The BJT (bipolar junction transistor) is an active electronic component with three terminals (base – collector – emitter). Its interior is composed of two alternately doped semiconductor junctions n and p. The two types of BJT that can be obtained are: the npn model and the pnp model.
We measure the voltage VD across the diode, the voltage VR across the resistor and the current ID flowing in the circuit for each value of Vi ranging from 0V to 2V with 0.1V intervals. Finally we graphically represent VD and VR.
With a multimeter it is possible to check the integrity of a diode. The “diode test” function allows you to measure the voltage drop across it. By connecting the anode to the positive and the cathode to the negative, we will read the voltage drop value on the multimeter. By reversing the link, we will not read any values.
The diode is a passive, non-linear electronic component consisting of a p-n junction. The lead connected to the p junction is called the anode, while the one connected to the n junction is called the cathode. The reference of the leads on the real component is given by a black or silver line which indicates the cathode.