Hitachi, Ltd.

Maxell, Ltd.

Renesas Technology Corp.

Hitachi-high-technologies Corporation

Renesas Electronics Corporation

Nobuhiro Shiramizu

Toru Masuda

Takahiro Nakamura

Osamu Kawamae

Megumi Kurachi

Masuo Oku

Yukinobu Tanaka

Manabu Katsuki

Misako Kono

Katsuyoshi Washio

Satoru Hanzawa

Koichi Watanabe

Akira Kotabe

Hideharu Mikami

Takeshi Kusunoki

Kenichi Ohhata

Fumihiko Arakawa

Masamichi Tanabe

Satoshi Ueno

Hiroshi Mori

Takashi Harada

Nobuhiro Kasa

Kiyoshi Hayashi

Terahertz wave detection equipment comprises: a terahertz wave transceiver including a transmitter for transmitting a terahertz wave and a receiver for receiving a reflected terahertz wave reflected by a background reflected object which exists behind an object to be analyzed; a display; and an information processing apparatus, wherein the transmitter irradiates a terahertz wave based on a transmission signal including a specific frequency toward a two-dimensional area including the object to be analyzed, and the information processing apparatus is configured to analyze concentration of the object to be analyzed based on the reflected terahertz wave and generate a composite image in which a concentration image of the object to be analyzed is combined with an image of the background reflected object.

Terahertz wave detection device, terahertz wave detection method, and terahertz wave detection system

The terahertz wave measuring device includes a pulsed laser light generation unit, a seed light generation unit, a terahertz wave generatorthat generates terahertz waves, a terahertz wave detectoron which the terahertz waves that are generated from the terahertz wave generator and that have interacted with a measurement objectand the pump light are incident and that generates terahertz wave detection light, an interference optical systemthat multiplexes the terahertz wave detection light and reference lightof the same wavelength as the terahertz wave detection light to generate a plurality of interfering light beams, a plurality of light detectorsthat detect the interfering light beams, and a signal processing unitthat outputs an intensity signal and/or a phase signal of the terahertz waves by performing arithmetic operations on the outputs of the plurality of light detectors.

Terahertz wave measuring device

In order to provide a high-sensitivity terahertz wave phase difference measurement system having a high S/N ratio, terahertz interference waves are observed using a half mirror and a movable reference mirror, and the phase difference is calculated, by a terahertz wave generation/detection device that obtains a high S/N ratio by employing a terahertz wave generator for irradiating a non-linear optical crystal with angular phase-matched pump light and seed light, and a terahertz wave detector for irradiating a non-linear optical crystal with angular phase-matched pump light and terahertz waves. In order to match the optical path length of the pump light and the terahertz waves irrespective of the position of the movable reference mirror and the position of a measured object, a first optical delay device, and a second optical delay device that operates in conjunction with movement of a movable reference mirror of a Michelson interferometer, are introduced on the optical path of the pump light.

Terahertz wave phase difference measurement device

The invention is provided to suppress a current supplied to a storage element so as not to vary for each layer in a semiconductor memory device obtained by connecting a plurality of memory cells in series. A semiconductor memory device according to the invention includes a plurality of memory cells connected in series between a first signal line and a second signal line, and supplies a different gate voltage to at least two of selection transistors included in the memory cells, respectively (refer to FIG.).

Series connected resistance change memory device

The time-domain spectroscopy analysis system includes a splitter for splitting pulsed light entered, a variable delayer for delaying timing of a first part of the pulsed light split by the splitter, an electromagnetic wave generator for converting a second part of the pulsed light split by the splitter into an electromagnetic wave, a detector for detecting measurement data from a pulse having passed through a measurement object subjected to the electromagnetic wave emitted from the electromagnetic wave generator, and the pulse outputted from the variable delayer, and a comparator for detecting a phase difference between the pulsed light before being entered into the electromagnetic wave generator and the pulsed light outputted from the variable delayer, wherein a result obtained by the comparator is fed back to the variable delayer.

Time-domain spectroscopy and time-domain spectroscopic analysis system

There is disclosed a variable-gain amplifier circuit that operates on a low voltage, exhibits low distortion, provides a wide range of variation, and is suitable for use in a low-power-consumption wireless communication system. The variable-gain amplifier circuit is configured so that a variable-load circuit, which includes three reactance function elements and provides a wide range of impedance variation, is connected to a conductor circuit whose output terminal generates a positive-phase output current proportional to conductance with respect to an input voltage.

Variable-gain amplifier circuit and wireless communication device integrated circuit equipped therewith

The present invention provides a semiconductor integrated circuit including an active mixer circuit that is operated at low voltage, low noise, and low power consumption. It includes a transconductance amplifier, a transformer, and a multiplier, connects a transformer between the transconductance amplifier and the multiplier, and separates between the transconductance amplifier and the multiplier with respect to direct current inside the transformer. Further, each of the tranconductance amplifier and the multiplier is configured of transistors that are single-stacked between the supply voltage terminal and ground terminal.

