Diodes are one-way valves for electricity. They allow current to flow in one direction only, making them vital for power conversion and protection.
How a Diode Works:
A diode has two terminals: anode and cathode. When the anode is at a higher potential than the cathode, the diode conducts. When reversed, it blocks current.
This behavior is called forward and reverse bias.
Types of Diodes:
- Standard PN Junction Diode: Used in rectifiers.
- Zener Diode: Designed to conduct in reverse beyond a breakdown voltage. Used in voltage regulation.
- Schottky Diode: Very low forward voltage drop, great for power applications.
- Light Emitting Diode (LED): Emits light when forward biased.
- Photodiode: Converts light into electrical current.
Key Specs:
- Forward voltage (typically 0.7V for silicon)
- Reverse leakage current
- Maximum reverse voltage
- Switching speed
Applications:
- AC to DC conversion (rectification)
- Voltage regulation
- Reverse polarity protection
- Signal demodulation
- Optical communication
Diodes are foundational in both analog and digital electronics. Knowing how to use each type correctly improves circuit reliability.
