What is diode | Diode definition

 

What is a diode?

A diode is an electronics semiconductor component or device, it is the most important component in any circuit, because it can protect against the wrong polarity connection of current to our circuit.

The diode made by silicone material, it has two terminals "Anode" and "Cathode", which diode mostly used their shape is like a cylinder.

 

This white line present on any diode which denoted to Cathode, means which side has white line there is Cathode terminal in easy word it show Negative terminal of any diode.

The diode rating in "Amps" such as 1 amp, 3 amp, 10 amp and so ‘on, diode support values measure in amp, because it always use in series it can't use in parallel, if it use in parallel then circuit may be short circuit, it is always used in series so this rating we take always in Amp.

The diode depends entirely on Amp, it has voltage range always high, a typical use diode is capable of a maximum of 1000volts.

 Working of diode

The typically work of a diode is "AC" alternating current convert to "DC" direct current.

The diode used in all power supplies, for current changing, because we supply "AC" current to any power supply circuit, so diode first change "AC" current into "DC" current, then supply to forward the "DC" current, and power supply will working.

Another useful work of diode that it cannot flow current in reverse direction, it can control or stop to reverse polarity current.

You see in diagram that diode has two points, Anode and Cathode.

The Anode denoted to positive terminal, and Cathode denote to negative terminal, if we will connect positive wire of battery to diode's Anode point then diode will out current, and if we connect negative wire of battery to diode's Cathode so diode will give output current.

But if we connect positive wire of battery to diode's cathode then diode will not pass current to forward and like this vice versa.

This is very best work of a diode and most useful work, which is important for more to more any "DC" equipment, which can't support reverse polarity, such as transistor, capacitor, ICs, Battery, etc. Because we can save our "DC" equipment or component, by fit a small diode to any equipment.

 Types of diode

We have many types of diode, but we commonly use four types of diode.

• PN Junction Diode
• Light Emitting Diode
• Zener diode
• Schottky diode

1-PN junction diode

The PN junction type diode is normal diode which use mostly used in any electronics circuit, it has only two works AC to DC current converting and reverse polarity protection, which we discussed above. Also it we use for voltage dropping, because one Diode can drop 0.5 volt.

We use diode for speed control in juicer machine and grinder machine, etc.

2-Light Emitting Diode

The Light Emitting Diode is in fact its a "LED" the LED also a type of diode, because it will not glow in reverse polarity means LED will control to reverse current, if we supplied current in right way then current will pass through them and LED be glow.

3-Zener diode

The zener diode always use in reverse polarity, means it current flows in backwards.

Basically it use for like voltage regulator means it can keep stable voltage in any circuit, for this its rating in volts such as 1.5v, 2v, 5v, and so’ on.

Example:- we have 5v zener diode, if we supply 7v, 9v, or 12v, to zener diode, so zener will out only 5v to forward, and extra voltage zener will ground, means extra voltage be waste by grounded. So much value of zener there voltage will flow and extra volts waste. But its current capacity is very low, such as mille amp, it we use current supply to ICs or LED, because it required low voltage and low current.

4-Schottky diode

The scottky diode is similar to PN junction Diode, but it very low voltage drop in forward condition and it can fast switching, for this it mostly used in power supplies circuit.