High-accuracy humidity sensors extend system reliability

Texas Instruments (TI) has unveiled the first devices in a new family of humidity sensors that claim the industry’s highest reliability and accuracy and the lowest power consumption. With built-in protection of sensing elements, the HDC3020 and HDC3020-Q1 humidity sensors are designed to enable more reliable industrial and automotive systems that withstand potential damage caused by moisture and changing water vapor conditions over time.

Relative humidity (RH) sensors are used in applications where moisture can affect system performance and lifetimes, such as vehicles, appliances, and medical equipment.

The HDC3020 and HDC3020-Q1 sensors are said to offer improved relative humidity measurement accuracy with reduced long-term error, when compared to existing RH sensors. The devices “preserve data integrity under stress conditions and are the industry’s first to provide integrated correction to adapt to drift caused by natural aging, environmental stress or interactions with contaminants,” said TI.

(Image: Texas Instruments)

The humidity sensors also claim lower drift in extreme conditions than competing devices, with less than 0.21% RH accuracy drift per year and less than 5% RH drift from temperature and humidity stress (tested up to 85% RH and 85°C). As a result, this sustained accuracy is said to enable longer system lifetimes, eliminating the need to frequently replace or recalibrate the sensor.

The HDC3020 and HDC3020-Q1 devices tout the highest accuracy across the full supply voltage of 1.62 V to 5.5 V and the widest temperature and humidity range at ±1.5% RH. This enables more precise control of a system to help increase efficiency by ensuring the system only runs when necessary. TI said the accuracy is verified with a procedure traceable to the National Institute of Standards and Technology.

(Image: Texas Instruments)

Other features include ultra-low-power consumption (nanoampere) across a wide supply range from 1.62 V to 5.5 V that enables low-power operation while a system is actively running and in sleep mode and an automatic measurement mode that enables humidity sensing at regular intervals to capture data while the rest of the system sleeps. This feature is particularly beneficial in applications such as cold-chain data loggers, IP network cameras, or wirelessly connected environmental sensors such as air-quality monitors, smart home or wireless sensor nodes in buildings, according to TI.

The humidity sensors are available in several pin-to-pin compatible package cover options, such as removable polyimide tape and permanent IP67-rated filter covers. The covers provide ingress protection against dust and moisture during assembly and system lifetimes. Preproduction versions of the HDC3020 and HDC3020-Q1 are available exclusively on TI.com in 8-pin leadless plastic small-outline packages. Pricing starts at $1.65 in quantities of 1,000. Devices that offer analog output and packages with protective covers are expected to be available by the end of the year.