A Watchdog Sensor for Assuring the Quality of Various Perishables with Subthreshold CMOS Circuits

Abstract

We developed a CMOS integrated-circuit sensor that emulates the change in quality of various perishables. This sensor is attached to perishable goods such as farm and marine products and is carried from producers to consumers along with the goods. During their distribution process, the sensor experiences the surrounding temperature and emulates the deterioration of the goods caused by the surrounding temperatures. By reading the output of the sensor, consumers can determine whether the goods are fresh or not. This sensor consists of subthreshold CMOS circuits with a low-power consumption of 5muW or less