Diodes are often used for rectifying waveforms. There are various types of diodes. For example, a photo diode is the one which allows the current to flow when light strikes it. These types of diodes are mostly used as light detectors. A diode is also known as a rectifier. A zener diode is also a type of diode that allows reverse current to flow through it when the voltage exceeds the breakdown voltage known as 'Zener Voltage'.
It is a heavily doped diode with a very narrow depletion region. These types of diodes use the beak-down properties of a PN junction. Due to its unique properties, it can also be placed parallely across a load and used as a voltage regulator. These diodes have very accurate and specific reverse breakdown voltages. It is important to note that a zener diode works like an ordinary diode on forward bias. However, on reverse bias, leakage current starts to flow through the diode.
This leakage current increases with the reverse voltage. At a definite reverse voltage, leakage current starts increasing suddenly.
This particular voltage is known as the break down voltage of zener diode or the 'zener voltage'. The current that is increased suddenly is also referred to as a zener current. A zener diode can be easily distinguished from regular diodes by its code and breakdown voltage Zener voltage which are clearly printed on it. A diode is a type of electrical device that allows the current to move through it in only one direction.
Difference between Diode and Zener Diode. Key Difference: A diode is a type of electrical device that allows the current to move through it in only one direction. A zener diode is a heavily doped diode with a very narrow depletion region. It permits the flow of current in the forward direction and also in the reverse direction.
Comparison between Diode and Resistor: Diode Zener Diode Definition A diode is a type of electrical device that allows the current to move through it in only one direction. V slightly different than jd's, negative resistance! A diode is a semiconductor device which is formed when two alternative semiconductors are joined together i. A diode is a current controlling device which is used to control the current in one direction.
It is used for applications like Switching, Rectification , Clipper circuits , Clamper circuits , Voltage multipliers , etc. The P-layer can be considered as a positive layer because it has holes in the majority whereas N-layer is considered as a Negative layer which has electrons in the majority.
A diode is similar to a switch it has two modes of operation. When the diode is forward bias it behaves like a closed switch ON Switch , and when the diode is reverse bias it behaves like an open switch Off switch. When the P-type material is connected with a positive terminal of the battery and N-type material is connected with a negative terminal of the battery then the diode is said to be as Forward bias.
When the N-type material is connected with a positive terminal of a battery and P-type material is connected with a negative terminal of battery then the diode is said to be as Reverse Bias. During forward bias of the diode, the diode does not conduct immediately, but after a unique forward voltage, it starts to conduct. That forward voltage is commonly known as Diode knee voltage. If the diode is made up of silicon material than the knee voltage is 0.
During reverse bias of diode, the depletion layer starts to widen. Hence a wide depletion region has more resistance for the movement of majority carries thereby electric conductivity is very low.
Therefore; no electric current flows in reverse bias of diode. But the minority carriers can flow during reverse bias condition, constituting a very small current in the diode, that small current is temperature dependent. If the reverse bias increase beyond the value of temperature also increases and the minority carriers also increases, which can cause the diode to damage hence reverse bias condition is not used in diode operation.
The Zener diode is a special purpose diode which is always operated in the breakdown region. It has the special ability to allow the current to flow in forward direction as well as in the reverse direction, The Zener diode is highly doped as compared to the normal diode. In terms of the construction , the Zener diode is constructed similar way as a normal diode is constructed; the only difference in terms of their construction is that a diode is less doped as compared to a Zener diode.
During the reverse bias of the Zener diode, the depletion layer starts to reduce , because a Zener diode is a highly doped diode hence it has very thin depletion region , hence the electric conductivity is high.
When the reverse voltage reached at breakdown region the current start to increase in reverse direction and Thus, a Zener diode behaves as a voltage regulator. The Diode and Zener diode are different from each other with respect to their symbols, construction, operations, and applications, a major difference between diode and Zener diode is the electric current conduction normal diode can conduct in one direction whereas Zener diode is able to conduct in both forward and reverse direction.
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