Uses and key applications of different semiconductors diodes

Diodes are also called semiconductor diodes and one of the most basic yet important devices used in electronic circuits. This device is a dual-terminal electrical check valve, which allows electric current to flow in a single direction. The most common material used to make a diode is silicon and germanium.

The most common use of diode is rectification, meaning converting AC to DC. Since diodes come with a number of properties and features, they can be used in several applications. These properties are altered to create diverse types of diodes. Today, there are different types of diodes with diverse characteristics in terms of shapes, sizes and properties.

Different types of diodes:

An electrical circuit uses different types of diodes depending on its requirement and design. Diodes meet different device requirements and can be used to perform different functions because of their diverse sizes, shapes and properties.

Some of the key types of diodes include Small single diode, Large Signal Diode, Zener diode, Varactor diode, Step recovery diode, Tunnel diode, Shockley diode, PN Junction diode, Laser diode, Gunn diode, LED diodes and more.

Key applications and use of diodes:

We all make use of diodes in our day to day life; the majority of the electrical devices that we use feature a set of diodes. Here are some of the most common but important applications of diodes.

• Rectification:

The diodes were first used in radios and power supplies for rectification in order to transform AC signal into a single-directional DC signal (i.e. pure audio signal). Diodes are primarily used in two kinds of rectifications such as half-wave rectification and full-wave rectification. Half-wave rectification is the process of converting just half a wave of an AC signal into a DC signal. To achieve this form of rectification, only a single diode is used, but there is also a possibility of losing half of the signal. In the full-wave rectifier process, the complete AC signal is transformed into a DC signal. This can be achieved by arranging four diodes in a bridge rectifier arrangement.

• Voltage reference:

Several electronic circuits use Zener diodes as voltage guide to provide a steady voltage for biassing. In different electronic circuits, the Zener diode is used as a voltage guide to provide a steady voltage for biassing. In reverse bias, the diode acts like a voltage regulator and maintains a stable voltage over a larger range of current.

• Frequency mixer:

A frequency mixer circuit generates a new signal whose frequency is equal to the difference or sum of the two input signals. Diodes are used to shift the signal's frequency in frequency mixers. For instance, diodes shift the signal frequency for modulation or demodulation in a superheterodyne receiver.

• Switch:

Another common use of diodes is as a switch in a device or logic gates circuit. In forward bias, diodes turn on the current and turn it off in case of reverse bias. RDL logic mostly makes use of diodes. While this architecture is no longer used in modern circuits, it can be used to create simple logic gates with the use of diodes and resistors.

• Light source:

LED and Laser diodes transform electrical energy to light energy. The LED emits divergent light, whereas the laser diode emits a converged pulse. LED diodes are utilised in illumination systems like flashes, and more. Laser diodes, on the other hand, are utilised in pointers, printers, optical communication, scanners and more.

• Light and temperature sensors:

Many diodes are used to detect light and temperature in the systems. To monitor heat or temperature changes in microprocessors, the thermal or Peltier diode is widely considered. Photodiodes sense light and convert light to electrical energy. Smoke detection, optical communications and IR detector systems make use of photodiodes.

• Demodulator or diode detector (AM Envelope detector):

Diode with a capacitor is the cheapest and easiest circuit used for demodulating an AM signal. The diode detects the audio message signal that is stored in the envelope of the AM modulated signal because it permits only the positive half-cycle of the signal.

• Source Isolation:

An optoisolator, also known as an optocoupler, is a device that supplies signals between two circuits with the use of diodes, primarily IR diodes or Laser diodes, and a photosensor. The source circuit and the controlled circuit are not connected through any kind of electrical interaction. As a result, it protects the source from high voltages.

• Solar or Photo-Voltaic Cell:

Solar panels use photovoltaic cells to transform solar energy into electric energy. The photodiode and photovoltaic cell are different because a photodiode needs a reverse biasing, while the photovoltaic does not require any biasing.

• Clipper:

Clipper is a diode-based circuit that shapes the waveform of a signal by clipping or cutting a share of the positive half, negative half, or both halves of the signal. This circuit makes use of diodes to cap the voltage at a specific stage.

• Circuit protection:

A protection diode is used to safeguard a circuit from reverse current flow, which can damage the components or the source. Diodes also safeguard the circuit against reverse polarity that can occur in a battery. Special diodes such as TVS are used to secure the circuit from high voltage spike conditions.

Every type of diode has different uses and its own set of advantages. While some of the diodes are mostly used in a number of applications across several domains, others have limited applications. Many people also use simple diodes such as laser diodes, LEDs and others to conduct small experiments or build circuits at their homes or workplace. Diodes are easily accessible at India's one of the best online shopping sites on Moglix at affordable prices.

Diode: FAQs

Q. How do diodes work?

A. Diodes pass current in a single direction and are made using semiconductor materials like silicon, gallium arsenide or germanium. Diodes are two-terminal devices with a positively charged p-type (anode) and negatively charged n-type (cathode). The anode produces a larger quantity of electron holes whereas the cathode produces numerous free electrons during the doping process. Both the holes and free electron holes meet at a junction p-n, where n-type free electrons fill up the p-type holes, creating a depletion region. This region works like an insulator resisting current flow.

Q. What are the types of diodes?

A. There are different types of diodes, each having a unique application and function. Some of the types include zener diode, pin diode, gunn diode, LED diode, schottky diodes, vacuum diode, crystal diode, varactor diode, laser diode and more.

Q. Are diodes AC or DC?

A. Diodes work on DC supply as they pass current in one direction. They can also work on AC supply but require an antiparallel connection of two diodes.

Q. What's the difference between a diode and a Zener diode?

A. A diode works in one direction whereas a Zener diode works in both forward and reverse bias conditions. A standard diode can get damaged if used in reverse bias mode but a Zener diode is designed to operate in a reverse bias condition without getting damaged.