration Unit (SCU, supports SRAM and peripheral configurations)
As shown in the figure above, certain functionalities are fixated as secure attribution or allow secure access only to assure higher software-level security. Besides, other parts of the functionalities are designed to support TrustZone® implementation with bus master and bus slave IPs integration to realize the security functions.
Nuvoton® Security Functions Strengthened
In addition to TrustZone® technology, the NuMicro® M2351 series is also equipped with rich functions to improve system security. The Secure Bootloader supports trusted boot feature. The hardware crypto accelerators, including ECC, supports encryption and decryption operation to offload processor-computing power. The KPROM is a password protection mechanism to allow Flash memory write and erase. The XOM (Execute-Only-Memory) defines execute-only memory regions to protect critical program codes. The Flash lock bits are designed to disable external Flash read/ write and debug interface. Tamper detection pins can detect the state transition on the tamper pins.
Power Management Technology for IoT Innovation
Other than security, power consumption is also critical for IoT applications.. M2351 Series offers multiple power modes for more efficient power management. Regarding the power consumption of M2351 series, the normal run mode consumes 97 μA/MHz in LDO mode and 45 μA/MHz in DC-DC mode. The current consumption of standby power down mode is 2.8 μA and the deep power-down mode without VBAT is less than 2μA.