Abstract: A surface mountable over-current protection device comprises one PTC material layer, first and second conductive layers, first and second electrodes, and an insulating layer. The PTC material layer comprises crystalline polymer and conductive filler dispersed therein. The first and second conductive layers are disposed on first and second planar surfaces of the PTC material layer, respectively. The first and second electrodes are electrically connected to the first and second conductive layers. The insulating layer is disposed between the first and the second electrodes for insulation. At the melting point of the crystalline polymer, the CTE of the crystalline polymer is greater than 100 times the CTE of the first or second conductive layer, and the first and/or second conductive layers has a thickness which is large enough to obtain a resistance jump value R3/Ri less than 1.4.

Abstract: A surface mountable over-current protection device having upper and lower surfaces comprises a PTC device, first and second electrodes, and first and second circuits. The PTC device comprises a PTC material layer and first and second conductive layers. The PTC material layer is disposed between the conductive layers and comprises crystalline polymer and conductive filler dispersed therein. The first electrode comprises a pair of first metal foils, whereas the second electrode comprises a pair of second metal foils. The first circuit connects the first electrode and conductive layer, and has a first planar line extending horizontally. The second circuit connects the second electrode and conductive layer, and has a second planar line extending horizontally. At least one of the planar lines has a thermal resistance sufficient to mitigate heat dissipation by which the over-current protection device undergoes a test at 25° C. and 8 amperes can trip within 60 seconds.

Abstract: A surface-mountable over-current protection device comprises one PTC material layer, first and second connecting conductors, first and second electrodes and an insulating layer. The PTC material layer has a resistivity less than 0.2 ?-cm, and comprises crystalline polymer and conductive filler dispersed therein. The first and second connecting conductors are capable of effectively dissipating heat generated from the PTC material layer. The first and second electrodes are electrically connected to first and second surfaces of the PTC material layer through the first and second connecting conductors, respectively. The dissipation factor depending on the ratio of the total area of the electrodes and the conductors to the area of the PTC material layer is greater than 0.6. At 25° C., the value of the hold current of the device divided by the product of the area of the PTC material layer and the number of the PTC material layer is greater than 1A/mm2.

Abstract: An over-current protection device includes a first substrate, a second substrate, a first grating electrode, a second grating electrode and a positive temperature coefficient (PTC) material layer. The first grating electrode and the second grating electrode are formed on the first substrate and are interlaced and spaced on a same plane. The PTC material layer is formed on the first substrate, the first grating electrode and the second grating electrode, and between the first grating electrode and the second grating electrode. In an embodiment, the first grating electrode and the second grating electrode serve as a current input port and a current output port, respectively.

Abstract: An over-current protection device is disposed on a circuit board and configured to protect a battery. The over-current protection device includes a resistive device, at least one insulation layer and a weld electrode layer. The resistive device exhibits positive temperature coefficient behavior. The insulation layer has a thickness of at least 0.03 mm. The weld electrode layer is configured to weld a strip interconnect member to electrically coupled to the battery, and has a thickness of at least 0.03 mm. The insulation layer and the resistive device are disposed between the weld electrode layer and the circuit board. The circuit board, the resistive device and the weld electrode layer are electrically coupled in series. The association of the resistive device and the weld electrode layer has a thermal mass capable of withstanding welding the strip interconnect member without significant damage to the over-current protection device.

Abstract: A surface-mountable over-current protection device comprises a PTC material layer, first and second conductive layers, first and second electrodes, first and second electrically conductive connecting members. The PTC material layer has a resistivity less than 0.18 ?-cm. The conductive layers are in contact with opposite surfaces of the PTC material layer. The first electrode comprises a pair of first metal foils and is insulated from the second conductive layer. The second electrode comprises a pair of second metal foils and is insulated from the first conductive layer. The first electrically conductive connecting member connects to the first metal foils and conductive layer. The second electrically conductive connecting member connects to the second metal foils and conductive layer. The first electrically conductive connecting member comprises 40%-100% by area of the first lateral surface, and the second electrically conductive connecting member comprises 40%-100% by area of the second lateral surface.

Abstract: An over-current protection device comprises a PTC material layer, a first electrode layer and a second electrode layer. The PTC material layer has opposite first and second surfaces and opposite first and second lateral surfaces. The first electrode layer is in physical contact with the first surface of the PTC material layer and extends to the first lateral surface. The second electrode layer is in physical contact with the first surface of the PTC material layer and extends to the second lateral surface. The second electrode layer is insulated from the first electrode layer by a first separation. The first electrode layer and the second electrode layer are substantially laterally symmetrical, and serve as interfaces for current flowing in and out of the device when the over-current protection device is in use.

