Humidity is notoriously difficult to measure. Some of the scientific and electronic considerations to measuring humidity include: analog to digital interface and external circuitry which might require op-amps or oscillator circuitry; temperature compensation adjustments to calculate dew point; calibration against a known humidity source; mounting, protection and response time in the real-world. If you're interested in the details see Tracy Allen's web site (EME Systems) for his discussion.
The Sensirion SHT1x addresses many of these issues head on. It is a smart sensor for both humidity and temperature, and it comes from the factory in a tiny package that incorporates the analog to digital interface. All that your microcontroller has to do is read out the humidity and temperature values through the two-wire digital serial interface. The only math required is a simple scale and offset. The SHT1x is factory calibrated so that it returns temperature with a resolution of 0.01 degrees Celsius and relative humidity with a resolution of 0.03 percent. The accuracy is better than most other sensors too. Worst-case temperature accuracy is +/- 2 degrees C - but in the "room temperature" range the accuracy better than +/- 1 degree C. The relative humidity sensor is similarly accurate: +/- 3.5% in the range 20% to 80%. This is quite remarkable for a low-cost sensor. Excellent for commercial or home-based projects that require such readings.
- Provides a fully calibrated, digital output
- Measure temperature with a resolution of 0.01 degrees and within +/- 2 degree accuracy
- Measures relative humidity with a resolution of 0.03%and within +/- 3.5% accuracy
- Low power consumption (typically 30 μW)
- Power requirements: 2.4 to 5.5 VDC
- Communication: Two-Wire Serial
- Dimensions: 0.43 x 0.49 in (11 x 12.5 mm)
- Operating temp range: -40 to +254.9°F (-40 to +123.8°C)
Downloads & Resources:
Sensirion Kit Documentation (.pdf)
Sensirion SHT1x Documentation and Source Code (.zip)
Sensirion SHT1x Data Sheet (.pdf)
Javelin Stamp Example Code (.zip)
N&V column "Environmental Sensing" #91 (.pdf)
N&V code "Environmental Sensing" #91 (.zip)
Sensor Objects for Propeller Programmers
Dimensions (inc. headers):
- Length: 12.69mm/0.50in
- Width: 11.16mm/0.44in
- Height: 11.56mm/0.46in
- Weight: 1.03g/0.04oz
This product is listed in:
Documentation and Resources:
- Powerboost your LiPo Batteries
We're going to pick up where the LiPo Battery tutorial left off and look closer at the Adafruit Powerboost modules for charging your LiPos. We talked about the rules of using these batteries and how to make sure you don't set your project a light whe...
- The Maker Revolution
The Maker Revolution celebrates the creation of new devices and the modification of existing ones - the transition from a consumer buying goods to eventually having a major part in their creation. The Maker Revolution places strong emphasis on free (...
Exact shipping can be calculated on the view cart page (no login required).
We deliver Australia-wide with these options:
- $3 for Small Items (3-7 days, not tracked, only available on selected small items)
- $6.95 for Standard Post (2-4 days, tracked)
- $8.95 for Express Post (Overnight for Australia Post Next Day Network, tracked)
- Pickup - Free! Only available to customers who live in the Newcastle region (only after we email you to notify your order is ready)
International Orders - the following rates are for New Zealand and will vary for other countries:
- $11.49 for Pack and Track (3+ days, tracked)
- $16.50 for Express International (2-5 days, tracked)
If you order lots of gear, the postage amount might increment based on the weight of your order.
Our physical address (here's a PDF which includes other key business details):
Unit 18, 132 Garden Grove Parade
Take a look at our customer service page if you have other questions such as "do we do purchase orders" (yes!) or "are prices GST inclusive" (yes they are!). We're here to help - get in touch with us to talk shop.