What is a Diode?
A diode which passes only the electric current of a particular polarity from one side. This is used for rectification and switching.Several types of diodes are used in electronic instruments and gadgets. Chip diodes are used in mobile cell phones. Those are surface mount devices (SMD). Surface mount devices are soldered with special soldering technique
Facts about Diodes
- Indicating in schematics of Diode: D or V or PD
- Function:ConvertingAC to DC and Do the Switching.
Types of Diode in Mobile Phone and their Function
1. Signal Diode
This type of diode is used for detecting signals. These diodes are made of glass. A red ring on the terminal marks its cathode. These diodes are available in following numbers – IN4148, IN34, OA79 etc. SMD signal diode is also available in black colour.

2. Zener Diode
This is a special type of diode made with silicon which is used to keep the output supply stable. Zener diodes are used to stabilize voltage. It is represented by “Z”.
Zener diode is recognized by its “Zener Volt” like 3.0VZ, 3.9VZ, 5.1VZ, 6.2VZ etc.
