±2% accuracy in a whole range of relative humidity measurement – that´s just one of several improvements brought by the third generation of miniature calibrated sensors from company Sensirion.
Even the actual series like SHT1x and SHT2x belong to a top in this segment. Forthcoming series SHT3x (SHT30, SHT31 and soon also SHT35) addresses mainly those of you, requiring maximum accuracy even in limit values (humidity below 10% and above 90%), miniature dimensions and ultra low power consumption. So a main difference of a new SHT31 compared to SHT21 is, that a typical +-2% is maintained in a whole range. Together with a precise temperature measurement in element we still have a possibility to simply compute a dew point, what´s one of the key parameters for ventilation control (HVAC, heat recovery). If it´s “only” necessary to guide a humidity not to exceed certain level, then you´ll probably also use the output „Alert“ pin, able to start interrupt in a host MCU for instance or directly control further devices. Output of the SHT3x sensor is the linearized value, which can be easily transformed to a final value (%RH, °C).SHT31 is available in 2 versions – SHT31-DIS-B with a digital output via well-proven I2C bus (2 selectable addresses) and also in a version SHT31-ARP-B with a linearized analogue (proportional) output. That´s why SHT31-ARP-B is an interesting alternative for direct processing in analogue circuits, as it contains 2 independent outputs with output voltage of 10-90% Vdd, responding to 0-100%RH and -45 to +130°C temperature. Digital output version also features wide possibilities of setting regarding measurement frequency, communication speed and other parameters.
Even the humidity & temperature sensors can be “3G” – [Link]
With Sensirion humidity and temperature sensors you can be sure of what you measure. Moreover, now we´ll support your development by free samples.
Top-class calibrated humidity and temperature sensors Sensirion already gained many fans. Mainly thanks to a fact, that they´re not only “sensors” but a ready-made solution with a pre-amplifier, ADC and other circuits, which directly provide a final value in a digital form. That´s why it´s not necessary to solve input portion (noise, shielding, power supply, length of wires,…). Moreover, their long-term stability is verified in a praxis.
Features and usage of Sensirion sensors was introduced to you in many our articles. In the Sensirion portfolio can be found easily solderable types on a small PCB like for example SHT11(15) or SHT71 (75), as well as miniature types in SMT DFN packages like for example SHT21 (25) and also the new SHTC1. Small DFN package is practically impossible to solder manually, but it´s relatively easily manageable by means of a solder paste and a hot-air soldering station or ideally by a reflow in a hot-air oven.
Maybe, you´ve already noticed, that in many articles we also bring you a contest with a possibility to win free samples of a given component. We usually draw by lots 1-10 winners, which will directly receive free samples.
Still, if you´re seriously interested to try a given sample for a development of your (industrial) application, please contact us by e-mail. In many cases, we can provide you a given sample even if you wasn´t one of lucky winners of the contest.
Evaluate the Swiss precision for free! – [Link]
At the 2015 Mobile World Congress in Barcelona, Spain, the leading sensor manufacturer Sensirion will present a new multi-pixel gas sensor, plus a new barometric pressure sensor. Both new sensors, which rank among the smallest yet most accurate in their class worldwide, are capable of measuring indoor air quality (IAQ), the gases in a person’s breath, and barometric air pressure, as required for indoor navigation applications. The new sensors complement Sensirion’s existing product offering for wearables, smartphones, tablets, and the Internet of Things (IoT), and confirm the company’s status as the only sensor manufacturer to offer a complete solution all the way from sensor to cloud. With its trusted humidity and temperature sensors already established on the market, Sensirion is now expanding its range of environmental sensors to include gas and pressure sensors.
Sensirion presents the smallest and most accurate Gas and Pressure Sensors – [Link]
Miniature calibrated humidity and temperature sensor Sensirion SHTC1 is usable even in space – limited applications.
Really miniature dimensions and a low price are main benefits of new calibrated sensors SHTC1 from production of company Sensirion. If you ever tried well known sensors series SHT2x, probably you´ve been surprised by their small dimensions (3,2×3,2x2mm). However the new sensor SHTC1 shifts dimensions a level further, or better said – lower. The result is a DFN package with dimensions of only 2x2x0.75mm, what in praxis represents a package, which you may not notice at a cursory look at a populated PCB. That´s why the SHTC1 is primarily intended for mobile applications and everywhere, where a spared space and a minimal power consumption are beneficial.
