Wireless SoC has security features for broad IoT
Believed to be the world’s first dual Arm Cortex-M33 wireless SoC, Nordic Semiconductor’s nRF5340 is suitable for complex IoT applications including low energy audio, advanced wearables, industrial automation and professional lighting.
The nRF5340TM multi-protocol SoC combines a high performance application processor with a fully programmable, low power network processor, advanced root of trust and trusted execution security features, into a low power, multi-protocol SoC for complex IoT applications. The nRF5340 supports major RF protocols including Bluetooth 5.2 and Bluetooth Low Energy (Bluetooth LE), Bluetooth mesh, Thread, and Zigbee.
The SoC has been designed to meet the requirements of LE Audio, enabling audio streaming over Bluetooth LE. LE Audio supports multi-stream synchronised audio for applications such as earbuds, and audio sharing, in which a single audio source can be broadcast to multiple recipients. With an LE Audio- enabled software stack, the nRF5340’s radio can support isochronous channels, the Bluetooth 5.2 feature required by LE Audio for streaming. A low complexity communications codec (LC3) is also integrated for the low power audio compression codec to run efficiently on the nRF5340. The audio data can be transferred to other parts of the system (for example, ADC or DACs, speakers, and microphones) using the I2S and PDM audio interfaces, which employ the nRF5340’s low-jitter audio PLL clock source.
For security, the production version of the nRF5340 incorporates Arm CryptoCell-312, Arm TrustZone technology and secure key storage. Arm TrustZone technology provides system-wide hardware isolation for trusted software by separating between secure and non-secure regions on a single core. The security attributes of the flash memory, RAM, and peripherals are easily configured through software available in the companion nRF Connect software development kit (SDK).
The SDK is publicly hosted on GitHub, offers source code management with Git and comes with free SEGGER Embedded Studio IDE support. The SDK currently includes development support for Bluetooth LE, Thread and Zigbee, with production support coming during H1 2021.
In addition to the dual Arm Cortex-M33 processors, the SoC has a high performance application processor capable of digital signal processing (DSP) and floating point, offering voltage and frequency scaling options. It runs up to 128MHz (514 CoreMark) with dedicated 1.0Mbyte flash and 512kbyte RAM, and a programmable, low power network processor running at 64MHz (244 CoreMark) with dedicated 256kbyte flash and 64kbyte RAM. The nRF5340 operates over a 1.7 to 5.5V supply voltage range and incorporates a new, power-optimized multi-protocol 2.4GHz radio with a TX current of 3.4mA (0dBm TX power, 3.0V, DC/DC) and RX current of 2.7mA (3.0V, DC/DC). Sleep current is down to 0.9 microA.
The Arm CryptoCell-312 hardware accelerates the ciphers and encryption standards required in the most security-conscious IoT products, says Nordic. Secure key storage is enabled by the key management unit peripheral, where the keys are physically isolated from processor access, and only the Arm CryptoCell-312 can access the secure keys. The secure bootloader in the nRF Connect SDK establishes a root of trust and extends this to a chain of trust by only booting software that has a verified signature. The bootloader also verifies that all incoming device firmware updates originate from an authenticated source.
The radio is capable of all Bluetooth direction finding features. The interface peripherals include NFC, USB, QSPI, and high speed SPI. The QSPI peripheral is augmented to interface with external memory at 96MHz. The nRF5340 is designed for extended operating temperature up to 105 degrees C.
The nRF Connect SDK, which supports Nordic’s nRF52 and nRF91 Series in addition to the nRF5340, offers a complete solution that integrates the Zephyr RTOS, protocol stacks, application examples, and hardware drivers.