What is a Diode?How it works? Its uses and purpose.symbols and structure of a doode.

What is a diode: Diode means die electrod,means two electrod, which is based two terminals ANODE and CATHODE.Diode is a two terminal semiconductor device. It is works only forward bias.
     Diode did not work in revese bias.it is two terminals,Anode and Cathode.various types of diodes,like semiconductor diode,rectifier diode,zener diode,led diode etc.

See the picture of diode given above.in the diode,the ring side terminal is Cathode also.and other side is a Anode terminal.
See the pic.given below.diode on the pcb in working mode.

Types of diode: Different types of diodes in electronics.

1.Rectifier diode

2. Zener diode

3. Led diode

4. LDR

5. Photo diode

6. Schottky diode

7. Tunnel diode
8. Pin diode
9. Varactor diode

Use of diodes: Basically diodes are used in a rectifier cuicuits, for rectification.see above the types of diodes,each of every diode works in a different ways and purpose.
See given below
1. As a switching
2. Signal modulation
3. Voltage regulation
4. As a Signal demodulator
5. As a oscillator.
6. Detetion
7. As a limiter
8. Voltage controler
9.Variable capacitor
10. As a LED.

Structure of a diode: In the diode basically two junctions.
1. P type junction
2. N type junction.

Circuit symbol of a diodes:
1. Rectifier diode

2. Zener diode

3. Tunnel diode

4. Schottky diode

5. Light emmiting diode

6. Photo diode

Diode checking: Diodes are basically check on multimeters in ohm range. There are two terminals, ANODE(+)and CATHODE(-)in the diode.

     Multimeters positive and negative terminals put on the diodes positive and negative terminal.Multimeter will show a reading,if the diode is good condition.In other side diode did not show the reading on display. Because the diode is only work in forward bias.
     When diode give a beep sound on multimeter during checking,it is short condition.It is doesn't work properly.Diode is a allready open component.