There are several types of diodes for the most diverse applications, but without a doubt, the diode most used in the world of electronics is the rectifier diode! This is easily explained as it serves most applications used in electronic projects. It is worth remembering that the main characteristic of a diode is to allow the passage of electrical current in only one direction. In the diodes, current flows from the anode (+) to the cathode (-).
What is the rectifier diode?
The rectifier diode is a semiconductor device used to convert signals from alternating current to direct current, maintaining only a semiconductor of the sine wave that is the characteristic of alternating current, hence its name “rectifier”. In addition, the rectifier diode can normally be used as a diode for any application that requires current to flow in only one direction, for example, it can be used to prevent the inverted connection to the power supply of a 12 volt TV connected to the car battery.
In this case, the TV could burn if the polarities of its power supply to the battery were reversed, but with the diode installed correctly, the TV would not work if the terminals were connected inverted. Therefore, it would be enough to invert the polarity of the terminals for it to work correctly and safely.
How the rectifier diode works
The figure below shows how the rectifier diode eliminates one of the semicircles of the sine waveform, notice that the sinusoidal signal is being applied to the anode of the diode, consequently, in the anode, we will have a resulting waveform with only the positive semicircle.
If we invert the polarity of the diode by replacing the anode with the cathode, we will see that the resulting waveform at the anode will only be the negative semicircle.
The conversion of alternating current to direct current is widely used to properly supply electronic circuits that use components such as integrated circuits, LEDs and transistors since they usually work powered by direct current, battery chargers also require a rectifier circuit because batteries and Batteries of all types are components that store energy exclusively in the form of direct current and can explode if they are connected to an alternating current source.
Types of the rectifier diode
The rectifier diode can be presented in several forms or encapsulations, this varies according to its maximum power. In the image below you can see some of the different types of rectifier diodes that exist on the market.
Rectifier bridge with diodes
It has already been seen that a diode eliminates a semiconductor from alternating current, but the resulting waveform is not stable but is formed by pulses, which despite being already direct current does not have a constant voltage, being necessary to use the two semicircles to form a DC source with the most stable voltage possible. To solve this issue we have a combination of rectifier diodes called RECTIFIER BRIDGE, this combination is formed by four diodes and each pair of diodes is responsible for rectifying a sine wave semicircle. Diodes D1 and D2 conduct on the positive semicircle and diodes D3 and D4 conduct on the negative semi cycle, to make the voltage even more stable we can add a capacitor after the rectifier bridge circuit,
The rectifier bridge circuit can be assembled as in the figure or it can be acquired as a single component form where we have several diode rectifier bridges.
The rectifier diode is the main component of the circuit that converts alternating current into direct current, as this circuit is widely used in electronics, the rectifier diode is widely found in power supply applications, in addition, the rectifier diode can also be used as a diode general use, especially when high electrical currents are required. It can also be found in several different enclosures by means of the maximum power required by the circuit, it is also worth remembering that the main characteristics of the rectifier diode are the maximum current and the maximum voltage that it can support at its terminals.