Wireless SoC targets smart cities

Silicon Labs has announced the general availability of its flagship FG25 sub-GHz wireless SoC for long-range, low-power transmissions, initially introduced at the Silicon Labs Works With 2022 Developer Conference. The low-power wireless SoC features a high-performance 32-bit 97.5-MHz ARM Cortex-M33 with DSP instruction and floating-point unit for efficient signal processing, up to 1920 kB flash program memory and 512 kB RAM data memory, sub-GHz radio operation and transmission power up to +16 dBm.

FG25 wireless SoC block diagram. Click for a larger image. (Source: Silicon Labs)

Smart cities depend on moving beyond legacy solutions and adopting IoT capable of interoperability based on industry standards. It also means working in an expanded range, offering low power consumption and providing protection from existing and future threats, while minimizing the challenges of data loss.

Aimed at long-range, sub-GHz wireless connectivity for smart cities, smart metering, lighting and building automation, Silicon Labs claims the combination of the FG25 and the EFF01 RF power amplifier delivers the world’s most secure smart-city solution with the most internal memory in the company’s portfolio. The EFF01 RF front-end module amplifies the power and transmission range of the FG25 SoC, doubling its effective range. The FG25/EFF01 combo broadcasts up to 3 km with minimal data loss in urban environments.

Applications include connecting streetlights, cameras, weather stations, smart metering, utility transmission systems, city and building automation and enabling data sharing and optimization between city services to improve their efficiency, save costs and extract greater value from municipal services. OFDM, FSK, and OPSK modulation schemes allow for data rates up to 3.6 Mbits/s while keeping immunity to 2.4-GHz interference.

When combined with Secure Vault it reduces the risk of IoT ecosystem security breaches and the compromise of IP or revenue loss from counterfeiting, said Silicon Labs.

The FG25 is certified by the Wi-SUN Alliance for the PHY layer of the Field Area Network (FAN) 1.1 and is the first Silicon Labs SoC to support OFDM modulations introduced in the Wi-SUN FAN 1.1. It is built to perform as the flagship SoC for low-power wide-area networks (LPWAN) like Wi-SUN and other proprietary sub-GHz protocols.

One company that has benefited from the adoption of the FG25 Wi-SUN SoC is Landis+Gyr, a provider of energy management solutions. By adopting the FG25 Wi-SUN SoC, the company moved from a proprietary mesh protocol stack to a Wi-SUN standards-based stack, which increased the performance of its communications module and provided a smooth Wi-SUN transition as the FG25 also runs their proprietary stack.

It also increased interoperability and simplified development, particularly important for utility companies. The solution is based on implementing the Silicon Labs’ FG25, which met the criteria for developing a smart city networking solution that could keep pace with the latest Wi-SUN specification features to deliver high-throughput, reliable and secure products to consumers. The integration of an MCU and transceiver meant that Landis+Gyr has a single-chip design that leverages Wi-SUN features and is backward-compatible for its proprietary customers, even those that had not yet updated their infrastructure.

The FG25 and EFF01 are now available from Silicon Labs and its distribution partners. The FG25 is housed in a QFN56 7 × 7 × 0.85-mm package.