A chip-type fuse has a substrate. Two pads are disposed over a first side of the substrate. At least one fusible element is disposed over the first side of the substrate and electrically connects to the pads. A protective layer covers the first side of the substrate and the fusible element. The fusible element has a cross-section that is substantially circular, so the time durations for heat conduction from the center to points on the radial edge at the cross-section of the fusible element are almost equal. Thus, the fusible element can be uniformly heated. Therefore, when the circuit is overheated, the blow of the fusible element is uniform, which may effectively interrupt the circuit and protect the circuit.

A fuse including a fuse body, a fusible element disposed within the fuse body providing an electrically conductive pathway extending between a first end of the fuse body and a second end of the fuse body, and a heat shield disposed within the fuse body intermediate an interior surface of the fuse body and an exterior surface of the fuse body for mitigating heat flow therebetween.

A fuse device includes a fuse element and a cooling member, wherein the fuse element includes a low thermal conductivity portion having a relatively low thermal conductivity in which an interrupting portion that is blown out by heat is separated from the cooling member, and a high thermal conductivity portion having a relatively high thermal conductivity, provided in a portion other than the interrupting portion, and in contact with or close to the cooling member.

A fuse device includes a fuse element and a cooling member, wherein the fuse element includes a low thermal conductivity portion having a relatively low thermal conductivity in which an interrupting portion that is blown out by heat is separated from the cooling member, and a high thermal conductivity portion having a relatively high thermal conductivity, provided in a portion other than the interrupting portion, and in contact with or close to the cooling member.