Fujitsu Corporation

Nissan Motor Company Limited

Nippon Zeon Company, Ltd.

Osamu Kobayashi

Kunihiko Gotoh

Tachio Yuasa

Jun Hasegawa

Atsushi Matsuda

Masayoshi Sekiya

Yasuo Kataoka

Haruki Oikawa

Hideo Sato

Koji Ikeda

Hisao Suzuki

Hideki Maeda

Satoshi Kumano

Yoshiaki Shimizu

Akiyoshi Watanabe

Kunimitsu Kousaka

Hiroshi Naritomi

Masatsugu Kamimura

Toru Mizutani

Hideki Shutou

Akira Shimozono

Seiji Endo

Yoshiyasu Sutou

Toshiyuki Yada

Yuasa Tachio

Ikuo Nakamura

Tomoko Saruwatari

Kunihiko Gotch

Takashi Yoshitake

A network monitoring and controlling apparatus for monitoring and controlling a transmission network formed by a plurality of transmission apparatus includes: a path information storing unit for storing path information; a quality information periodic collection unit for periodically collecting quality information; a quality deterioration detecting unit for determining whether or not quality of the path is deteriorated; a path via point searching unit searching the path information storing unit and obtaining information on a path via points of the path deteriorated in quality; a path via point quality information collection unit for collecting quality information of channels corresponding to the path via points; and a quality deterioration point identifying unit for determining whether or not a deteriorated path via point is present.

Network monitoring and controlling apparatus

A lower electrode of a capacitor element and a wiring are formed in a wiring layer that is one layer below an uppermost wiring layer. Subsequently, after the formation of a capacitance insulating film, a TiN film is formed on the entire surface thereof, and then the TiN film is patterned, thereby forming an upper electrode of a capacitor element and a lead wiring for electrically connecting the upper electrode to a wiring of a third wiring layer. Furthermore, in the uppermost layer, a shield is formed covering the upper portion of the capacitor element.

Semiconductor device and method of manufacturing the same

A current mode A/D converter for reducing current consumption while enhancing resolution. The A/D converter includes a V/I conversion circuit for sampling and converting an input voltage to a current, an I/V conversion circuit for converting the current supplied from the V/I conversion circuit to a comparison voltage, a comparator for comparing the current based on the comparison voltage and a reference current, and an encoder for generating a digital output signal based on the output signal of the comparator.

A/D converter

According to a first aspect of the present invention, a plurality of PN junctions are formed at the surface of a semiconductor substrate under a belt-like conductive film having a spiral shape which constitutes an inductance device. An inverted bias voltage is applied to the PN junctions, and the surface of the substrate is completely depleted. Since the inverted bias voltage is applied to the PN junctions, even though the impurity density of the surface of the substrate is high and the adjacent PN junctions are separated to a degree, the extension of the depletion layers can be increased and complete depletion of the surface of the substrate can be achieved.

Inductance device formed on semiconductor substrate

An output circuit that prevents the flow of a leakage current from its output terminal to a power supply is able to accommodate voltage levels higher than the power supply voltage level. The output circuit includes a p-channel MOS transistor connected between the output terminal and a high potential power supply. A first switch circuit is connected between the transistor and the high potential power supply. The first switch circuit selectively connects and disconnects a back-gate of the transistor and the high potential power supply in response to an external signal applied to the output terminal.

Output circuit for electronic devices

An operational amplifier has a differential amplification section, an output section, a control signal generation unit, and a drive control unit. The output section has a first transistor of a first conductivity type and a second transistor of a second conductivity type that is opposite to the first conductivity type. The first and second transistors are connected in series between a first power source unit and a second power source unit, and the first transistor is driven according to an output of the differential amplification section. The control signal generation unit is used to detect a current flowing through the first transistor and generate a control signal in response to the detected current. The drive control unit is used to drive the second transistor in response to the control signal.

