Littelfuse, Inc.

Littlefuse, Inc.

James A Colby

Edwin James Harris

Timothy E Pachla

Tushar Vyas

Stephen Whitnery

Du Yaosheng

A circuit protection device includes a fuse element placed in parallel with a PTC thermistor layer. The element and PTC thermistor layer are provided on one or more insulating substrate, such as an FR-4 or polyimide substrate. First and second conductors connect the fuse element and PTC thermistor layer electrically in parallel, such that current (i) initially under normal flows mainly through the fuse element and PTC thermistor layer at a lower drop in voltage and (ii) after an opening of the fuse element flows under normal operation through the PTC thermistor layer at a higher drop in voltage.

Integrated thermistor and metallic element device and method

A voltage variable material ('VVM') including an insulative binder that is formulated to intrinsically adhere to conductive and non-conductive surfaces is provided. The binder and thus the VVM is self-curable and applicable in a spreadable form that dries before use. The binder eliminates the need to place the VVM in a separate device or to provide separate printed circuit board pads on which to electrically connect the VVM. The binder and thus the VVM can be directly applied to many different types of substrates, such as a rigid FR-4 laminate, a polyimide, a polymer or a multilayer PCB via a process such as screen or stencil printing. In one embodiment, the VVM includes two types of conductive particles, one with a core and one without a core. The VVM can also have core-shell type semiconductive particles.

Direct application voltage variable material, devices employing same and methods of manufacturing such devices

The present invention provides an ESD apparatus that includes an electrical overstress suppression device in series with a capacitor. The ESD apparatus is ideally suited for use with network communication devices, but any electronic device requiring overvoltage protection and isolation may employ the ESD apparatus of the present invention. In one embodiment, the ESD apparatus includes a capacitor and an electrical overstress protection device that electrically communicates in series with the capacitor. In another embodiment, the ESD apparatus includes an electrical overstress protection device having a voltage variable material and a capacitor that electrically communicates in series with the overstress protection device. The capacitor is sized so that the overstress device can withstand an application of a predetermined steady state voltage.

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Lombard, IL, United States of America

James A Colby