Uses of Zener Diode

May 21, 2024

59

Table of Contents

Introduction

A silicon semiconductor device is known as a Zener Diode. It permits the current flow in either a forward or reverse direction. It consists of a P-N junction, which is required to conduct reverse direction current after reaching a specific voltage. A Zener diode can continuously operate in a reverse-bias mode as it has reverse breakdown voltage without getting damaged. Across the diode, the voltage drop remains constant, which helps make the Zener Diode much more suitable for voltage regulation.

Breakdown Voltage is the voltage that is measured after the voltage exceeds a certain threshold. The current flows in the opposite direction. This breakdown voltage is also known as Zener knee voltage.

Zener Diode Uses

There are numerous uses of Zener diodes related to voltage. Zener diodes are heavily doped silicon semiconductors that allow equivalent current flow in the forward and backward directions.

The Zener Diode works as a conventional diode when provided with the forward one-sided voltage. If an opposite one-sided voltage is provided, a small amount of current is allowed to flow. In this case, the voltage is not a Zener voltage. After the reverse, one-sided voltage is provided, the Zener diode reaches Zener voltage, after which the flow of current increases. The different uses of Zener Diode are listed below.

1. Used as a Voltage Regulator

In a Zener Diode, when the load voltage (also called heap voltage) is the same as the breakdown voltage, there is a limitation in the flow of current through the diode in the resistors connected in series since while the diode is conducting, there is an excessive amount of voltage. In such a situation, the disturbance generated in the diode gets suppressed by decoupling capacitors across the diode. This arrangement increases the heap voltage to the breakdown voltage. Hence, it works as a voltage regulator.

2. Shifting Voltage

Zener diodes are also used to convert a signal from one voltage to another while maintaining a steady output voltage. Zener diodes are an ideal component for operation due to this function. They can easily maintain a steady output voltage in the breakdown region. As a result, they are widely used across industries where this functionality is highly desirable.

3. Protection from Overvoltage

When the heap voltage reaches the breakdown voltage, a voltage drop is caused across the resistor. It ultimately causes a short out to the ground, detaching the load voltage from inventory and opening the breaker. As a result, it offers better protection from overvoltage. It enhances its utility manifold.

4. Clipping the Circuits

Clipper circuits or trimmer circuits prevent the output signals from going beyond the specified value without affecting the input signals. The Zener Diode modifies and shapes AC waveform clipping circuits. With this help, in one section, the AC waveform is limited to provide protection and shape it. The clipping circuits are mainly used in FM and TV Transmitters to remove any interference.

Things to Remember Related to Zener Diodes

There are a few of the points that are crucial for Zener Diodes and their work. You must know these points in detail to use them for complex calculations. Some of these essential points are as follows.

A Zener Diode is a P-N junction that helps conduct reverse direction current after reaching a specific voltage.
In the circuits containing the AC input source, Zener Diodes limit the output voltage’s peak to Zener voltage.
The Zener Diodes are also used as the voltage regulator in a DC circuit. Due to this, the voltage across the circuit remains constant despite a higher variation.
In power supply and other circuits, a Zener Diode can also be used as a constant voltage source. For this, the input voltage should increase the Zener voltage, and the series resistor must have a minimum value to allow the device to conduct maximum current.
When the current flowing in the opposite direction exceeds a certain threshold, it is called Breakdown Voltage or the Zener Knee Voltage.