This paper introduces the working principles of the digital microscale dissolved oxygen analyzer and sensor. And it also introduces the design of the work system's hardware circuit, signal acquisition circuit and temperature compensation circuit. The instrument features stability and anti-interference with the singlechip as a core to control and process signal. After compared with the dissolved oxygen analyzer made in Switzerland Orbrisphere Company, the self-made dissolved oxygen analyzer was

more »

... roven to reach the precision level of μg/L. The uncertainty is ±3%μg/L from the experiments, it shows the new-style electrochemical sensor can be widely used to detect dissolved oxygen in boiler feed water in power plant.