Active mixer circuit and a receiver circuit or a millimeter-wave communication unit using it

The variable gain amplifier includes a bias circuit (BC), a matching circuit (MC), a variable gain resistive feedback amplifier (FA)and an output follower (EA). The resistance values of the load resistance Rc and feedback resistance Rf are changed in cooperation. In a case of making the load resistance Rc a high resistance to set the low noise amplifier to a high gain, the feedback resistance Rf is also made a high resistance, the feedback time constant &#x3c4;fb(c)&#x2248;2&#x3c0;&#xb7;RfCbe/(1+gmRc) of the closed loop of the resistive negative feedback amplifierbecomes substantially constant, and then the amplifier has a gain small in frequency dependency over a wide bandwidth. In a case of making the load resistance Rc a low resistance to set the low noise amplifier to a low gain, the feedback resistance Rf is also made a low resistance. The feedback resistance Rf with the low resistance increases the negative feedback quantity, and thus the amplifier is set to a low gain. Also, the load resistance Rc is made a low resistance, and the feedback time constant &#x3c4;fb(c) becomes substantially constant. The gain is not lowered further in a high frequency region.

Semiconductor integrated circuit with variable gain amplifier

Semiconductor devices are provided with high performance high-frequency circuits in which interference caused by inductors is reduced. In a semiconductor device including a modulator circuit to modulate a carrier wave by a base band signal to output an RF signal and a demodulator circuit to demodulate the RF signal by use of the carrier wave to gain the base band signal and a local oscillator to generate the carrier wave, inductors respectively having a closed loop wire are adopted. Interference caused by mutual inductance is reduced by the closed loop wire. For example, where inductors are adopted in the modulator circuit, a closed loop wire is disposed around the outer periphery of the inductors.

Semiconductor devices with inductors

In a variable frequency oscillator in a semiconductor device, as the variation of an oscillation frequency caused by the variation of temperature and supply voltage and process variation is large, it is difficult to reduce the conversion ratio of control voltage dependent upon phase noise and the oscillation frequency and therefore, phase noise is large. The variation of the oscillation frequency is suppressed and phase noise is reduced by connecting a voltage-to-current conversion circuit that converts input control voltage to control current of a ring oscillator to the ring oscillator where delay circuits a delay time of which increases and decreases according to the amplitude of input control current are cascade-connected by a plurality of stages in a ring and increasing/decreasing current dependent upon any of temperature, supply voltage and the threshold voltage of a transistor inside the voltage-to-current conversion circuit.

Variable frequency oscillator and communication circuit with it

The invention provides a transceiver circuit for communication that enhances the operation frequency of a synchronous digital circuit up to the maximum frequency of a flip-flop and inhibits the occurrence of jitters. A clock signal synchronized with data at f/n Hz is converted by a multiplier so that the signal has a frequency of 'n' times so as to use the clock signal for triggering a flip-flop the operation frequency of which is fb/s in the synchronous digital circuit. The multiplier is arranged in the vicinity of the flip-flop triggered by the clock signal of fHz so as to avoid the effect of the deterioration of the operation frequency by interconnect capacitance. The maximum operation frequency of the transceiver circuit determined based upon the operating frequency of the synchronous digital circuit can be enhanced up to the maximum operation frequency of the flip-flop. As a margin can be produced in designing a frequency band of a clock signal processing circuit, the reduction of power consumption, the reduction of phase noise and the extension of a control frequency range can be realized.

Receiver circuit and transmitter circuit

The present invention provides an optical interconnection receiving module that can cancel out the effect of cross talk noise caused by the input signal of another channel on the preamplifier side and the reference amplifier side, and provides suitable device structures for a bypass capacitor used to stabilize supply voltage and for a capacitance device used to cancel out the effect of cross talk noise caused by the input signal of another channel on the preamplifier side and on the reference amplifier side. According to the present invention, there are provided: a photodiode array comprising a plurality of photodiodes, each of which receives an optical signal on a plurality of channels and converts the optical signal into an electric signal; and a receiving circuit for distinguishing an input signal which comprises: a preamplifier for amplifying the electric signal converted from the optical signal by the photodiode array for each of the channels; a comparator; and a reference amplifier for generating reference voltage, wherein a plurality of capacitance devices each equivalent to the photodiode are formed on the semiconductor chip where the receiving circuit is formed, and each of the equivalent capacitance devices is connected between the input terminal of the reference amplifier and a supply voltage terminal.

Growing community of inventors

Tokyo, Japan

Nobuhiro Shiramizu