Starting Electronics

Starting

electronics

NPN

The

2N3053

transistor is known as an NPN transistor

because

of the

fact

that a thin layer of P-type semicon-

ductor material is sandwiched between two layers of

N-type semiconductor material. The construction and

circuit

symbol of an NPN transistor are shown in Figure

8.10(a).

You may have worked out that there is another

way to sandwich one type of semiconductor material

between two others — and if so you would also have

worked out that such a transistor would be called a PNP

transistor. Figure

8.10(b)

shows a PNP transistor con-

struction and its circuit symbol. The only difference in

the circuit symbols of both type ...