OXIDE MAGNETIC MATERIAL AND SWITCHING POWER SUPPLY EMPLOYING THE SAME

摘要

PURPOSE: To obtain a magnetic material exhibiting low magnetic loss in high frequency band and a small-sized, high efficiency, low heat generation switching power supply employing it. CONSTITUTION: A perminvar type oxide magnetic material principally comprises 55mol.% or more of Fe2 O3 or 53mol.% or more of Fe2 O3 and specified quantity of CoO, as a subconstituent. It is admixed with at least CaO and SiO2 to produce an MnZn ferrite containing metal ions exhibiting magnetic anisotropy. The magnetic material thus produced is employed in the core for main transformer. Magnetic loss can be reduced in a switching power supply when it is driven with flux density of 150mT or less at a switching frequency of 500kHz to 5MHz.