INSTRUMENTATION • ELECTRONICS
MAKING SENSORS SMARTER
Bianca Aichinger reveals how to efficiently power sensors used within the Internet of Things
W
ithout sensors, there would be no Internet of Things (IoT). They measure and record temperature, brightness, movement and many other parameters and transfer the
data to smart control devices. Sensors, however, need power. Although their power consumption is generally very low, they cannot work without it. Here, we describe how the service life of batteries can be extended. With the arrival of Industry 4.0, cyber-physical
systems, the IoT and cloud computing have found their way into modern factories. Operating as integrated communication networks, cyber-physical systems take decisions and act, while communicating in real-time with other systems as well as with humans. This development has made it possible to integrate more and more devices into networks where they combine, process and exchange ever-larger volumes of data. However, every single sensor in such a network must be supplied with power – be it through a central power supply, battery or energy- harvesting devices. Many IoT and Industry 4.0 applications run with 3V
coin batteries, which are not only cheap but also very reliable. However, such batteries need to be changed quite frequently. A fully charged CR2032 coin battery supplies approximately 3.2V. After only a few operating hours, the voltage drops however to below 3V, which might not be sufficient for certain wireless modules (WLAN, Bluetooth, LoRaWAN, etc.). As a result,
transmission can become unreliable or the signalling range might suddenly be limited.
USING SWITCHING REGULATORS The R-78S boost-switching regulator from Recom has been specially developed for battery-powered IoT devices. The plug & play module provides a stable output of 3.3V from input voltages of as little as 0.65VDC to 3.15VDC, squeezing the last bit of energy from the battery cell. The R-78S thus enables users to run microprocessors, WLAN/Bluetooth modules and IoT systems with a single 1.5V battery or cell, which has a much longer service life than a conventional coin battery. The figure below left, shows a
typical application of the R-78S in a wireless module. The circuit is only activated for brief periods to send data. During these short times, the entire circuit consumes around 600µW. When not sending data, the circuit is in sleep mode. During these times, the R-78S is powered by a buffer capacitor and consumes only 7µA. If the capacitor charge drops below a certain limit, the circuit is briefly activated for recharging. This technology guarantees reliable, maintenance-free operation for 10 years and more. Turning away from wires and batteries, sensors in
The R-78S boost-switching regulator prolongs the service life of batteries in IoT applications and also squeezes the last bit of power out of the cells
condition-based maintenance applications could be supplied by micro generators (MEMS), which harvest energy of up to 4mA through environmental conditions, such as vibrations, heat, light or temperature differences. An R-78S is ideal to support the MEMS in providing a stable output voltage to the sensor application. The IoT depends on innovative power supply solutions.
Recom offers intelligent components that help save battery power with the R-78S. These regulators squeeze the last bit of energy out of the battery, so that applications can run for more than a decade without problems. l
By integrating a buffer capacitor into the circuit, the R-78S can be set to sleep mode, saving valuable battery power
18
www.engineerlive.com
Bianca Aichinger is with Recom Power.
www.recom-power.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52
