SHT40I-HD1B Analog Humidity Sensor Sensirion SHT40I-HD1B Analog Humidity Sensor has been specifically developed for demanding industrial applications such as refrigerators, air conditioners, and any other application where high system noise prevents the use of digital solutions. The SHT40I-HD1B offers 5V supply voltage, robust housing, and increased ESD protection to match the requirements of harsh operating environments. An optional periodic variable power heater allows for operation in highly demanding environments, including those with constant high humidity and condensing atmospheres.