SparkFun Formaldehyde Sensor - SFA40 (Qwiic)

The SparkFun SFA40 Qwiic Formaldehyde Sensor is a unique indoor gas sensor that measures low concentrations of formaldehyde (CH2O/HCHO) with excellent accuracy even in the presence of other similar gases. The SFA40 communicates over I2C so we put it on this Qwiic breakout to easily integrate it into a Qwiic circuit with no soldering necessary.High-Accuracy Environmental SensingThe SFA40 from Sensirion is an electrochemical sensor that maintains accurate formaldehyde measurements in environments that have other common indoor gases such as ethanol or nitrogen dioxide. This sensor also comes pre-calibrated with a unique manufacturer serial number for easy identification. To ensure your readings are as precise as possible the SFA40 provides several key performance benefits:Wide Measurement Range: Detects formaldehyde gas concentrations from 0 to 2000 parts per billion (ppb).High Accuracy: Delivers measurements within ±20 ppb or ±20% of the total measured value whichever is larger.Low Cross-Sensitivity: Highly resistant to interference with a cross-sensitivity to ethanol of just 0.3%.Environmental Compensation: An integrated temperature and humidity sensor automatically adjusts for changing ambient conditions.Operation and Qwiic IntegrationWhile the SFA40 requires a 10-minute initialization period before it measures gas concentrations within its stated specifications it responds to changes in under two minutes once properly warmed up. It also operates highly efficiently consuming an average of just 80µA at 3.3V. This low power draw makes it an excellent choice for continuous monitoring thanks in part to its operational lifetime of over six years.For hardware connections dual Qwiic connectors offer a simple daisy-chainable I2C interface to your main system. For a more permanent setup a standard 0.1-inch spaced plated through-hole (PTH) header breaks out the power and I2C pins for a soldered connection. This breakout gives you a reliable long-lasting way to track formaldehyde levels without complicated wiring.