Functions Of Diode by Type

 

Types of diodes and functions of diodes in electronic circuits

The diode is a semiconductor component. But the principle of a diode is just a component that can conduct and block/inhibit electric current with 2 working conditions, namely forward bias and reverse bias.

We often know that the function of the diode is only as a voltage rectifier and things related to the voltage filter on the power supply. However, if we look further, it turns out that many diode functions are depending on the type of diode used, some of which are lighting, current control, and signal detectors.

There are two main materials used for diodes in the manufacturing process. Namely Silicon (Si) and Germanium (Ge). These two semiconductor materials have different voltage drops, namely, diodes made of silicon have a voltage drop of 0.7 Volts, while diodes made of germanium have a voltage drop of 0.4 Volts.

Functions of diode by type

Diodes have functions that cannot be replaced by other components in the electronic circuit. For this reason, we can find that almost all electronic circuits have this component. But at the beginning of its appearance in 1919 which was discovered by a scientist named William Henry Eccles, diodes functioned a lot as a component of rectifiers of AC to DC voltage.

But over time and its development, diodes also can be functioned as components of light generation, audio and radio signal processing, and heat/cold temperature generators.

 

1. Rectifier

Rectifier diode is a diode with the basic construction of the confluence of P and N (PN Junction). As the name implies, this diode functions as an AC to DC voltage rectifier on a power supply or power logger. The rectifier diode is also called the "normal diode".

There are 3 main configurations of a diode when used as an AC voltage wave rectifier. Namely the wave rectifier, the full wave rectifier and the full wave rectifier with the bridge system. Of the three configurations, the best is the bridge system, because in addition to using four diodes, the DC current produced will also be flatter.

2. Bridge Diode

A bridge diode is a diode consisting of four rectifier diodes combined into one diode that produces 4 legs, of which two legs as input and the other two legs  as output. One of the advantages of this bridge diode is that the rectifier circuit becomes more compact because we do not need to arrange the four diodes into one, because already on the bridge diode it has become one component.

Bridge diodes generally have specifications for larger currents compared to ordinary junction diodes. However, the specifications of bridge diodes for small currents also actually exist depending on the type and series of the component.

3. LED (Light Emitting Diode)

As the name implies, an led diode is a diode that can emit light through both electrodes that are electrified, in this case an LED diode can light up when it is electrified by DC current forward (forward bias). LED type diodes are one of the most popular types of diodes because they have a very large number of functions against electronic circuits related to lighting.

Some of the uses of LED diodes in electronic equipment are LED TVs, lights of new generations of car and motorcycle vehicles, indicators of instrumentation equipment, as walking displays (Running LED) and so on.

At this time, the use of LED diodes as lighting tools to replace ordinary lamps has become more and more, because LED diodes can emit much brighter light with the same power as other types of lamps. Automatically the use of LED diodes can save electricity use significantly.

4. SCR Diode (Silicon Controlled Rectifier)

The SCR diode actually consists of a schottky diode designed in such a way that it produces an SCR diode that has 3 legs with certain characteristics. SCR diodes are widely used as high-speed automatic switch circuits, inverter circuits, TL lamp circuits, and others.

The shape of the SCR diode is physically similar to that of a transistor in that it has 3 legs. But what distinguishes it is the name of the foot and the function of the SCR itself. The SCR diode consists of the Anode, Cathode and Gate legs. Briefly, the way the SCR diode works is that the current from the Anode will flow to the Cathode if the Gate foot is given a trigger.

5. Zener Diode

The zener diode is one of the diodes that has an active role in stabilizing the voltage in the power supply or power supply.  Unlike other diode installations, in the design of electronic circuits using zener diodes, it is installed under reverse bias conditions or reverse conditions from forward bias.

Zener diodes have a certain breakdown voltage according to their type and series. The most common unit of the zener diode type is directly showing the voltage read. For example, the 5V zener diode series for 5V. But there are also many series with certain unique codes according to the manufacturer and the region in each country of manufacture.

6. Laser Diode

Laser light in electronic equipment is the light produced by a diode. Almost the same as LED diodes that emit light, laser diodes are also one of the diodes that can emit light. It's just that this diode emits laser light, which is where this laser beam is a high-speed infrared spectrum radiation beam.

LASER stands for Light Amplification by Stimulated Emission of Radiation. Laser diodes are widely applied to scanner circuits, blueray devices, and laser cutters. Devices that use laser diodes will usually be more expensive if the light intensity and power of the laser are greater. Large-power lasers are highly used in light-based cutting devices.

7. Schottky Diode

The schottky diode is one of the special diodes. It is said to be special because schottky diodes have a lower forward or forward bias voltage than other types of diodes in general. Usually diodes have an advanced voltage of 0.6 to 0.7 Volts, the average schottky diode has an advanced voltage ranging from 0.2 to 0.4 Volts. The main ingredients of schottky diodes are chromium, platinum and tungsten.

Schottky diodes are widely used in high-speed switching circuits such as power supply switching and high-frequency radio detector circuits.

8. Peltier Diode

A peltier diode is a diode that functions to convert electrical energy into heat or cold energy through its cross section. Today peltier diodes are used in computer processor cooling devices, USB mini refrigerators, and others.

9. Tunnel Diode

Tunnel diodes are high-speed diodes that are widely used in microwave or microwave circuits. Technically, these diodes are made with semiconductors that are processed using quantum mechanical effects called tunnels.

Some examples of the application of this tunnel diode are in oscilloscope devices, televisions, and microwave frequency microwave microwave ovens.

10. Photodiode

Unlike led diodes that can emit light, photo diodes are sensors that can convert light energy into electrical energy through their two electrodes. Photo diodes are widely used as instrumentation tools based on incoming light inputs. In addition, photo diodes are also used as part of fiber optic or fiber optic communication because they have advantages in terms of high speed and wide bandwidth.

11. Varactor Diode

Varactor diodes are one of the unique types of diodes. Because this diode is made with semiconductors but can function like a capacitor. The varactor diode has capacitive properties such as a capacitor whose capacity value can change according to the given voltage control.

The varactor diode is widely used on radio and television oscillator frames. Usually the varactor diode is coupled with a capacitor and winding to generate frequencies.

12. Crystal Diode

Crystal diodes are one of the ancestors of modernized diodes. It is referred to as the ancestor of diodes because of the early discoveries of these diodes were crystalline diodes. Which diode is made based on the contact between the semiconductor crystal and a certain point that produces the confluence between P and N. 

Diodes of crystals are made of germanium that are widely applied as receiving radios (crystal radios), detector diodes, and certain parts of the circuit related to high-frequency radio.