Dual-band SoC targets long-range networks

Silicon Labs has introduced its new FG28 dual-band SoC, designed for long-range networks and protocols like Amazon Sidewalk, Wi-SUN, and other proprietary protocols. The wireless SoC includes radios for sub-GHz and 2.4-GHz Bluetooth LE, a built-in AI/ML accelerator for machine learning inference and the company’s Secure Vault technology.

The new FG28 dual-band SoC from Silicon Labs supports sub-GHz wireless protocols and Bluetooth LE. (Source: Silicon Labs)

Silicon Labs said the new SoC addresses a variety of key requirements for developing and deploying low-power wide area networks. For example, Bluetooth enables easy deployment of new devices on the network while sub-GHz supports device communications over one mile for new edge applications, such as neighborhood networks like Amazone Sidewalk, smart cities or smart agriculture.

The benefit of the dual-band capabilities is that the chip supports multiple protocols in a single design. As noted above, Bluetooth enables easier device deployment, but it also allows operators to connect to the device locally for functions like diagnostics and data downloads. The sub-GHz connectivity, using networks like Wi-SUN, allows the FG28 to be used as the battery-operated end node in smart cities for applications such as livestock trackers and health monitors, said the company.

Key features include a 32-bit 78-MHz ARM Cortex-M33 with DSP instruction and floating-point unit, an integrated AI/ML hardware accelerator and 1024 kB of flash storage and 256 kB of RAM to meet a range of protocols and technology stacks.

Silicon Labs claims the FG28 is the industry’s first integrated AI/ML accelerator in a sub-GHz SoC. This enables machine learning inference at the edge for a range of applications, including predictive maintenance warnings and monitoring soil conditions, said the company.

The low-power wireless SoC delivers sub-GHz radio operation with TX power up to +20 dB and 2.4-GHz BLE radio operation with TX power up to +10 dBm. Other key specs include a wide operating range from 1.71 V to 3.8 V and a wide operating temperature range of -40 °C to 125°C. The device also offers a variety of MCU peripherals, including analog-to-digital converters, digital-to-analog converters, analog comparators, time counter, DMA controller, watchdog timer and up to 49 GPIOs.

FG28 dual-band SoC block diagram (Source: Silicon Labs)

The SoC’s integrated Secure Vault suite of security features allows designers to choose the level of security they need for the applications. The technology protects against scalable local and remote software attacks as well as local hardware attacks. Key features include Arm TrustZone, secure key management, secure boot, anti-rollback prevention, anti-tamper, secure attestation, differential power analysis countermeasures, secure debug, secure link and true random number generator.

The FG28 is sampling now with general availability planned before the end of the third quarter of 2023. The FG28 also will be available in variants optimized for Amazon Sidewalk and Z-Wave Long-Range as well as a standalone MCU.

Silicon Labs offers an on-demand replay of its Tech Talk, “Designing Long Range Devices with Amazon Sidewalk,” for designers interested in developing for Amazon Sidewalk using Silicon Labs’ SoCs.

Earlier this year, Silicon Labs announced the general availability of its flagship FG25 sub-GHz wireless SoC for long-range, low-power wide-area networks (LPWAN) like Wi-SUN and other proprietary sub-GHz protocols.