A P-N junction diode is a silicon. The P-N junction diode is the basic element for semiconductor diodes. One of the terminals is doped with p-type879 material and the other with N-type of material. The schematic symbol shown in the figure, P-N junction diode is made up of P-type silicon and N-type silicon semiconductor materials.
P-N junction diode is used in a variety of applications like LASER, solar cell, LED, digital logic design, DC power supply, etc. This article also gives many more application listed below.
Symbol of PN junction diode :
Application of PN junction diode :
- Light-emitting diode application
- Laser
- It can be also used solar cells
- It used in the detector as well as the demodulator circuit
- It is used in many circuit or diode-like, a switching diode, Zener diode, PIN photo-diode, varactor diode
- It is used as switches in digital logic design
- It can be also used p-n junction photodiodes
- It can be used as a rectifier in DC power supply
- It is also used clipping circuit
- It can be also used computers, radios, radars as wave shaping circuit
V-I characteristics of PN junction diode :
- When the anode is positive with respect to the cathode, the diode is to be forward biased. From Vs = 0 to total cut-in voltage, the forward diode current is very small.
- Cut in voltage is also known as threshold voltage or called turn-on voltage.
- For a lower power diode, the current in the forward direction increases first exponentially with voltage and then becomes almost linear.
- When the cathode is positive with respect to the anode, the diode is said to be reverse biased.
- In the reverse biased condition, a small reverse current called as a leakage current.
- The leakage current is almost independent of the magnitude of reverse voltage until this voltage reaches breakdown voltage.
- At this reverse breakdown, the voltage remains almost constant but reverse current becomes quite high limited only by the external circuit resistance.
- A large reverse breakdown voltage, associated with high reverse current, so power is lost and maybe diode is destroyed.
- This shows that the reverse breakdown of a power diode must be avoided by operating it below the specific peak reverse repetitive voltage shown in the figure.
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| V-I characteristics of a P-N junction diode This article also gives the various types of diode listed below: |