Oki Electric Industry Co., Ltd.

Hiroyasu Torazawa

Hiroaki Ogawa

Kenji Mizuuchi

Kazuo Hagimura

A photocoupler ( ) includes a light emitting unit ( ) which emits an input light (P); a first path ( ) connecting a first terminal ( ) and a second terminal ( ); a switching circuit ( ) provided in the first path ( ) to open and close the first path ( ) in response to the input light (P); and a circuit breaker ( ) provided in the first path ( ) to disconnect the first path ( ) in response to over current (excess current).

Photocoupler and connecting system using the same

An optical coupling semiconductor switching circuit to be coupled to a light emitting device for controlling electric circuits. The switching circuit includes a light detector generating voltage in response to light from the light emitting device and an impedance circuit having a first and a second output terminal. The impedance circuit is connected to the light detector and passes through a voltage input from the light detector to the output terminals with little loss. A plurality of switching devices are connected in parallel between the output. Each switching device includes at least a pair of transistors each having a gate connected to the first output terminal, and an optical rectifier that is activated by light from the light emitting device. The rectifier has a cathode connected to a source of each transistor and a anode connected to the second input terminal.

Optical coupling semiconductor switching circuit

A photosensitive semiconductor device includes a photocoupler sealed within a sealing body which is composed of a light-transmissive resin material. An outer surface of the sealing body is carbonized to block external light and thus minimized the adverse effects of noise.

Photosensitive device having light transmissive sealing resin with carbonized outer surface

The present invention provides a photosensitive semiconductor device comprising a sealing body composed of a resin material for sealing photosensitive semiconductor elemental devices, a inside of the sealing body having a light-transmissive property, a surface of the sealing body composed of the resin material containing carbon. Owing to the above-described construction, the present invention can provide a photosensitive semiconductor device which eliminates the need for a mold resin forming process for forming only a lightproof film and is capable of simplifying a manufacturing process thereof and being rendered compact in size.

Method of manufacturing photosensitive semiconductor device

A photosemiconductor relay of the present invention comprises a light-emitting unit for emitting light therefrom, a light-receiving control circuit for providing a predetermined potential difference or more between a first connecting terminal and a second connecting terminal during a light-receiving period and electrically connecting the first and second connecting terminals to each other in response to the non-reception of the light, and a switching circuit for electrically connecting a first output terminal and a second output terminal to each other in response to the reception of the predetermined potential difference or more and restricting a load current flowing between the first and second output terminals to a predetermined value or less. Thus, since a current of a predetermined value or more does not flow into a load circuit connected between the output terminals, the load circuit is prevented from malfunctioning and the switching circuit is promptly turned off.

Photosemiconductor relay, photosemiconductor relay device, controller

The present invention relates to a light-activated semiconductor device comprising light-emitting elements for emitting light respectively, light-receiving elements for producing driving voltages in response to the light respectively and output elements activated in response to the driving voltages respectively. The light-receiving elements are disposed on two planes opposed to each other. The output elements are disposed on their corresponding planes in opposing relationship.

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Tokyo, Japan

Hiroyasu Torazawa