Toroidal transformers are becoming increasingly popular due to their improved magnetic properties. The advantage of the toroidal (donut) shape is that due to its symmetry the amount of magnetic flux that escapes outside the core (leakage flux) is minimised, therefore it radiates less electromagnetic interference (EMI) to nearby circuits or equipment. EMI is of increasing importance in modern low power, high frequency electronics.
Toroid transformers can be made to a lower profile than a standard solenoid core transformer, allowing for equipment of similar power to be of a lower profile.
Features

• Lower electrically induced noise demanded by compact equipment.
• High efficiency enabling conservative rating whilst maintaining size advantages.
• The toroidal transformer is accepted as the industry standard, replacing the laminated type as toroidal transformers offer advantages in size, weight, and lower radiated field.