Bipolar transistors

The circuits of insert of bipolar transistors.Planar n-p-n structure of the bipolar transistor.In a fig.The area of collector junction always is more than the area of emitter junction.The region of the emitter should have higher electrical conductivity, than basis and collector.The third electrode is common concerning an input and exit.Conditions of insert of the transistor.Four conditions of insert of the transistor are possible.In each of three circuits of insert of the transistor these parameters have particular magnitudes.Condition of saturation.