Diode explanation

A diode is a semiconductor device that allow current to flow in only one direction. Depending on the type of diode, it has uses as voltage rectifier, indicator and regulator.

Theory checklist:

• The P-N junction
• Forward and reverse bias

Modes of operation:

• Rectifier
• Diode as reference voltage
• The zener voltage regulator
• The led diode indicator
• The varicap variable capacitor
• The photodiode light sensor