Mesh network-optimized module enables large-scale IoT deployments


Würth Elektronik’s Thetis-I module uses Nordic nRF52840 SoC-enabled Wirepas software to support IoT mesh configurations

Nordic Semiconductor today announces that Würth Elektronik, a Waldenburg, Germany-based developer of electronic and electromechanical components, has selected Nordic’s nRF52840 Bluetooth® 5.2/Bluetooth Low Energy (Bluetooth LE) advanced multiprotocol System-on-Chip (SoC) to power its ‘Thetis-I’ module for Internet of Things (IoT) device manufacturers across supply chain, asset tracking, smart lighting, and smart metering applications.  

Thetis-I is supplied pre-installed with ‘Wirepas Massive’ (previously Wirepas Mesh), a decentralized mesh networking solution, ensuring the module is optimized for large-scale IoT networks. Wirepas Massive has been developed by the global software connectivity company, Wirepas, and is designed for a wide array of ‘massive IoT’ applications. The agreement between Würth Elektronik and Wirepas means companies designing-in the Thetis-I module can go into production without having a Wirepas Software License Agreement as this is covered by Würth. 

Large scale mesh-enabled 

Thetis-I can be integrated into any embedded application to enable Wirepas Massive mesh networking capabilities. The powerful, pre-certified ready-to-use firmware enables robust and secure data transmissions in mesh configurations between Thetis-I modules and/or to other Wirepas Massive-enabled sensor devices in the network. Any device using the module can be authenticated in a secure manner while joining the targeted network. The module supports either stand-alone (single MCU) operation—where a Thetis-I-module integrates the Wirepas Massive firmware and the custom developed application as an individualized product—or host-controlled (dual MCU) operation, where the application runs on an external microcontroller and Thetis-I is used as an off-the-shelf product. Each device integrating a Thetis-I radio module can also perform as a low power router meaning no further infrastructure is required for mesh communication. Such a router can have a lower than 30µA power consumption while still keeping active bidirectional communication. 

We took advantage of Nordic’s very good technical knowledge especially in the 2.4GHz field
Luca Settembre, Würth Elektronik

Nordic’s nRF52840 is the company’s most advanced ultra low power nRF52 Series SoC. The nRF52840 is Bluetooth 5-, Thread 1.1-, and Zigbee PRO (R21) and Green Power proxy specification-certified and its Dynamic Multiprotocol feature uniquely supports concurrent wireless connectivity of the protocols. The SoC combines a 64MHz, 32-bit Arm® Cortex® M4 processor with floating point unit (FPU) with a 2.4GHz multiprotocol radio (supporting Bluetooth 5, ANT™, Thread, Zigbee, IEEE 802.15.4, and proprietary 2.4GHz RF protocol software) with 1MB Flash memory and 256kB RAM. The radio with on-chip PA provides features -95dBm RX sensitivity (at 1Mbps Bluetooth LE), a maximum output power of 8dBm, and a total link budget of 103dBm. 

Low current consumption

The Thetis-I module is supplied in an 8 by 12 by 2mm form factor and can be configured to use either the on-board PCB antenna (ensuring the module can be easily designed-in to compact end devices), or an external antenna of the developer’s choice—for high performance and extensive range. Using the nRF52840 SoC, the module also provides extremely low current consumption, making it suitable for battery driven applications.  

Würth Elektronik offers developers the ‘Thetis-I Evaluation Kit’ containing an evaluation board (which allows a controller board to be connected for developing applications), USB radio stick, and three battery-powered sensor boards with a pressure sensor and humidity sensor (both also integrating a temperature sensor) providing an application example for a Wirepas Massive network. The ready-to-use kit enables product evaluation and rapid prototyping of a Wirepas Massive network. The prototype network can be tested in the field under real environmental conditions. Both the Thetis-I module and Thetis-I Evaluation Kit can be configured remotely from a PC using the free-of-charge Wirepas Commander software. Wirepas technology enables easy connection to established Cloud platforms.  

“We selected Nordic’s nRF52840 SoC for our Thetis-I module because of the chip’s size, radio sensitivity and power consumption,” says Luca Settembre – Product Manager for GNSS and Wirepas products at Würth Elektronik.  

“In addition, we took advantage of Nordic’s very good technical knowledge especially in the 2.4GHz field, the company’s fast response times, single and dual MCU reference designs, and its Software Development Kit [SDK] which is one of the best on the market and allows easy firmware development.”  

“Würth Elektronik’s Thetis-I module has made it easier than ever for design partners to kick-start a development with Wirepas Massive,” says Thomas Weisshaupt, Head of D-A-CH for Wirepas.  

“Even if the business case of an IoT project often implies high density and large scale in one network you have to start with one device. Würth Elektronik offers a rapid prototyping opportunity. Nordic’s long term relationship with both Wirepas and Würth Elektronik now delivers a unique offer to the IoT community.”