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A guide on PCB transformer


What is PCB transformer

Transformers found to contain PCB at concentrations of more than 500 parts per million are referred to as PCB transformer. They have an extremely high proof voltage. They can be used on the PCB to offer safe electrical insulation for the input as well as output terminals.

What materials are PCB transformer made of

PCB Transformer is a magnetic component used in electromagnetic induction to transfer power from one circuit to another. The PCB transformer is made up of three parts: two coils of wire, known as the primary and secondary windings, and a laminated iron core. The iron core is surrounded by an insulated sheet called the bobbin.


The primary winding of the PCB transformer is connected to an alternating voltage source (such as 120 VAC). This alternating voltage induces an alternating current in both sets of windings. Since the inductance of each set of windings opposes any change in current, the net current through both sets of windings remains constant and produces no magnetic field at all.

In contrast, when a direct current flows through one set of windings (the secondary winding) it induces a magnetic field that can be detected by placing a compass near it. When this happens, we say that an electromagnetic field has been established between these two points; or more simply stated: there is current flow through this circuit (turning on lights or motors for example).

What is PCB transformer composition


The PCB transformer is composed of a core, a winding, and an outer layer. The core is made of ferrite, which provides high permeability and high saturation magnetic flux density. The winding is made of copper wire or aluminum wire, which has a large current carrying capacity. The outer layer is made of lacquer or resin, which protects the windings from moisture.

How does transformer work PCB

PCB transformer is a type of electrical transformer that works by transferring energy from one circuit to another. Power is supplied to the primary coil of the transformer by power source while the secondary coil is connected to the load. The primary coil creates a magnetic field, and the secondary coil is inductively coupled to the primary coil. This causes the secondary coil to produce a current.

The primary coil is wound around the magnetic core, and the secondary coil is wound around the primary coil. It makes the secondary voltage greater than the primary voltage.

What is a non PCB transformer

A non-PCB transformer has a PCB concentration of less than 500 ppm. It is a device that converts a voltage of alternating current (AC) into direct current (DC).

Some common uses of non-PCB transformer are as follows:
◆ They are used to change the overall voltage of a circuit, either to increase or decrease it.
◆They can also be used to isolate circuits, which helps protect components from damage and keeps them from being damaged by voltages outside their safe range.
◆ They are vital components in electronic devices such as radios, televisions, and computers.

What liquid is inside a PCB transformer and what that used for

Mineral oils (paraffin, naphthenes, and aromatic oils) are the liquid that is consumed in transformers. Mineral oil is preferred because it makes it simple to satisfy the electrical and chemical requirements of the transformer. Other fluids like R-temp and Askarel may also be used.


Protecting the transformer equipment, which includes the wires and iron core, is the major function of transformer oil. It also serves as an insulating medium by preventing harmful chemical processes, particularly oxidation.

The disposal of heat is another function of transformer oil. Although the transformer depends on alternating current, some factors result in significant heat creation even if there aren’t any moving elements in the transformer. If the oil is unable to absorb this, problems, including possibly hazardous and even explosive consequences, may occur.

The main PCB-Mount transformer Specifications

Some of the most important specifications to consider when choosing a PCB mount transformer are:

★ Primary and secondary ratings:

The rating describes the magnitudes of the primary and secondary current and voltage. You must first verify the output voltage. The next step is to determine whether the design current is below the transformer limit. Also, keep in mind that the circuit will release more heat if greater power density there is.

★ Power efficiency and rating:

The maximum power rating of a PCB mount transformer is the maximum amount of power that the transformer can handle. This is typically measured in watts. It is important to choose a transformer with a power rating that is high enough to handle the power requirements of your circuit. If the transformer is not rated for the required power, it can overheat and be damaged.

★ Mounting fashion

In the past, PCB transformers were mounted on the PCB using through-hole technology. However, this method is no longer feasible due to the increasing complexity of PCB designs. As a result, surface-mount technology (SMT) has become the preferred method of mounting PCB transformers.
Cooling System.

In order to dissipate the heat generated by the transformer, manufacturers have come up with different cooling solutions. The most common technique is the use of a heat sink which are usually metals like copper and aluminum.

Do all transformers contain PCB

All transformers do not contain PCB. Some transformers are filled with oil, while others are dry-type. Let us discuss it one by one.

One type of transformer that does not contain PCB is an oil-filled transformer. Oil-filled transformers are filled with a dielectric fluid that helps to cool and insulate the transformer. These transformers are typically used in high-voltage applications, such as power plants. One downside of oil-filled transformers is that they have a higher risk of leaking than dry-type transformers.


Another type of transformer that does not contain PCB is a dry-type transformer. Dry-type transformers are filled with air or another gas, rather than oil. These transformers are typically used in lower-voltage applications, such as homes and businesses. Dry-type transformers are less likely to leak than oil-filled transformers, but they are not as effective at cooling the transformer.



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