Advantages of Photodiode | Disadvantages of Photodiode
This page covers advantages and disadvantages of Photodiode. It mentions Photodiode advantages and Photodiode disadvantages.
A photodiode is a type of photodetector capable of converting light into either current or voltage. The device operates in reverse bias and electric field developed across the p-n junction sweeps the mobile charge carriers to their respective majority sides. Hence a depletion region is formed. This barrier stops the flow of majority carrier and supports the flow of only minority carriers and hence leakage current flows.
The figure-1 depicts photodiode symbol and one such part from OSRAM.
Advantages of Photodiode
Following are the advantages of Photodiode:
➨Better frequency response
➨It can be used as variable resistance device.
➨It is highly sensitive to the light.
➨The speed of operation is very high. The switching of current and hence resistance value from high to low or otherwise is very quick.
Disadvantages of Photodiode
Following are the disadvantages of Photodiode:
➨Small active area
➨Rapid increase in dark current and it depends on temperature.
➨Require amplification at low illumination level.
➨Photodiode charateristics are temperature dependenta and have poor temperature stability.
➨Current/change in current is in small and hence may not be sufficient to drive the circuits, hence amplification is necessary in photodiode based circuits.