Diodes are commonly used discrete semiconductor devices. It has many uses and purposes. Its operation is based on PN semiconductor junction characteristics. Depending on diode’s physical and chemical properties, it can behave very differently. Together with other electronic components diode can be used for voltage clipping, multiplying, rectifying, signal, demodulation, protection, and even more. Elektro-labs have written a pretty nice review of diode types and their common uses.
The simplest and probably most recognizable is regular diode which is used in switching, protection rectification circuits. Another common diode type is Zener which is used for voltage stabilization.
Here are some of the most common types of diodes, along with examples of part numbers:
- Rectifier diodes: Used for rectifying AC voltage to DC voltage. Example part numbers include 1N4001, 1N4007, and 1N5408.
- Zener diodes: Used for voltage regulation and overvoltage protection. Example part numbers include BZX55C5V6, BZX85C5V1, and 1N4733A.
- Schottky diodes: Used for low-voltage drop applications and high-frequency switching. Example part numbers include BAT54, 1N5819, and SB5100.
- Light-emitting diodes (LEDs): Used for lighting and indicator applications. Example part numbers include 5mm red LED, 3mm green LED, and 10mm blue LED.
- Varactor diodes are used for the voltage-controlled oscillator (VCO) and frequency modulation (FM) applications. Example part numbers include BB639E7904, 1SV149, and BB639.
- Tunnel diodes: Used for high-speed switching and amplification applications. Example part numbers include 1N3716, 1N3718, and 1N3719.
- Photodiodes: Used for detecting light and converting it into electrical signals. Example part numbers include BPW34, TEMD5110X01, and SFH203P.
- PIN diodes: Used for RF switches and attenuators and high-speed switching. Example part numbers include HSMP-3810, BAP55-04, and BAR64-02V.