AHT21 Integrated Temperature And Humidity Sensor

AHT21 is equipped with a newly designed ASIC dedicated chip, an improved MEMS semiconductor capacitive humidity sensor element and a standard on-chip temperature sensor element. Its performance has been greatly improved or even exceeded the reliability level of the previous generation of sensors. A generation of temperature and humidity sensors have been improved to make their performance more stable in harsh environments.

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1. Product Overview

As a new generation of temperature and humidity sensors, AHT21 sets a new standard in terms of size and performance: a two-row flflat pin less SMD package suitable for reflflow soldering, bottom face 3x3mm, height 0.8mm. The sensor outputs calibrated digital signals in standard IIC format.

AHT21 has a new designed ASIC chip, an improved MEMS semiconductor capacitive humidity sensor and a standard temperature sensor. It has better performance and higher reliability compare with old generation sensors. It’s more stable even in harsh environment.

Each sensor is calibrated and tested, and the product lot number is printed on the surface of the product. Due to improvements and miniaturization of the sensor, it is more cost-effffective, and ultimately all devices will benefifit from cutting-edge energy-saving operation modes.

2.Application Range

HVAC, dehumidififier, testing and inspection equipment, consumer products, automobiles, automatic control, data loggers, weather stations, home appliances, humidity control, medical and other related temperature and humidity detection and control.

3.Product Characteristics

  • Fully calibrated
  • Digital output, I²C interface
  • Excellent long-term stability
  • Adopt SMD package suitable for reflow soldering
  • Quick response and strong anti-interference ability

4.Product Related Data Download

Additional information

Supply voltage

DC : 2.2 – 5.5V

Measuring range (humidity)

0 ~ 100% RH

Measuring range (temperature)

-40 ~ + 120 ℃

Humidity accuracy

± 2 % RH ( 25 ℃ )

Temperature accuracy

± 0.3 ℃

Output signal

I2C signal