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Hello everyone, in this lesson we will learn about diodes

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First of all, let's get to know the diode

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A diode is the most basic semiconductor component

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It is widely used in life, such as light-emitting diodes

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The LED lights and traffic lights on the roadside are made of light-emitting diodes

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The two diodes on the right are widely used in circuits.

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Diodes have a very important feature in appearance, that is, one end is marked

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The marked end represents the cathode of the diode

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The composition of the diode is very simple,

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consisting only of a P-type semiconductor and an N-type semiconductor

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P-type semiconductor

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The meaning of P is Positive, representing the positive pole

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The N in the N-type semiconductor represents Negative, representing the negative electrode

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We need to remember that P is positive and N is negative

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Then the P-type semiconductor is the positive pole of the diode,

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and the N-type semiconductor is the negative pole of the diode.

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Why do diodes have positive and negative poles?

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That's because diodes have a very important characteristic, unidirectional conductivity

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A diode only allows current to flow from positive to negative, not from negative to positive

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When the P stage is connected to positive electricity and the N stage is connected to negative electricity,

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the diode can be turned on, and current flows through the entire circuit.

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However, when the N stage is connected to positive electricity

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and the P stage is connected to negative electricity,

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the diode is in a cut-off state, and no circuit flows through the circuit.

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This is the unidirectional conductivity of the diode