ESP32 Forum

Hi everyone!

I want to connect the Nemoto NE4-NO2 NO2 gas sensor to an ESP32. I read that it cannot be connected directly and that an AFE (Analog Front-End) module is needed.
Does anyone have a schematic using the AD8628ARTZ-REEL7 op-amp or a similar solution? Or other ideas on how to interface this sensor with an ESP32?

AD8628 is a good op amp candidate. It has ultra-low input bias, rail-to-rail, works from 2.7–5 V. It is suitable for 3.3 V systems. It's a single amplifier device. So you’ll need two op amps (two AD8628 chips) or use a dual device (such as AD8629) if you prefer.