An electronic component includes a temperature sensor including a pair of electrodes, at least one metal block electrically connected to an electrode of the temperature sensor, an insulation portion in which the temperature sensor and the at least one metal block are embedded, and an external terminal electrically connected to the electrode of the temperature sensor. The at least one metal block includes a flat surface exposed from the insulation portion. The flat surface defines the external terminal.

A PTC circuit protection device, includes: two PTC units, each of the PTC units including a first insulating layer, a first electrically conductive layer, a PTC polymeric layer, a second electrically conductive layer, a second insulating layer, a first electrode, a second electrode; an insulating bridge layer interconnecting the first insulating layers of the PTC units; and first and second gaps formed between the PTC units and located at two opposite sides of the insulating bridge layer.

A temperature sensor element has such a structure as, when reinforcing lead wires on internal electrodes with a paste, one side surface of each of the lead wires is covered with a reinforcement paste and the other side surface is not covered with the reinforcement paste without covering the entire lead wires welded and connected to the internal electrodes. This allows elimination of cause of cracks generating, thereby securing sufficient joining strength and reinforcement of conductivity of the internal electrodes and the lead wires, and securing connection strength between the lead wires and the internal electrodes.

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 fluorine-containing copolymer, and its melting point ranges from 210? C. to 240? C. The conductive filler consists of carbon black solely, and is used to form an electrically conductive path in the heat-sensitive layer. In addition, the over-current protection device has a resistance-jump ratio ranging from 1.2 to 1.3 between 40? C. and 130? C.

The present invention relates to a protective element which comprises a layered PTC element having a first main surface and a second main surface, a first electrode that is positioned on the first main surface of the PTC element and a second electrode that is positioned on the second main surface of the PTC element, and the protective element characterized in that at least a portion of the first electrode and at least a portion of the second electrode are positioned so as to oppose each other with the PTC element being interposed therebetween, and a portion of the first main surface is exposed.

A surface mountable over-current protection device comprises a PTC material layer, first and second conductive layers, left and right electrodes, left and right conductive members, and left and right insulating members. The PTC material layer comprises a left notch at a left end and a right notch at a right end. The first conductive layer comprises a primary portion disposed on an upper surface of the PTC material layer and a secondary portion extending over the left notch, and the second conductive layer comprises a primary portion disposed on a lower surface of the PTC material layer and a secondary portion extending over the underside of the right notch. The left conductive member connects to the left electrode and the first conductive layer and isolates from the second conductive layer. The right conductive member connects to the right electrode and the second conductive layer and isolates from the first conductive layer. The left and right insulating members are disposed in the left and right notches, respectively. The PTC material layer is not in direct contact with the left and right conductive members, and the primary portion and the secondary portion of the first or second conductive layer have different thicknesses.

A hybrid circuit protection device includes a positive temperature coefficient (PTC) component, a voltage-dependent resistor, a gas discharge tube (GDT), and first and second conductive leads that are respectively connected to the PTC component and the GDT. The voltage-dependent resistor and the PTC component are electrically connected in series, the GDT is electrically connected to the voltage-dependent resistor and the PTC component, and the GDT has a breakdown voltage greater than a varistor voltage of the voltage-dependent resistor as determined at 1 mA.

A chip-type electronic component that includes: a ceramic body 20 having a volume V of 0.12 mm.sup.3 or less, wherein the ceramic body comprises: a perovskite compound containing Ti and Ba, and at least Si, and wherein an Si content in the ceramic body 20 satisfies: 0 mol %<[Si]0.62 mol %, where [Si] is the Si content (mol %) per 100 mol % of a total content of elements in the ceramic body excluding oxygen.

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 first fluoropolymer and a second fluoropolymer. The first fluoropolymer includes a first melting point, and the second fluoropolymer has a second melting point lower than the first melting point. The difference between the first melting point and the second melting point is smaller than 14 C. The second fluoropolymer has a second melt flow index ranging from 0.4 g/10 min to 0.7 g/10 min.

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 first fluoropolymer and a second fluoropolymer. The first fluoropolymer has a first volume and a first melt flow index, and the second fluoropolymer has a second volume and a second melt flow index. The second melt flow index ranges from 0.4 g/10 min to 0.7 g/10 min and is lower than the first melt flow index, and a volume ratio by dividing the second volume by the first volume ranges from 0.4 to 0.6.