Back to results
US 5,846,448 AGranted
Ferrite and ferrite core for power supply
AssigneeTDK Corporation
InventorsKatsushi Yasuhara, Takashi Ito, Osamu Takeda, Shoji Inoue
Life of this patent
Estimating the term…
Abstract
A ferrite having low power losses, high .DELTA.B=Bm-Br at high frequency, and improved .mu.a-B properties is provided as well as a core for a power supply using the same. The ferrite contains 30-41 mol % of MnO, 6-16 mol % of ZnO, and the balance of Fe.sub.2 O.sub.3 as main components and 50-250 ppm of SiO.sub.2, 200-1500 ppm of CaO, up to 4000 ppm of SnO.sub.2, up to 3000 ppm of TiO.sub.2, at least 300 ppm of SnO.sub.2 +TiO.sub.2, from more than 0 to 500 ppm of Nb.sub.2 O.sub.5, and from more than 0 to 400 ppm of ZrO.sub.2 as subordinate components.
Claims10
A ferrite characterized by comprising
- manganese oxide, zinc oxide, and iron oxide as main components, and
- silicon oxide, calcium oxide, tin oxide and/or titanium oxide, niobium oxide, and zirconium oxide as subordinate components, wherein
- in the main components, the content of manganese oxide is 30 to 41 mol % calculated as MnO and the content of zinc oxide is 6 to 16 mol % calculated as ZnO, and
- the weight proportion of the subordinate components based on the main components is such that
- silicon oxide is 50 to 250 ppm calculated as SiO.sub.2,
- calcium oxide is 200 to 1,500 ppm calculated as CaO,
- tin oxide is up to 4,000 ppm calculated as SnO.sub.2, titanium oxide is up to 3,000 ppm
- calculated as TiO.sub.2, and the total of tin oxide and titanium oxide is at least 300 ppm,
- niobium oxide is from more than 0 to 550 ppm calculated as Nb.sub.2 O.sub.5, and
- zirconium oxide is from more than 0 to 400 ppm calculated as ZrO.sub.2,
- P is present in a weight ratio of 5 to 35 ppm based on the main component, and
- the remainder iron oxide.
9 more elements
Dependencies are inferred from the claim text.