A frequency-dependent resistance element includes an element assembly composed of a sintered magnetic material and a coil conductor embedded in the element assembly. The sintered magnetic material is composed of a primary component containing Fe, Zn, Ni, and Cu and a secondary component containing Co. In the primary component, on a percent by mole basis, the Fe content is 46.79 to 47.69, the Zn content is 12.60 to 24.84, and the Ni content is 19.21 to 32.36 in terms of Fe.sub.2O.sub.3, ZnO, and NiO, respectively. The molar ratio (Ni:Zn) of Ni to Zn is (1X):X, where X is from about 0.28 to about 0.56. The content of Co in terms of Co.sub.3O.sub.4 is 1.0 to 10.0 parts by mass relative to 100 parts by mass of the primary component containing Fe, Zn, Ni, and Cu in terms of Fe.sub.2O.sub.3, ZnO, NiO, and CuO, respectively.

A process for producing a multilayer varistor (MLV) if remained its size unchanged as prior arts is favorable to outstandingly increase overall current-carrying area and improve the performance of final produced MLV; and the MLV has laminated a lower cap, an inner-electrode stack formed from piling up several inner-electrode gaps (g), and an upper cap into a unity, and at least satisfies the condition that the lower cap and the upper cap has a thickness smaller than a thickness of the inner-electrode gap (g), but equal to or greater than 0.1 times of the thickness of the inner-electrode gap (g).

A process for producing a multilayer varistor (MLV) if remained its size unchanged as prior arts is favorable to outstandingly increase overall current-carrying area and improve the performance of final produced MLV; and the MLV has laminated a lower cap, an inner-electrode stack formed from piling up several inner-electrode gaps (g), and an upper cap into a unity, and at least satisfies the condition that the lower cap and the upper cap has a thickness smaller than a thickness of the inner-electrode gap (g), but equal to or greater than 0.1 times of the thickness of the inner-electrode gap (g).

An electrostatic discharge circuit may include a substrate, an N+ buried layer in the substrate, an n-type epitaxial layer on the N+ buried layer and the substrate, a first P region in an anode region of the n-type epitaxial layer, a first N+ region in the first P region, an N-well in a cathode region of the n-type epitaxial layer, a first P+ region in the N-well, and a second N+ region located in the N-well. The first N+ region may be located closer to the second N+ region than the first P+ region.

In one embodiment a varistor may include a ceramic body. The varistor may further comprise a multilayer coating disposed around the ceramic body. The multilayer coating may include an outer layer comprising an epoxy material. The multilayer coating may also include an inner layer that is adjacent the ceramic body and is disposed between the outer layer and the ceramic body. The inner layer may comprise a polymeric material that is composed of an acrylic component.

A method of manufacturing a metal oxide varistor (MOV), the method including placing a quantity of a MOV composition in a pressing die, the MOV composition including metal oxide granules mixed with a polyaniline-polymer, performing a pressing operation including operating the pressing die to compress the MOV composition into a solid MOV chip, and applying first and second electrodes to opposing first and second sides of the MOV chip, wherein the pressing operation is performed at a temperature in a range of 15 degrees Celsius to 200 degrees Celsius.