Abstract: A heat conductive dielectric polymer material comprises a polymer, a curing agent and a heat conductive filler. The polymer comprises a thermoplastic and a thermosetting epoxy resin. The thermoplastic comprises 3% to 30% by volume of the heat conductive dielectric polymer material, and the thermosetting epoxy is selected from end-epoxy-function group epoxy resin, side chain epoxy function group epoxy resin, multi-function group epoxy resin or the mixture thereof. The curing agent can cure the thermosetting epoxy resin at a temperature. The heat conductive filler is uniformly distributed in the polymer and comprises 40% to 70% by volume of the heat conductive dielectric polymer material. The heat conductive dielectric polymer material has an interpenetrating network structure, and the heat conductive coefficient is greater than 1.0 W/m-K.

Abstract: An over-current protection device is of an approximately quadrilateral structure with upper and lower surfaces, first and second side surfaces, in which the second side surface contains a bevel. The device comprises first and second electrodes, a first PTC material layer, and first and second conductive connecting members. The first electrode is formed on the upper or lower surface. The second electrode is formed on the lower surface and is insulated from the first electrode. The first PTC material layer extends along the upper surface and has a first surface electrically coupled to the first electrode, and a second surface electrically coupled to the second electrode. The first conductive connecting member is formed on the first side surface and is electrically coupled to the first electrode. The second conductive connecting member is formed on the second side surface and extends along the bevel to electrically couple to the second electrode.

Abstract: An over-current protection device comprises a resistance material with positive or negative temperature coefficient and an upper surface and a lower surface; a first electrode layer having a first groove, disposed on the upper surface; a first surface mount pad disposed on the upper surface; a second electrode layer disposed on the lower surface, electrically connecting to the first surface mount pad; a second surface mount pad disposed on the lower surface, electrically connecting to the first electrode layer; a second groove electrically separating the first surface mount pad from the first electrode layer; and a third groove electrically separating the second electrode layer from the second surface mount pad. The first groove divides the first electrode layer into two connected regions. The first and second surface mount pads are separated from each other and one end of the first groove connects to the second groove.

Abstract: An LED apparatus includes an LED component and a current-limiting device. The LED component includes at least one LED having a corresponding current-limiting resistance value. The current-limiting device includes a plurality of PTC devices connected in series. The plurality of PTC devices are capable of effectively sensing the temperature of the LED and are electrically coupled to the LED component. The resistance value of the current-limiting device increases with the increment of sensed temperature. The current-limiting device has a resistance close to or equal to the current-limiting resistance value at a temperature at which the LED operates normally. When the temperature of the LED gradually increases to an abnormal temperature, current allowable to be flowed through the current-limiting device gradually decreases to be lower than LED operating current.

Abstract: An over-current protection device includes two metal foils and a PTC material layer. The PTC material layer is laminated between the two metal foils and has a resistivity less than 0.4 ?-cm. The PTC material layer includes crystalline polymer and electrically conductive ceramic filler dispersed in the crystalline polymer. The conductive ceramic filler is of HCP structure and includes 70-95% by weight of the PTC material layer. The trip jump value of the over-current protection device after 300 times trip is less than or equal to 25. The resistance repeatability of the device can be effectively improved by adding the conductive ceramic filler.

Abstract: A thermistor includes a resistive device, a first insulation layer, a first electrode, a second electrode and a first heat-conductive layer. The resistive device includes a first electrically conductive member, a second electrically conductive member and a polymeric material layer laminated therebetween. The polymeric material layer exhibits positive temperature coefficient (PTC) or negative temperature coefficient (NTC) behavior. The first insulation layer is disposed on the first electrically conductive member. The first electrode is electrically coupled to the first electrically conductive member, whereas the second electrode is electrically coupled to the second electrically conductive member and is insulated from the first electrode. The first heat-conductive layer is disposed on the first insulation layer, and has a heat conductivity of at least 30 W/m-K and a thickness of 15-250 ?m.

