Whether you know the specifications of the flyback transformer you need or not, Competitive Magnetics can help you. We can design the flyback transformer that best applies to your needs, or we can build the custom flyback transformer that you need. We can provide you with a free sample, contact us for details.

A simple and low cost power supply is quite popular. The single ended flyback circuit topology fits this description. The flyback transformer utilizes the "flyback" action of an inductor or flyback transformer to convert the input voltage and current to the desired output voltage and current. Modern flyback transformer and circuit design now permit use in excess of 300 watts of power, but most applications are less than 50 watts.

By definition a transformer directly couples energy from one winding to another winding. A flyback transformer does not act as a true transformer. A flyback transformer first stores energy received from the input power supply (charging portion of a cycle) and then transfers energy (discharge portion of a cycle) to the output, usually a storage capacitor with a load connected across its terminals. An application in which a complete discharge is followed by a short period of inactivity (known as idle time) is defined to be operating in a discontinuous mode. An application in which a partial discharge is followed by charging is defined to be operating in the continuous mode.

Gapped cores increase the magnetizing force needed to reach saturation and lower the inductance of the flyback transformer (or inductor). Consequently, a gapped flyback transformer (or inductor) can handle higher peak current values, and thereby storing more energy, most of which is stored in the magnetic field of the gap. For these reasons almost all flyback transformers (or inductors) are gapped. The gap may be a discrete physical gap, several smaller discrete physical gaps or a distributed gap. Distributed gaps are inherently present in low permeability powdered cores. The bulk of the stored energy is stored in the magnetic field of the gap(s).
 

Most modern flyback transformers are operated at high frequency therefore gapped ferrite core materials are typically used.

Competitive Magnetics manufactures flyback transformers in a wide variety of shapes and sizes. This includes; various standard types of “core with bobbin” structures (E, EP, EFD, EC, ETD, PQ, POT, U and others), toroids, and some custom designs. We have experience with foil windings, litz wire windings, and perfect layering. For toroids, special winding techniques such as sector winding, progressive winding, bank winding, and progressive bank winding can be accomplished to satisfy your dielectric, creepage distance, capacitance, and leakage inductance requirements.