Digital temperature and humidity sensors are conducive to improving the adaptability of software and hardware. Ultra-high-precision, low-power TI temperature and humidity sensor. According to TI's official introduction, the sensor has ultra-high detection accuracy and reliability. In extreme cases, the accuracy drift is lower than that of similar devices, and it maintains long-term performance consistency.

A temperature and humidity sensor is a sensor that detects ambient temperature and humidity. With the rapid development of microprocessors, the combination of microprocessors and sensors has promoted the transformation of various industries to intelligence. ATMEGA88PA-MMHR temperature and humidity sensor also plays an important role in the wave of industrial reform, and is an important core component of the intelligentization of various industries.

For example, in smart home applications, the temperature and humidity sensor can collect the ambient temperature and humidity changes in the room in real time, convert the collected environmental information into electrical signals through the sensor's internal circuit, and transmit it to the smart home master control system, and then the master control The system determines whether dehumidification, humidification or temperature adjustment is required, so as to ensure the dry and wet balance in the room and improve the user's better living environment and quality of life.

In addition to smart homes, temperature and humidity sensors are also indispensable in applications such as industrial equipment, automobiles, household appliances, and medical equipment. Abnormal temperature and humidity in the working environment will seriously affect the stability and safety of the equipment, and even cause irreversible damage to the equipment and shorten the service life.

It is certain that various industries will develop in the direction of digitization, automation and high integration, so which direction will temperature and humidity sensors develop in the future?

The development trend of temperature and humidity sensor

High precision, digitization, and digital transformation are the general directions for the development of various industries, and natural sensors are no exception. Digital temperature and humidity sensors are conducive to improving the adaptability of software and hardware. Through the cooperation of software and hardware, it is beneficial to improve the acquisition accuracy and automation capability of the sensor, thereby improving the overall work efficiency of the device.

With the increase of the functions of the application equipment and the introduction of more components, the internal space of the equipment that was not rich is becoming more and more crowded, so it is a general trend for sensors to be miniaturized and highly integrated.

Low-power, passive is more than just a temperature and humidity sensor. Currently, many sensors are moving in a passive direction. As the application scenarios of various devices gradually expand to the outdoors, passive sensors are more conducive to improving the durability of the device and the service life of the battery.

Ultra-high-precision, low-power TI temperature and humidity sensor

Previously, TI officially released the HDC3020, which can withstand the impact of humid environments and meet ultra-high precision and low power consumption temperature and humidity for industrial and automotive applications. The sensor has a built-in anti-pollution protection mechanism that can respond to changing ambient humidity at any time, ensuring the reliability of equipment applications.

According to TI's official introduction, the sensor has ultra-high detection accuracy and reliability. In extreme cases, the accuracy drift is lower than that of similar devices, and it maintains long-term performance consistency. The annual relative humidity accuracy drift can be effectively controlled within 0.21%. Even if it works continuously for ten years, the detection error accuracy is only reduced by 4% at most, which is a lot lower than the 8% error of the same type of sensor. For equipment with a service life of more than 10 years, such as automobiles and industrial equipment, large measurement errors will reduce the operating efficiency and expected service life of the equipment to a certain extent.

Figure: Measurement accuracy varies with years of use

The above picture shows the HDC3020 temperature and humidity sensor and similar products. The relative humidity measurement accuracy drift curve changes with the working years. In contrast, the initial drift accuracy of the HDC3020 temperature and humidity sensor is lower than that of similar products, and the annual growth rate of the HDC3020 is also relatively low.

Such a small drift accuracy is mainly due to TI's integrated on-chip accuracy drift correction technology, which can effectively deal with the accuracy drift problem caused by various stresses such as natural aging of the sensor, environmental pressure or pollution. At the same time, it can also eliminate the small precision drift of the sensor in the initial stage, ensure the integrity of data preservation in various working environments, and improve the reliability of the sensor carrier operation.

In terms of product details, the sensor has two detection functions of humidity and temperature. The relative humidity measurement accuracy is 1.5%RH, the temperature measurement accuracy is 0.1℃, and the operating voltage is 1.62V to 5.5. The wide working voltage is beneficial to improve the application coverage of the sensor and meet the application requirements of different voltages. At the same time, HDC3020 can also guarantee the working stability in extreme temperature and humidity environments such as -40°C to 125°C and 10%RH to 90%RH, meeting the requirements of high temperature, high humidity or low temperature drying application scenarios such as automobiles and industrial equipment.

Sensirion Digital Temperature and Humidity Sensor

Last month, Sensirion officially launched the SHT4xi series of digital temperature and humidity sensors suitable for industrial applications, which is the fourth generation of Sensirion products, mainly composed of SHT40I and SHT41I.

This range of sensors utilizes proven CMOSEns technology and seamlessly integrated rugged housings. Ideal for measuring temperature and humidity under harsh conditions in industrial applications. At the same time, the variable power heating function is integrated on the sheet to ensure the normal operation of the equipment in extreme weather environments.

In order to improve the measurement accuracy of the sensor, Sensirion also added the I2C fast mode Plus interface to this series of sensors, which can calibrate the measurement accuracy of the sensor and improve the measurement accuracy, thereby ensuring long-term reliability and longer service life in the application carrier.

In terms of product details, the relative humidity measurement accuracy of this series of sensors is 5%RH, and the temperature measurement accuracy is 0.2°C, which is slightly lower than that of TIHDC3020. At the same time, this series of sensors can be used in working environments with relative humidity ranging from 0%RH to 100%RH and temperatures ranging from -40°C to 125°C. However, when the end of the SHT40I is dry or wet, the highest accuracy is 8%RH, and the accuracy is 1°C under extreme temperatures. The detection accuracy of the SHT41I is less affected by temperature and humidity.

Epilogue

When selecting a temperature and humidity sensor, not only the measurement accuracy of the sensor, but also the accuracy drift amplitude and environmental impact of the sensor during long-term use, and whether the sensor has an accuracy drift correction function. In the equipment with long service life such as the automobile industry equipment, the drift correction function is particularly important, which not only ensures the consistency of the long-term performance of the sensor, but also reduces the maintenance cost of the equipment to a certain extent and prolongs the service life.