Different cases had also taken for all the components in the present circuit to obtain an optimal value, which was maximum by first keeping the input voltage as constant. After studying on different feedback loops, we have found that the negative feedback loop used in the present circuit cancels out the noise and varies linearly. From the different used op amp, it has been found that without a feedback loop, the op amp works as a comparator. An operational amplifier (op-amp) is used for the simulation in Proteus software. The present study aimed to further amplify the electric signal to enhance the sensitivity of the sensor by tuning the amplifier-circuit. In resistive type humidity sensors, two electrodes are placed in an inter-digitized pattern to enhance the contact area, in which resistivity changes with moisture absorption in between the electrodes.
Therefore, it is essential to investigate on improvement of sensitivity of a sensor. However, the tiny change in humidity is very difficult to measure by conventional sensors or hygrometers. Particularly, a tiny change in humidity in prosthetic devices alters biological harmony of the living society. The emerging human comfort life attracts the monitoring of humidity in atmosphere.