Abstract: An over-current protection device includes two metal foils and a PTC material layer. The PTC material layer is laminated between the two metal foils and has a resistivity less than 0.4 ?-cm. The PTC material layer includes crystalline polymer and electrically conductive ceramic filler dispersed in the crystalline polymer. The conductive ceramic filler is of HCP structure and includes 70-95% by weight of the PTC material layer. The trip jump value of the over-current protection device after 300 times trip is less than or equal to 25. The resistance repeatability of the device can be effectively improved by adding the conductive ceramic filler.

Abstract: A thermistor includes a resistive device, a first insulation layer, a first electrode, a second electrode and a first heat-conductive layer. The resistive device includes a first electrically conductive member, a second electrically conductive member and a polymeric material layer laminated therebetween. The polymeric material layer exhibits positive temperature coefficient (PTC) or negative temperature coefficient (NTC) behavior. The first insulation layer is disposed on the first electrically conductive member. The first electrode is electrically coupled to the first electrically conductive member, whereas the second electrode is electrically coupled to the second electrically conductive member and is insulated from the first electrode. The first heat-conductive layer is disposed on the first insulation layer, and has a heat conductivity of at least 30 W/m-K and a thickness of 15-250 ?m.

Abstract: A surface mountable thermistor comprises a resistive device, first and second electrodes, and at least one heat conductive dielectric layer. The resistive device contains first and second electrically conductive members and a polymeric material layer laminated therebetween. The polymeric material layer exhibits PTC or NTC behavior. The polymeric material layer and the first and second electrically conductive members commonly extend in a first direction. The first electrode is electrically coupled to the first electrically conductive member. The second electrode is electrically coupled to the second electrically conductive member and is insulated from the first electrode. The heat conductivity of the first electrode or the second electrode is at least 50 W/mK. The heat conductive dielectric layer comprises polymeric insulation matrix and heat conductive filler, and is disposed between the first electrode and the second electrode. The heat conductivity of heat conductive dielectric layer is between 1.

Abstract: An over-current protection device is disposed on a circuit board and configured to protect a battery. The over-current protection device includes a resistive device, at least one insulation layer and a weld electrode layer. The resistive device exhibits positive temperature coefficient behavior. The insulation layer has a thickness of at least 0.03 mm. The weld electrode layer is configured to weld a strip interconnect member to electrically coupled to the battery, and has a thickness of at least 0.03 mm. The insulation layer and the resistive device are disposed between the weld electrode layer and the circuit board. The circuit board, the resistive device and the weld electrode layer are electrically coupled in series. The association of the resistive device and the weld electrode layer has a thermal mass capable of withstanding welding the strip interconnect member without significant damage to the over-current protection device.

Abstract: An over-current protection device includes a resistive device, an insulation layer, an electrode layer and at least one electrically conductive connecting member. The resistive device includes a first electrode foil, a second electrode foil and a positive temperature coefficient (PTC) material layer laminated between the electrode foils. The insulation layer is formed on the surface of the first electrode foil, and the electrode layer is formed on the surface of the insulation layer. The conductive connecting member penetrates the electrode layer, the insulation layer and the first electrode foil for electrically connecting the electrode layer and the first electrode foil. The conductive connecting member is insulated from the second electrode foil. One of the first and second electrode foils is configured to electrically connect to a protective circuit module (PCM), and the other one is configured to electrically connect to an electrode terminal of a battery to be protected.

Abstract: An over-current protection device comprises a PTC material layer, first and second conductive layers, first and second electrodes, and four conductive vias. The first and second conductive layers are in physical contact with first and second surfaces of the PTC material layer, respectively. The first electrode contains a pair of first metal foils, and the second electrode contains a pair of second metal foils. The four conductive vias are formed at the corners each defined by two adjacent planar lateral surfaces. Two conductive vias connect the pair of the first metal foils and the first conductive layer, and the other two conductive vias connect the pair of the second metal foils and the second conductive layer. The ratio of the sum of the cross-sectional areas of the conductive vias to a form factor area of the device is in the range of 7% to 20%.

Abstract: An over-current protection device includes a first conductive member, a second conductive member, a resistive device and a temperature sensing switch. The first conductive member includes a first electrode foil and a second electrode foil those are formed on a same plane. The resistive device is laminated between the first conductive member and the second conductive member and exhibits positive temperature coefficient or negative temperature coefficient behavior. The temperature sensing switch can switch the first electrode foil and the second electrode foil between electrically conductive status and current-restriction status, e.g., open circuit, according to temperature variation. The threshold temperature of the temperature sensing switch is lower than the trip temperature of the resistive device.