Taking a low price in mind, the guaranteed accuracy of SHTC1 chip is relatively excellent, roughly on a level of SHT21. Typical accuracy of ±3% in a range of 20-80% RH and ±0.3°C is probably fully sufficient for majority of applications. 1.8 V supply voltage and ultra low power consumption below 1uJ/measurement are ideal for battery powered devices. SHTC1 supports I2C fast mode (0-400 kHz). This small package practically can´t be soldered by hand, but it is relatively easily possible by means of a solder paste and a hot-air soldering station.
Also the SHTC1 is produced by a well proven CMOSens technology, which proves its reliability and a long-term stability in industry. Similarly, the SHTC1 also isn´t only a “sensor” but a ready-made calibrated solution containing 2x sensor, low-noise amplifier, A/D interface, data processing unit with calibration data in a ROM and a communication interface. Detailed information can be found in the Sensirion SHTC1 datasheet and the Sensirion Humidity flyer.
We´ve got samples ready for you!
If you´re interested in trying this perspective sensor, take part in a contest below the article, or contact us on a well known address firstname.lastname@example.org.
SHTC1 we keep so far as an item upon order, but we´re able to supply it to you in a short leadtime and soon it will be a standard stock item.
SHTC1 – humidity and temperature from a pin head – [Link]
Complete digital temperature sensor Sensirion STS21 provides a top-level accuracy and stability for a very affordable price.
Digital sensor STS21 s the newest member of calibrated humidity and temperature sensors family SHT2x (SHT21, SHT25). In opposite to them, STS21 is able to measure only temperature, i.e. it´s suitable only for applications, where we don´t need to measure humidity. However a smaller functionality has also a significant positive aspect in a form of a substantially lower price. STS21 contains on a chip, similarly like its familiar, a temperature sensor, precise supply, low noise linear amplifier, AD converter and a serial interface with I2C output (fixed address different from SHT series).
Basic accuracy of STS21 in the 0 to +60°C temperature range is +-0.2°C. The user can choose a resolution for measuring and it can be 11-14 bits (up to 0,01°C). Despite the fact, that the sensor hasn´t guaranteed absolute accuracy of 0.01°C, such a high resolution can be beneficial for example for monitoring of a tendency (increasing/ decreasing) of temperature.
Detailed information can be found in the Sensirion STS21 datasheet.
STS21 measures temperature with an 0.01 °C resolution – [Link]
Kerry Wong writes:
In this post, I will show you yet another thermometer/hygrometer build. But instead of using an LCD or 7 segment display for the output, I decided to go retro, using two “needles” to display the temperature and humidity readings instead. And to make the project more fun, I did not use analog meters for the output but chose to use two servos instead. The temperature humidity sensor I used is SHT21 from Sensirion, the same sensor I used in my temperature logging project before. In that project, the temperature and humidity readings were sent over the network and displayed on my web server (you can see the current readings in my lab here).
A digital thermometer hygrometer with analog displays – [Link]
Calibrated differential pressure sensors will find usage in industry and also in every smart home.
Ventilation, air conditioning (HVAC), or any other applications, where a pressure or a flow of air (gas) is essential, can be precisely regulated only if we know a real pressure/ flow conditions. Monitoring of fans functionality, status of filters, …, even for this purpose are very suitable differential pressure sensors from Swiss company Sensirion with an excellent accuracy and long-term stability.
As SDP sensors are differential, they have 2 nozzles. The base of these sensors is a miniature heating element and two temperature sensors. Difference of pressures will cause a small air flow through a component and it will cause a temperature difference in these built-in sensors. Temperature difference is directly depending on the amount (weight) of air flowing through a sensor and it naturally depends just on a pressure difference. A great advantage against membrane pressure sensors is a long-term high accuracy even at measuring of small pressure and maintaining of accuracy of a “zero point”.
As an air specific weight depends on temperature, measurement based only on a temperature difference of two internal sensors wouldn´t be accurate. That´s why SDP sensors have a built-in temperature compensation and linearization, thus an output of a sensor is directly a value usable for further processing. Resolution of sensors is very high and is user selectable in a range of 9-16 bits. Resulting binary value read-out through I2C interface can be divided by a constant shown in a tab. 2.1 on page 3 of the SDP6xxv1.7 datasheet and we´ll get a resulting value in desired units (Pa, bar, inch).
Universal and price-attractive series is the SDP600 (6xx) series, in which we´ll find types optimized for measurement of pressure (SDP 600/610), mass flow (SDP601/611) and types with a minimal power consumption suitable even for battery-operated devices (SDP606/616). All these types are able to measure “bidirectionally” i.e. positive and even negative values. For applications, where we know, that a pressure difference will be always positive (flow by only one direction), it´s possible to use more price-affordable types SDP 500/510 (in fact even these types measure bidirectionally, but their accuracy is not guaranteed in this range). For the most of applications no additional compensation is necessary, only it can be necessary to multiply a resulting value by a constant for an altitude compensation shown in a table 5.4 on page 6 in the datasheet.
