SEN0661

SEN0661 is a Gravity: SFA40 formaldehyde (HCHO) sensor (0–1000ppb, high accuracy ±20ppb). This is a high‑precision electrochemical module built for accurate formaldehyde monitoring in indoor environments. Powered by the Sensirion SFA40 sensing chip, this Gravity‑series air quality sensor selectively detects HCHO molecules while minimizing interference from common household vapours such as alcohol or perfumes. Integrated SHT4x temperature and humidity sensing enables automatic environmental compensation, delivering stable and reliable readings for air monitoring systems. With a convenient Gravity I2C interface compatible with Arduino platforms and other development boards, this environmental sensing module integrates easily into smart home projects, HVAC monitoring equipment, and experimental air‑quality instrumentation.

• Zero false alarms with selective electrochemical detection
• Laboratory‑grade sensitivity down to 20ppb
• Integrated temperature and humidity compensation
• Extremely low cross‑sensitivity to ethanol (<0.3%) to prevent false alarms
• Integrated SHT4x sensor for temperature and humidity compensation
• Simultaneous output of HCHO concentration, temperature, and humidity
• Gravity I2C interface for easy integration with microcontroller platforms
• Supply voltage range from 3.3 to 5V
• Operating temperature range from 0 to 50°C
• Operating humidity range from 10 to 90%R.H

Contents

Gravity: SFA40 HCHO sensor, Gravity 4pin sensor cable.