June 2011, Sensirion AG, 8712 Staefa, Switzerland
Following the successful launch of the world’s smallest digital humidity and temperature sensor in 2010, the fully calibrated sensors of the SHT2x family have already won design slots in many applications. Now Sensirion has again significantly improved the temperature specifications of the standard SHT21 version. The temperature range for the tightest typical accuracy of ±0.3°C, originally specified as25 to 42°C, has been enlarged to the range of 5 to 60°C. In addition, accuracy at the limits of the measuring range has been distinctly improved.
This enables customers to benefit from significant product improvements with unchanged pricing. Along with outstanding long-term stability and low power consumption, very high precision can now be achieved over a temperature range that is significant for many applications. According to product manager Vincent Hess, “this makes the SHT21 specifically suitable for applications with very stringent temperature accuracy requirements.”
SHT21 consists of a newly designed, sophisticated sensor chip encapsulated in a DFN 3-0 package. With this encapsulation the chip is completely over-molded, except the humidity sensing area. In this way, the components size is reduced to a 3x3-mm footprint with 1.1-mm height. Additionally, over-molding provides excellent protection against aging and ambient impact, such as condensation and harsh environments, and thus yields outstanding long-term stability.
The SHT21 is fully calibrated and provides an I2C digital interface. Analog output modes (such as PWM) are available on request. The digital communication mode enables superb low power consumption: A value in the range of 3μW at normal operation is well achieved. Provided on tape & reel, the reflow solderable SHT21 is suitable for high volume applications. Furthermore, the sensor is qualified in accordance with automotive standard AEC-Q100 and an extended quality assurance program guarantees low PPM values.
SHT21 website: www.sensirion.com/en/sht21
SHT21 datasheet: www.sensirion.com/file/datasheet_sht21
The Swiss sensor manufacturer Sensirion AG is a leading international supplier of CMOS-based sensor components and systems. Its range of high-quality products includes humidity and temperature sensors, mass flow meters and controllers, gas and liquid flow sensors, and differential pressure sensors. Sensirion supports its international OEM customers with tailor-made sensor system solutions for a wide variety of applications. Among others, they include analytical instruments, consumer goods, and applications in the medical technology, automotive and HVAC sectors. Sensirion products are distinguished by their use of patented CMOSens® technology. This enables customers to benefit from intelligent system integration, including calibration and digital interfaces. Sensirion’s competence as a reliable OEM partner is underlined by its quality management system, which was certified in March 2008 in accordance with the ISO/TS 16949 standard.