Silicon Labs Rolls Dual-band SoC for Long-range Wireless Protocols

June 12, 2023 by Jake Hertz

A new SoC from Silicon Labs supports multiple protocols and is optimized for Amazon Sidewalk.

The Internet of Things (IoT) and the general emergence of connected devices have led to a significant increase in the importance of wireless hardware. In particular, to meet the varying needs of IoT devices, the demand for wireless hardware that can simultaneously support multiple wireless protocols has skyrocketed.

Last week, Silicon Labs answered this call with the release of a new dual-band wireless SoC that is meant specifically to support long-range wireless protocols and Amazon Sidewalk.


This dual-band FG28 SoC is designed for protocols like Amazon Sidewalk, Wi-SUN, and proprietary protocols.

This dual-band FG28 SoC is designed for protocols like Amazon Sidewalk, Wi-SUN, and proprietary protocols. Image used courtesy of Silicon Labs


In this article, we’ll talk about Amazon Sidewalk as well as Silicon Labs’ new wireless SoC offering.


Amazon Sidewalk

In the world of IoT and the smart home, one of the most exciting technologies to emerge in recent years is Amazon Sidewalk. As covered in previous All About Circuits articles, Amazon Sidewalk is a community-based network introduced by Amazon with the goal of expanding connectivity for low-bandwidth devices such as smart lights, sensors, and various Internet of Things (IoT) devices.

By leveraging Bluetooth Low Energy (BLE) and the 900 MHz LoRa spectrum, Sidewalk establishes a means for these devices to communicate not only with each other but also with Amazon's servers, even when they are beyond the range of a user's Wi-Fi network.


Amazon Sidewalk is a shared network. Image from Amazon


The fundamental idea behind Sidewalk involves the creation of a long-range network that operates on low bandwidth. While third-party IoT devices don't directly interact with one another, they can utilize Ring/Echo devices as bridges to transmit their communications. However, it's important to note that these Echo/Ring devices, acting as intermediaries, do not engage in direct communication with one another.

An intriguing aspect of Amazon Sidewalk is its shared nature. By choosing to participate, your Amazon devices can contribute to extending the network's coverage area, benefiting a larger community.

For instance, if your neighbor's Wi-Fi signal doesn't reach your backyard, but they possess Sidewalk-enabled devices, your own devices can connect to their network, and vice versa. This collaborative approach creates a network that fosters mutual advantages for all residents within the neighborhood.


Silicon Labs’ New SoC

Silicon Labs’s new SoC, called the EFR32FG28, is a dual-band, sub-GHz wireless + 2.4 GHz BLE SoC that offers a number of unique features for a wireless SoC. 

One notable feature of the new piece of hardware, according to the datasheet, is that it is a multiprotocol device designed to support long-range communication. With a low-power RF transceiver (as low as 33 µA/MHz in Active Mode at 39 MHz and 1.3 µA in DeepSleep) as well as integrated power amplifiers with up to 20 dBm output, the new device can support protocols such as Amazon Sidewalk, Wi-SUN, sub-GHz, and 2.4 GHz BLE.


EFR32FG28 block diagram.

EFR32FG28 block diagram. Image from Silicon Labs. (Click image to enlarge)


From a compute perspective, the device is built around a 32-bit, 78 MHz Arm Cortex-M33 core with up to 1024 kB of flash and up to 256 kB of RAM. More notably, Silicon Labs claims that this device is the industry’s first sub-GHz SoC to integrate an AI/ML hardware accelerator. The accelerator in question is specifically a matrix-vector processor and is said to allow for edge computing in IoT devices.

Additionally, the device features a number of key MCU peripherals including 16-bit and 32-bit timers/counters, watchdog timers, 2x analog comparators, 2x DACs, and an ADC.


A Swiss Army Knife

According to Silicon Labs, their intention with this product was to create a “swiss army knife” wireless SoC. Between dual-band support for a variety of wireless protocols, a versatile computing core with a slew of peripherals, and an integrated AI/ML accelerator, it certainly seems that the EFR32FG28 is a device that can serve the needs of many different designs and use cases.