A method of making a PTC protection chip device includes: preparing an assembly of a PTC polymer material, a spacer unit, and first and second electrode sheets of a metal-plated copper foil, the PTC polymer material and the spacer unit of the assembly being sandwiched between and cooperating with the first and second electrode sheets to form a stack; subjecting the stack to a hot pressing process, so that the first and second electrode sheets contact and are pressed against the PTC polymer material and the spacer unit and so that the PTC polymer material is bonded to and cooperates with the first and second electrode sheets to form a PTC laminate; and cutting the PTC laminate so as to form the PTC circuit protection chip device.

A method of making a PTC protection chip device includes: preparing an assembly of a PTC polymer material, a spacer unit, and first and second electrode sheets of a metal-plated copper foil, the PTC polymer material and the spacer unit of the assembly being sandwiched between and cooperating with the first and second electrode sheets to form a stack; subjecting the stack to a hot pressing process, so that the first and second electrode sheets contact and are pressed against the PTC polymer material and the spacer unit and so that the PTC polymer material is bonded to and cooperates with the first and second electrode sheets to form a PTC laminate; and cutting the PTC laminate so as to form the PTC circuit protection chip device.

A composite circuit protection device includes a positive temperature coefficient (PTC) component, first and second conductive leads, a solder and a diode component that is connected to the PTC component through the solder. The solder includes a first alloy material having a first melting point, and a second alloy material having a second melting point that is lower than the first melting point. Each of the first and second melting points is independently greater than 190 C. and lower than 308 C. The first and second conductive leads are respectively bonded to the PTC component and the diode component.

An over-current protection device includes an electrode layer and a heat-sensitive layer. The heat-sensitive layer exhibits a positive temperature coefficient (PTC) characteristic, and is laminated between a top metal layer and a bottom metal layer of the electrode layer. The heat-sensitive layer includes a polymer matrix and a conductive filler. The polymer matrix includes a fluoropolymer. The fluoropolymer has a plurality of spherulites, and the fractal dimension of each spherulite is lower than 12.

A PTC over-current protection device includes a first PTC component, a second PTC component, a first insulation layer, a first conductive via, and a second conductive via. The first PTC component includes a first electrode, a second electrode, and a first PTC element sandwiched between the first electrode and the second electrode. The second PTC component includes a third electrode, a fourth electrode, and a second PTC element sandwiched between the third electrode and the fourth electrode. The first insulation layer is disposed between the first PTC component and the second PTC component. The first conductive via electrically connects the first electrode and the third electrode, and the second conductive via electrically connects the second electrode and the fourth electrode.

A semiconductor ceramic composition including a compound represented by the following general formula (1) as a main component.

(Ba.sub.vBi.sub.xA.sub.yRE.sub.w).sub.m(Ti.sub.uTM.sub.z)O.sub.3 (1)

(wherein, A represents both elements of Na and K; RE is at least one element selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Gd, Dy and Er; and TM is at least one element selected from the group consisting of V, Nb and Ta.)

0.01x0.15 (2)

xy0.3 (3)

0(w+z)0.01 (4)

v+x+y+w=1 (5)

u+z=1 (6)

0.950m1.050 (7)

further, 0.001 mol to 0.055 mol of Ca is included and the ratio of Na/(Na+K) is 0.1 or more and less than 1.

The present disclosure provides a self-regulating electric heating film, including: an insulating isolation layer, an interdigital electrode arranged on the surface of the insulating isolation layer, a positive temperature coefficient coating covering the surface of a secondary electrode of the interdigital electrode, and an insulating protective layer covering the surface of a primary electrode of the interdigital electrode, wherein the positive temperature coefficient coating is not in contact with the primary electrode of the interdigital electrode, and the insulating protective layer overlaps the positive temperature coefficient coating.

Surface-mountable devices include a conductive polymer layer between first and second electrodes, on which are disposed first and second insulation layers, respectively, with first and second planar terminals on the second insulation layer. A first cross-conductor connects the second electrode to the first terminal, and is separated from the first electrode by a portion of the first insulation layer. A second cross-conductor connects the first electrode to the second terminal, and is separated from the second electrode by a portion of the second insulation layer. At least one cross-conductor may include a beveled portion through the first insulation layer. Alternatively, at least one cross-conductor may contact an anchor pad on the first insulation layer, the anchor pad having a small area relative to the areas of the terminals. Enhanced adhesion between the cross-conductor(s) and the first insulation layer is provided, while allowing thermal expansion without excessive stress.

Approaches provided herein include a protection device assembly including multilayer electrodes. In some embodiments, a protection device assembly may include a protection component, a first electrode layer extending along a first main side of the protection component, and a second electrode layer extending along a second main side of the protection component. The protection device assembly may further include a first substrate layer disposed over at least one of: the first electrode layer, and the second electrode layer, a foil layer disposed over the first substrate layer, wherein the foil layer is partially separated from the first electrode layer by the first substrate layer, and a solder pad extending around an end of the protection component and the first substrate layer, wherein the solder pad is in contact with the foil layer.

A positive temperature coefficient (PTC) circuit protection device including a dielectric substrate layer, first and second high resistance layers disposed on a top surface of the substrate layer in a spaced apart relationship to define a gap therebetween, a PTC layer disposed on the top surface of the substrate layer in the gap and in contact with the first and second high resistance layers, a mask layer covering a top surface of the PTC layer and portions of top surfaces of the first and second high resistance layers, an electrically conductive first terminal covering a first longitudinal end of the substrate layer and an outermost end of the first high resistance layer distal from the PTC layer, and an electrically conductive second terminal covering a second longitudinal end of the substrate layer and an outermost end of the second high resistance layer distal from the PTC layer.