1. Diodes Benchmark Companies Inc PO Box 473768 Aurora CO 80047

2. Diodes Back Objective 1 Diodes 1. Identify the purpose of a diode 2. Identify different types of diodes 3. Recognize diode schematic symbols and reference symbols. Diode Construction 1. Describe semiconductor material 2. Identify N-type and P-type semi-conductor material 3. Describe forward and reverse biasing

3. Diodes Back Diodes are a critical part of electronics. In this section we will discover just how important they really are……... The symbol and notation of different types of diodes Junction DiodeZener DiodeLight Emitting Diode

4. Diodes Back Diodes come in several sizes and shapes. A typical identification method is as follows…. 1N914 A typical silicon diode with identifier Diode Solid State Device Type of Diode

5. Diodes Back Diodes allow current to flow in one direction, while preventing current to flow in the other direction. Electron Flow

6. Diodes Back Diodes allow current to flow in one direction, while preventing current to flow in the other direction. Reverse Bias (no current)

7. Diodes Back PN Diode symbols are illustrated above. The Positively doped material is represented by an arrow and is called the ANODE. ANODE

8. Diodes Back PN Diode symbols are illustrated above. The Negatively doped material is represented by a bar and is called the CATHODE. Cathode

9. Diodes Back Electron Flow (Forward Bias) It is important to understand the electron flow versus conventional flow of current. Conventional Flow of current

10. Diodes Back When in forward bias mode, the diode is a short Biasing the Silicon Diode + -

11. Diodes Back When in a reverse bias mode, the diode acts as an open. Biasing the Silicon Diode + -

12. Diodes Back PN Configuration of a forward bias diode Electrons are attracted into the N-type material and attract to the holes. Barrier Junction

13. Diodes Back PN Configuration of a Reversed bias diode As the diode is reversed biased, the attraction Of P-type and N-type is towards the outer edges. Barrier Junction

14. Diodes Back When in forward bias mode, the silicon diode has approximately a.7 volt drop across the junction Voltage Drops in the Silicon Diode FORWARD BIAS Electron Flow.7 volt drop

15. Diodes Back When in a reverse bias mode, the silicon diode acts as an open. Voltage Drops in the Silicon Diode REVERSE BIAS

16. Diodes Back Current Volts Characteristic Curve of a Junction Diode Current vs Voltage Reverse Bias Forward Bias.7V Knee voltage Leakage current Reverse Breakdown (Avalanche) Controlled Current Limit

17. Diodes Back Summary on Diodes Three types of Diodes were discussed Junction diode Zener diode Light emitting diode

18. Diodes Back Summary on Diodes Junction diodes contain: Anode (Ptype material) Cathode (Ntype Material)

19. Diodes Back Summary on Diodes Forward bias Diodes simulate a short Reverse bias Diodes simulate an open