Operational amplifier having stable operations for a wide range of source voltage, and current detector circuit employing a small number of elements

According to a first aspect of the present invention, a plurality of PN junctions are formed at the surface of a semiconductor substrate under a belt-like conductive film having a spiral shape which constitutes an inductance device. A reverse bias voltage is applied to the PN junctions, and the surface of the substrate is completely depleted. Since the reverse bias voltage is applied to the PN junctions, even though the impurity density of the surface of the substrate is high and the adjacent PN junctions are separated to a degree, the extension of the depletion layers can be increased and complete depletion of the surface of the substrate can be achieved.

A transcurrent circuit in which a first current flows in an output-stage circuit based on a second current flowing in an input-stage circuit and a given current transform ratio of the first current to the second current. In the transcurrent circuit, at least one of the input-stage circuit and the output-stage circuit in the transcurrent circuit is constructed with a plurality of transistors. Further, all the transistors in both of the input-stage circuit and the output-stage circuit have the same gate length.

Transcurrent circuit and current-voltage transforming circuit using the

Operational amplifier having stable operations for a wide range of

A protection circuit includes a first protection circuit, which is coupled between a signal output terminal of an internal circuit and an external connection terminal and which prevents an abnormal voltage applied to the external connection terminal from being input to the signal output terminal. The protection circuit also includes a second protection circuit, which is coupled between a signal input terminal of the internal circuit and the external connection terminal and which prevents the abnormal voltage applied to the external connection terminal from being input to the signal input terminal. The signal input terminal is operatively coupled to the signal output terminal via the first and second protection circuit and has an impedance higher than that of the signal output terminal.

Input/output protection circuit and semiconductor device having the same

A D/A converter includes an analog voltage generating circuit for generating an analog voltage, and an offset-controllable amplifier amplifying the analog voltage with a predetermined amplification factor and outputting an analog output signal. An offset voltage generating circuit generates an offset voltage which is varied on the basis of a digital input signal. The offset voltage controls an offset of the offset-controllable amplifier.

D/A converter including output buffer having a controllable offset

A constant voltage drive type driver circuit includes a pulse transformer for outputting output pulses having a predetermined peak value and having primary and primary windings. The secondary winding has first and second terminals and an equivalent load impedance is connected to the secondary winding when viewed from the pulse transformer excluding an impedance of the secondary winding itself. A power source supplies a voltage, and a switching circuit supplies the voltage from the power source to the primary winding of the pulse transformer in a first mode and cuts off the supply of the voltage to the primary winding in a second mode in response to control signals. A short-circuiting part short-circuits the first and second terminals of the primary winding of the pulse transformer for a predetermined time from a time when the switching circuit assumes the second mode.

Constant voltage drive type driver circuit

A variable attenuator has a plurality of attenuation resistor units, a plurality of switching units, and a plurality of impedance compensation resistor units. The attenuation resistor units are connected in series for attenuating an input signal, and the switching units are provided for the attenuation resistor units. One of the switching units are selected in accordance with a digital control signal supplied from an external source. Each of the impedance compensation resistor units is connected in series with the respective switching units to compensate an output impedance to a specific value regardless of the state of the switching units. Therefore, the variable attenuator of the present invention can correctly control the level of an analog signal by a digital signal.

Variable attenuator for attenuating gain of analog signal in accordance

A D/A converter includes a first resistor network including K resistors each having a resistance, where K is an integer, and a second resistor network including L resistors connected in series where L is an integer. The sum of resistances of the L resistors is approximately equal to the resistance of each of the K resistors. The D/A converter further includes a first switching part, coupled to the K resistors, for selecting (K-1) resistors among the K resistors in accordance with a digital input signal and for forming a series circuit including the (K-1) resistors and the second resistor network connected in series, first and second voltages being applied to respective ends of the series circuit. Furthermore, the D/A converter includes a second switching part, coupled to the second series circuit, for connecting one of the L resistors to an output terminal of the D/A converter.

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Kawasaki, Japan

Osamu Kobayashi