Patent ID: 6989719
Filing Date: 2006-01-24
Classification: H01P

Abstract:
1. A non-reciprocal circuit element, comprising: a magnetic plate; a common electrode disposed at a first face of the magnetic plate; a first main segment; a second main segment; a third main segment; the three main segments extending from a periphery of the common electrode in three directions so as to surround the magnetic plate, the three main segments being folded to a second face of the magnetic plate and intersecting on the second face with predetermined angles, and a magnet for applying a bias magnetic field, the magnet opposing the magnetic plate, wherein a temperature coefficient of a saturation magnetization of the magnetic plate is from −0.2%/° C. to −0.1%/° C. in a temperature range from −35° C. to 85° C.; a temperature coefficient of a residual magnetization of the magnet is from −0.20%/° C. to −0.15%/° C. in a temperature range from −35° C. to 85° C.; and, the magnetic plate comprises garnet ferrite represented by the formula; wherein R is at least one element selected from the group consisting of La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, M is In or a combination of Ca and Sn or a combination of Ca and Zr, and subscripts x, y, and z representing a stoichiometric ratio satisfy 0.3≦x≦1.5, 0≦y≦0.6, and 0≦z≦0.5.