Polytronics Technology Corporation

Shau Chew Wang

Fu Hua Chu

Jyh Ming Yu

Yi Chun Chen

Kuo Chang Lo

Kuo Hsun Chen

A surface-mounted over-current protection device with positive temperature coefficient (PTC) behavior is disclosed. The surface-mounted over-current protection device comprises a first metal foil, a second metal foil corresponding to the first metal foil, a PTC material layer stacked between the first metal foil and the second metal foil, a first metal electrode, a first metal conductor electrically connecting the first metal foil to the first metal electrode, a second metal electrode corresponding to the first metal electrode, a second metal conductor electrically connecting the second metal foil to the second metal electrode, and at least one insulated layer to electrically insulate the first metal electrode from the second metal electrode. The surface-mounted over-current protection device, at 25&#xb0; C., indicates that a hold current thereof divided by the product of a covered area thereof and the number of the conductive composite module is at least 0.16 A/mm.

Surface-mounted over-current protection device

An LED apparatus with temperature self-regulating, over-temperature protection, and over-current protection function comprises an LED chip, a heat dissipation plate, a heat conductive layer and a temperature control device. The heat dissipation and the heat conductive layer disposed thereon carry the LED chip and dissipate the heat generated from the LED chip that is connected to an electric power source for luminance. The temperature control device exhibiting PTC behavior is electrically connected between the LED chip and the electric power source in series, and the distance between the LED chip and the temperature control device is less than 3 cm. The heat conductive layer can consist of polymeric dielectric material and has a heat conduction coefficient larger than 1.0 W/mK at 25&#xb0; C.

LED apparatus with temperature control function

A high voltage over-current protection device includes a positive temperature coefficient (PTC) electrically conductive heat-dissipation layer and two metal electrodes. The PTC electrically conductive heat-dissipation layer includes at least one polymer, an electrically conductive filler, and a heat conductive filler. Due to the high thermal conductivity of the heat conductive filler (with a coefficient of thermal conductivity higher than 1 W/mK), the high voltage over-current protection device has a high thermal conduction characteristic, and the withstand voltage thereof can be substantially uniformly distributed in the PTC electrically conductive heat-dissipation layer to enhance its high voltage withstanding characteristic.

High voltage over-current protection device

An over-current protection device comprises two metal foils and a positive temperature coefficient (PTC) material layer. The PTC material layer is sandwiched between the two metal foils and comprises plural crystalline polymers with at least one polymer melting point below 115&#xb0; C., and a non-oxide electrically conductive ceramic powder. The non-oxide electrically conductive ceramic powder exhibits a certain particle size distribution. The PTC material layer has a resistivity below 0.1 &#x3a9;-cm. The initial resistance of the device is below 20 m&#x3a9;, and the area of the PTC material layer is below 30 mm. The over-current protection device exhibits a surface temperature below 100&#xb0; C. under the trip state of over-current protection.

Over-current protection device

An axial leaded over-current protection device comprised of a plurality of PTC devices, a first terminal metal strip, and a second terminal metal strip. One end of the first terminal metal strip diverges into a plurality of electrode strips, and the plurality electrode strips are connected to an electrode layer of each PTC device. The second terminal metal strip is connected to the other electrode layer of each PTC device, i.e., the one not being connected to the first terminal metal strip. Accordingly, the first terminal metal strip and second terminal metal strip are respectively connected to the two electrode layers of each PTC device and become in parallel thereby, so that the resistance of the over-current protection device can be decreased.

Growing community of inventors

Taipei, Taiwan

Shau Chew Wang