Key Design Advantages of Toroidal Transformer Units

Toroidal or doughnut transformers are one of the main types of transformer on the market. There are a number of advantages offered over other transformer types.

Key Design Advantages of Toroidal Transformer Units

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These advantages make the toroidal family of transformers the best option for certain applications. Some of the key advantages that the toroidal design offers over other transformer types are as follows.

Smaller and Lighter

This kind of transformer is smaller and lighter than standard transformers, and indeed smaller and lighter than most other transformer types available. At a time when electronics, in particular, strive for compactness this is very valuable indeed.

While there are some other transformer types that could rival toroidal transformers, most are either less efficient or more expensive to produce without much in the way of real advantages. As a result, most are also less easily obtainable than toroidal types, which are readily available from many outlets such as Siga Transformers.

Low Stray Magnetism and Low Noise

These two factors are more closely related than you may think, as magnetism is integral to the process that makes other transformer types produce that annoying hum. In situations where such humming is undesirable or outright unacceptable, doughnut transformers are the solution.

At the same time, they produce relatively little in the way of “stray” magnetic fields, which can interfere with other equipment. This makes them ideal for applications where such interference would be a concern, as they reduce both overall risk levels of interference and the need for costly magnetic shielding. In highly sensitive applications, they can be used in conjunction with magnetic shielding for an extremely low risk of interference.


Transformers produce heat. This heat is wasted energy, but it can also be a problem in itself. When temperatures are important or heat-sensitive equipments or materials are being used, or when voltages are very high and therefore so is the level of heat produced by other transformer types, toroidal units can provide a practical and efficient solution.


The toroidal design is a very efficient one – much more so than the design of a typical “laminated core” transformer. Lack of air gaps, a layout that utilises almost all of the metal in the ferrous core and even distribution of windings can make for a transformer that offers a noticeable efficiency boost over most of the alternatives.