Wireless Temperature Sensor with Solar Battery Life Extender Eval Kit

July 17, 2018 by Paul Shepard

The DC2126A from Analog Devices (ADI) is a high-accuracy wireless temperature sensor, powered from ambient light, built using ADI integrated circuits. A 24-bit delta-sigma ADC reads a thermistor biased from a precision voltage reference. A switching power supply harvests energy from the built-in solar panel, and automatically switches over to the internal battery when no ambient light is available.

The DC2126A acts as a wireless node, or mote, in a SmartMesh IP network. Temperature readings are sent through the mesh network to a demonstration PC software GUI that displays temperature, and whether the DC2126A is running on solar power or on battery.

At the core of the DC2126A is the LTP5901-IPM, SmartMesh IP wireless mote (node), which provides the ultra-low power wireless mesh connectivity with >99.999% data reliability and communicates the temperature to a central access point (manager).

The LTP5901-IPM has on board an ARM Cortex-M3 processor, which can be loaded with user-developed application code using the SmartMesh IP On-Chip Software Development Kit (On-Chip SDK). In the DC2126A, custom application code controls the duty cycling of the voltage reference, samples readings from the ADC and sends the data packet through the SmartMesh IP network.

The DC2126A can be easily added to the DC9000B SmartMesh IP Starter Kit, or any SmartMesh IP network. The DC9000B SmartMesh IP™ Starter Kit provides all the tools for evaluating SmartMesh® network performance with respect to your application needs, including high reliability, ultralow power, scalability and ease of installation. This accelerates device integration and application software development.

DC2126A block diagram

The DC9000B Starter Kit includes five motes, or nodes (DC9003A-B), to enable you to quickly deploy a multi-hop mesh network in the RF environment specific to your application. The StarGazer evaluation software graphical user interface (GUI) allows you to quickly see the mesh network form, as well as key performance statistics, such as data reliability and latency.

The DC9003A-B Evaluation/Development Mote Modules feature easy-to-probe signal pins. In addition, the starter kit provides access to both manager and mote software application programming interfaces (APIs) over USB to enable application software development.

The DC2274A USB Network Manager comes factory-configured as an embedded network manager, where both the wireless-to-wired access point function and the network management algorithms run on board. Optionally, users may configure the DC2274 as a SmartMesh IP Access Point Mote for operation with VManager software. (Click here to learn more about network managers.)

The DC9000B Starter Kit operates in the 2.4000GHz to 2.4835GHz international license-free frequency band. Starter kits and demo boards are for evaluation purposes only. It remains the customer's responsibility to verify proper and reliable operation in the actual end application.