Why do we use Zener diodes?

Zener diodes are used in electronic circuits for several reasons:

1. Voltage regulation: Zener diodes allow current to flow in both directions when the voltage across the diode exceeds the Zener voltage or breakdown voltage. This allows them to be used for voltage regulation by clamping the voltage at the Zener voltage level.

2. Overvoltage protection: Zener diodes can be used in overvoltage protection circuits to protect sensitive electronic devices from voltage spikes. When the voltage exceeds the Zener voltage, the Zener diode conducts and provides a path for the excess current to flow, thereby protecting the device from damage.

3. Reference voltage: Zener diodes can be used as reference voltage sources in circuits where a stable voltage is required. The Zener voltage of the diode is a fixed value that is not affected by changes in temperature or current, making it a reliable reference voltage source.

4. Amplification: Zener diodes can also be used as amplifiers in some circuits by using them in a common-base configuration. The diode's nonlinear characteristic allows it to amplify small input signals to larger output signals.

In summary, Zener diodes are used in electronic circuits for voltage regulation, overvoltage protection, reference voltage, and amplification. Their versatility and reliability make them an essential component in many electronic devices and systems.