As shown below, it is a circuit diagram of a portable gas detector. The portable gas detector circuit is used mainly in electrochemical sensors, dual-channel micro-power amplif
iers ADA4505-2 configured in a constant potential (U2-A) and transconductance configuration (U2-B) under use. The amplifier power consumption and very low input bias current, the constant potential portion and transconductance section are all good choices. Each amplifier consumes only 10 A, so the battery life is very long.