Home Chapter 5 Using the multimeter to test a diode
Using the multimeter to test a diode


In this activity, you will learn to build a circuit using a diode and discern the function of a diode.

Parts needed:

2 Diodes
Multimeter with diode tester

Building the circuit:

  1. Set your meter to the Diode reading area.


    Use this setting to measure the bias of the diode.


  1. Place your diode in the board as shown below.

    Place the diode in the breadboard like this.


  3. Use your multimeters diode setting to measure the voltage drop that the diode will create across this circuit. The multimeter provides the voltage necessary to get a reading and functions to tell you what the voltage drop is. If you put your red lead closest to the white band, of the diode as below you will see the number 1 and this is indication that you have the diode in reverse bias.
  4. If you put the black lead closest to the Cathode or white band of the diode than current can flow and you will get a reading. What is the voltage you read? ___________ remember a mV is one thousandth of a volt)
  5. Now put two diodes end to end as you did for creating a series circuit with resistors and make sure the white bands of the cathode are in the same direction. What is your voltage drop with the two diodes added together?______________

    Image of a multimeter in reverse bias, which will produce no current flow on the diode.



    1) Name the three most common passive components.
    _________ _______________ ______________

    2) Why are active components called active?


    3) Define a semiconductor.


    4) What is doping.


    5) What are the two kinds of doping in semiconductors?



    6) What kind of semiconductor is formed when you add phosphorus?



    7) What kind of semiconductor is formed when you add boron?



    8) Name three uses for diodes in circuits?