Technology and the demand for smaller and smaller electronic components continue to drive the market for more compact and efficient toroidal inductors. Already favored because of their small, compact donut-shaped design and their efficiency, these are the go-to option in almost all modern electronics when it comes to inductors.
However, with the traditional options in the design and manufacturing of toroidal inductors, there have been limits on how efficient and small these components can be. In the past, the restriction was in the single layer winding around the core. The actual turns or the amount of winding was restricted based on the inner diameter of the core. The wire could only be packed so tightly together in the single layer based on the smaller inner diameter rather than the larger outer diameter of the shape.
New Designs in Wire
One option that is being used in many different types of toroidal inductors is the change from traditional round wire for the winding to a rectangular wire. This can be smaller in overall width and still have the capacity of the round wire. When correctly oriented on the core, more wire, due to the smaller width, can be placed around the core regardless of the interior diameter.
To prevent issues with the wire twisting and actually ending up positioned the wider way across the surface of the core, the wiring is done in sections. This is a superior option that may allow the inductor used to be even smaller than the already reduced size from the standard inductor.
The Challenge of Multiple Layers
With new technology, there is less interest in moving forward with a multiple-layer winding around the core. With the multiple winding option, there is an increase in electrical noise in the inductor, which often results in the need for an additional inductor in the design. There is also less opportunity for the correct start and finish gap for the windings on the multiple design, which in turn is a concern for additional noise.
Although the multiple winding option will provide the increase in efficiency, the need for the additional inductor, which can also be toroidal, takes up more space in the electronic and also adds to the cost, weight and size of the system.
With ongoing developments in all types of inductors, particularly in the ever shrinking electronic components of today, designers have more options in quality components to consider. Before making a choice on an inductor be sure to take a look at what is new, you may be surprised at what is available.
