P-NUCLEO-IKA02A1: A CO Detector Development Board So Flexible It’s Practically Doing Yoga

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The P-NUCLEO-IKA02A1 is a development board enabling engineers to quickly design a smart carbon monoxide (CO) detector using ST’s platforms and components. Smoke and gas detectors are great symbols of the smart revolution. We think so little of the original devices, found in homes and offices for ages, it takes a while to realize they are beeping because their batteries are dying. However, with the advent of connected home appliances, the carbon monoxide alarm market is set to grow at a compound annual growth rate of 10.16 % from 2017 to 2021, according to a recent study published by Research and Markets. After all, it’s easy to crave for the newfound peace that comes from knowing that the smallest fire or incident will immediately trigger a notification on our smartphones.

ST is in a unique position because it already manufactures a lot of the building blocks required to make a smart CO detector. Hence, the P-NUCLEO-IKA02A1 is a concentrate of technology, expertise, and experience at the disposal of engineers and enthusiasts. The retail kit ships with an NUCLEO-L053R8 that will serve as the base for the detector board. Hence, designers can immediately start developing their application on an STM32 microcontroller (MCU) their preferred toolchain. Finally, ST includes a CO collection tool that works with a basic lighter in order to test the detector’s responses. To know more about the P-NUCLEO-IKA02A1, we sat down with Jiri Hladik, Application Engineer at ST, who walked us through all the features that make it a unique development tool.

Two TSU111 at the Heart of the P-NUCLEO-IKA02A1

The P-NUCLEO-IKA02A1 (on top) and NUCLEO-L053R8 boards (at the bottom), and the CO Collection on tool (on the side) (click to enlarge)

The most fundamental constraint of a gas detector is the electrical properties of its sensor, which produces an extremely small current. For instance, a typical CO sensor will generate only one nano-ampere for every part per million (ppm) of CO concentration. As a result, engineers must find a way to amplify that signal before it is sent to the MCU, but the system must not introduce noise or an accurate measurement of the environment is impossible. This is why the P-NUCLEO-IKA02A1 uses two TSU111, the most precise nano operational amplifier given its power consumption.

The TSU111’s very low offset voltage of only 150 µV means this op-amp is extremely precise. At the same time, its sub-micro input current offers an amazingly low power consumption that ensures the CO detector works great with a coin-type battery. Hence, the unique properties of the TSU111 are behind the P-NUCLEO-IKA02A1’s success, but they also make the lives of engineers easier, because their design will be able to use the same op-amp. As a matter of fact, ST is already working on a solution that would combine two TSU111 under one package (TSU112), instead of the single op-amp solution today. This new device is currently planned for the end of 2017, and it would help simplify the final design inspired by the ST board.

The Most Amazing Removable CO Detector

The P-NUCLEO-IKA02A1 with the CO Detector TGS5141 from Figaro (click to enlarge)

The P-NUCLEO-IKA02A1 also ships with the TGS5141 from Figaro, which is one of the smallest CO detectors on the market today. One of its key features is that it integrates an electrolyte, instead of relying on a water reservoir, which tends to greatly increase the dimensions. The sensor works like a fuel cell, meaning that as carbon monoxide enters the component through a membrane, the oxygen reacts with the electrolyte, which causes electrons to move from one of the electrodes to another, generating a current, which the op-amp will amplify.

ST also understands that engineers need flexibility and pragmatism. Hence, a hidden feature of the P-NUCLEO-IKA02A1 is the possibility of using other gas sensors. Engineers can just remove the TGS5141 and replace it with a CO detector of their own choosing, or use a completely different sensor to detect carbon dioxide, dihydrogen, or sulfur dioxide, among many other gases. The rings and pre-drilled holes will guide them, making the P-NUCLEO-IKA02A1 one of the most versatile development platforms for smart gas detectors today. In other words, it is so flexible it just bends to the designers’ will.

Optimal Fusion of Hardware and Software

ST’s comprehensive approach to development board also means that the P-NUCLEO-IKA02A1 can be stacked with a module containing a sub-gigahertz transceiver, like the low-power S2-LP, to quickly start working on the wireless communication of the smart device. It’s as simple as adding another development board to the stack or starting with a tutorial on how to setup a 6LoWPAN network for these types of applications.

However, a hardware solution is nothing without efficient software tools to take advantage of it. This is why ST not only provides great development boards, but the company also offers Unicleo, a Graphical User Interface to represent the values from the gas detector in a graph that’s accompanied by the major surrounding data. This tool not only hastens development times by accelerating prototyping, it helps write the application’s code by centralizing the most important data to process. Furthermore, the NUCLEO-L053R8 comes pre-flashed so everything will work right out of the box, and ST provides application examples and source codes.

The P-NUCLEO-IKA02A1 kit is now available from major resellers for US$40 MSRP.