Oki Electric Industry Co., Ltd.

Fuji Jukogyo Kabushiki Kaisha

Nippon Telegraph and Telephone Public Corporation

Haruo Mori

Kotaro Kato

Jun Ueda

Kazuo Hagimura

Hiroshi Tanabe

Hideaki Okayama

Yasuo Ohno

Masahisa Nemoto

Yutaka Ohta

Akinori Tsukuda

Hirokazu Tsukada

Tadashige Ueda

Isamu Endo

Takayuki Kakinuma

K&times;K optical switch unit according to the present invention is comprised of input ports - - , 1&times;M optical matrix switches - - - - connected with the input ports - - , N&times;N optical matrix switches - - - - , and - - - - connected with the 1&times;M optical matrix switches - - - - , an M&times;1 optical matrix switches - - - - connected with the N&times;N optical matrix switches - - - - , and - - - - , and output ports - - connected with the M&times;1 optical matrix switches - - - - , where K&equals;M&times;N, M and N are integers more than 1.

Optical switch unit

A differential amplifying circuit includes a differential input portion, a load portion, a switching portion, and a constant current source. The differential input portion is connected to the constant current source, and includes a pair of field effect transistors (FETs), with one having a gate for receiving an input voltage, a source connected to the current source and a drain connected to a first node, and the other having a gate for receiving a reference voltage, a source connected to the current source and a drain connected to a second node. The load portion includes a pair of FETs, with one having a drain connected to a first power source and a source connected to a first output terminal, and the other having a drain connected to the first power source and a source connected to a second output terminal. The switching portion includes a pair of FETs, with one having a source connected to the first output terminal, and the other having a source connected to the second output terminal. The pair of FETs of the load portion respond to the potentials of the first and second nodes, respectively, so that the switching portion can perform a high speed switching operation.

Differential amplifying circuit operable at high speed

The semiconductor device comprises a semiconductor substrate, a plurality of spaced active elements, for example, of a planer type formed on one surface of the substrate, and a supporting plate bonded to the opposite surface of the substrate. A groove is cut through the substrate to reach the supporting plate for isolating the active elements.

High voltage integrated semiconductor devices using a thermoplastic

A PNPN semiconductor switch including an N type semiconductor substrate, spaced apart first and second P type diffused regions formed on a surface of an N type substrate, spaced apart first and second N type diffused regions formed in the second P type diffused region, a first gate insulating layer formed on the surface of the second P type diffused region between the first and second N type diffused regions to cover portions thereof, a first gate electrode formed on the first gate insulating layer between the first and second N type diffused regions, a resistance region disposed on the first gate insulating layer, one end of the resistance region on the side opposite to the first gate electrode, a second gate insulating layer overlying the first gate electrode and the resistance region, a semiinsulating layer formed on the surface of the substrate except over the first and second P type diffused regions, an insulating layer overlying the semiinsulating layer, a P gate electrode electrically connected to the second P type diffused region and the second N type diffused region, a second gate electrode formed on the second gate insulating layer at a portion above the first gate electrode, a cathode electrode connected to the first N type diffused region, an anode electrode connected to the first P type diffused region and the second gate electrode and a high resistance region formed immediately beneath the first gate insulating layer and between the first and second N type diffused regions.

PNPN Light sensitive semiconductor switch with phototransistor connected

A circuit for preventing a dV/dt erroneous operation of a PNPN semiconductor switch is replaced by a capacitance on the surface of a semiconductor substrate, a high resistance gate electrode. In other words, such a circuit is formed on the surface of the substrate by a slight modification of the basic design without decreasing the chip area and without isolating component elements.

PNPN Semiconductor switches

Air bleeding apparatus for an exhaust emission control system comprising three plates joined face to face. The first plate has a plurality of grooves each communicating at one end with a vacuum source and at the other end with a vacuum actuator for an ignition timing control system or an exhaust gas recirculation control valve. The second plate has a plurality of orifices communicating with the grooves, respectively; the third end plate has a vent hole therethrough and grooves diverging from the vent hole and respectively communicating with the orifices. The second plate is joined abuttingly to and between the first and third plates whereby the grooves form conduits therewith, whereby the conduits of the first plate communicate with the vent hole of the third plate through the respective orifices of the second plate and the respective conduits of the third plate. The characteristics of the apparatus may be varied by changing the second plate to one having different orifices.

Internal combustion engine having exhaust emission control system

An exhaust gas purification system for internal combustion engines having at least two cylinders of which the port of each exhaust valve communicates with a port passage provided in the cylinder head, and a pair of the adjacent port passages communicate with a common port passage forming a siamese port passage therewith. A secondary air intake passage having a check valve communicates with the port passages for introducing secondary air by exhaust pulsation. In order to enhance the exhaust pulsation effect, the exhaust pipe connected to the opening of the common port passage has a constant cross section of a fixed diameter. Heat insulation is provided along the siamese port passage and a portion of the exhaust pipe for good oxidation of the unburned constituents. The total volume of the exhaust passage through the siamese port passage and the heat insulated exhaust pipe portion is equal to the displacement volume of the corresponding cylinders for introduction of a sufficient amount of the secondary air. The ignition timing is retarded to restrict the combustion temperature to under 2000.degree. C. for reducing the amount of nitrogen oxides.

Internal combustion gasoline engine

The characteristics of an exhaust emission control system can be varied by bleeding air into a vacuum conduit through which a vacuum is applied to a vacuum actuator in the exhaust emission control system. Means for bleeding air into the vacuum conduit includes at least one replaceable orifice. Another ambient air bleeding means comprises three plates which are joined face to face to one after another to form internal fluid connections between pressure and vacuum conduits through which intake passageway vacuum is applied to a vacuum actuator in an exhaust emission control system. One of the three plates is formed with a plurality of air bleed control orifices and can be easily replaced with another one.

Growing community of inventors

Tokyo, Japan

Haruo Mori