How can be this small sensor used to measure flow of a big amount of air?
Relatively simply. All that is necessary is to make a small orifice in a pipe and this way to create a “resistance” as described in the SDPxxx_Bypass_Configuration application note. In an electronics analogy the differential pressure measurement is similar to measurement of voltage on a resistor, which depends on a current flowing through a resistor. SDP sensors can be used even for measurement of a pressure difference in a given pipe against a surrounding environment, in such a way, that one nozzle of sensor will be left “unconnected”. Naturally, such a configuration can only be used if a small leakage of a measured “gas” (air) is acceptable.
Sensirion SDP sensors measure pressure but even a flow – [Link]
Humidity can be measured by various sensors, but sensors SHT from company Sensirion add many benefits moreover.
To be exact, a word „sensors“ is not a suitable expression in this case. As SHT series sensors contain on one chip humidity and temperature sensor, precise supply, low noise linear amplifier, AD converter and a serial interface, they represent a ready-made “device”. Moreover, they´re calibrated, thus to get an exact value it´s only necessary to read out data through a serial interface. In case of SHT2x series, it´s a standard, easy-to-implement I2C interface.
Sensirion sensors SHT2x series was more in detail introduced to you in our article „New sensors Sensirion will take you only 3x3mm on PCB!”, that´s why we´d like to bring you mainly few tips for simplification of development now.
Area of relative humidity and physics of water vapors is quite ample and into its introduction will initiate you the document Introduction_to_Relative_Humidity. Don´t be scared of many quotations, which you´ll find there – fortunately in common praxis we usually manage it with values of relative humidity and a dew point, which can be found together with code examples in Humidity_at_a_Glance.
As humidity sensors are very often used in residential places for regulation of heating and ventilation, also useful can be information about influence of humidity on a thermal comfort. For a practical usage of sensors it´s also important their placement on a PCB and a good access of air, what is in detail described in the document Sensirion_Humidity_Design_Guide. SHT2x are intended for 3VDC power supply, that´s why when using in 5V applications, you can face a problem of different voltage levels. This can be easily solved for example by a circuit described in the document SHT2x_5V_Supply_Embedding.
The program itself doesn´t need to be developed “from zero”. Examples can be found in the document SHT21_Sample_Code and SHT2x_Electronic_Identification_Code. Detailed information about testing and specification of SHT sensors can also be found in documents Sensirion_Humidity_Sensor_Specification_Statement and Sensirion_Humidity_Testing_Guide.
SHT25 – humidity and temperature precisely in every season – [Link]
Temperature, pressure, humidity, flow – all this you have under control with the Sensirion components, the top quality Swiss producer.
CMOSens technology and other innovative technologies of company Sensirion enabled production of top quality calibrated sensors with a long lifetime. As you may have read in our articles:
- New sensors Sensirion will take you only 3x3mm on PCB!
- Professional humidity and temperature measuring with calibrated sensors Sensirion
- Professional solution for accurate measurement of humidity and temperature
or other. Sensirion sensors in fact aren´t sensors but ready-made solutions with a sensor, preamplifier, AD converter and a communication interface. The result of this concept is high disturbances immunity, high accuracy, saving of components and a simplified development.
Do you develop an application, where you´d use Sensirion components?
As we are an authorized Sensirion distributor, we´re able to provide you with free samples of many Sensirion components, especially RH&T and pressure sensors.
Describe us your industrial project in which you´d like to use a given component and let us know at email@example.com.
Soselectronic supports your development with free samples of Sensirion sensors! – [Link]
The world’s smallest humidity and temperature sensor was introduced at Electronica 2012 by Sensirion, setting new standards for size and power consumption.
The SHTC1 sensor is designed for mobile deices, measuring 2 x 2 x 0.8 mm. Based on the company’s CMOSens Technology, the sensor and signal processing electronics are combined on a single silicon chip.
The devices measure relative humidity over a range of 0 to 100 %RH with a typical accuracy of ±3 %RH. The temperature measuring range is -30 to +100 °C with a typical accuracy of ±0.3 °C. Fully calibrated, the sensor has a digital I²C interface, and is suitable for reflow soldering. This makes it compatible with standard industrial mass production processes for electronic modules. Contact company for pricing and availability.
World’s smallest humidity and temperature sensor – [Link]