Fujitsu Corporation

Fujitsu Quantum Devices Limited

Fujitsu Microelectronics Limited

Sanki Denshi Kogyo Kabushiki Kaisha

Yoshiaki Kaneko

Naofumi Okubo

Toshiyuki Saito

Yasuyuki Tokumitsu

Shoichi Masui

Takaharu Nakamura

Takeshi Takano

Isao Fukushi

Yukio Takeda

Kazuhisa Tsukahara

Akihito Kumagai

Akihiko Kimura

Shingo Hagiwara

Maya Koyanagi

Amane Inoue

A nonvolatile decision memory unit stores decision data indicating whether data stored in the normal memory cells is true or false. An inversion control circuit sets the inverting signal to a valid level with a predetermined probability. A write circuit writes data having logic which is inverse logic of data to be rewritten to the normal memory cells and writes decision data indicating false to the decision memory unit when the inverting signal indicates a valid level. Since inverse data is rewritten at a predetermined frequency, an imprint is prevented when a read operation is executed repetitively. Moreover, since frequent repeating of reverse polarization of the ferroelectric capacitor due to a rewrite operation is prevented, deterioration of the ferroelectric capacitor due to reverse polarization is minimized. Thus, occurrence of the imprint and deterioration of characteristics in the ferroelectric capacitor is prevented, and the reliability of the ferroelectric memory is improved.

Ferroelectric memory and operating method of same

An information processing apparatus receives a carrier wave modulated in accordance with information and extracts the information and power therefrom to execute a given process. A receiving circuit receives the carrier wave. A dc power generating circuit rectifies the carrier wave received by the receiving circuit to thereby generate dc power. A demodulation circuit is structurally independent of the dc power generating circuit, and retrieves the information modulated onto the carrier wave. An information processing circuit is supplied with the dc power as a power source, and processes the information retrieved by the demodulation circuit in a given manner. Since the demodulation circuit and the dc power generating circuit are structurally independent of each other, interference between elements included in these circuits can be eliminated and simple designing is enabled. In addition, power consumed in the apparatus can be reduced because of optimal designing.

Contactless apparatus and card-type device having clock rectifier that is independent of power rectifier and demodulator with RC time constant based on selectable resistor

Provided are a phase comparator (BBD),for generating a pulse of a signal UP,or DOWN,depending on lead or lag of the falling edge of a clock recovered from DATA, relative to the edge of DATA, an overrun detector circuit,activating an overrun signal OVR while the circuit,detects that lead or lag of the falling edge of the clock exceeds &pgr;/2, a state latch circuit,latching a state of either a signal UP,or DOWN,being active before the signal OVR transits active, and a selection circuit,outputting the signals UP,and DOWN,as signals UP and DOWN while the signal OVR is inactive, and outputting the signals UP,and DOWN,as the signals DOWN and UP while the signal OVR is active.

Error-suppressing phase comparator

A field effect transistor with a reduced delay variation is provided in a compound semiconductor layer with a channel, a source, and a drain region of a first conduction type. A gate electrode, a source electrode, and a drain electrode are formed respectively on the regions mentioned above. Particularly the gate electrode formed on the channel is provided with a projecting part extended in a direction crossing the direction of opposition of the source and drain region and caused to protrude from the channel region. In the compound semiconductor layer, a well region of a second conduction type opposite to the first conduction type is formed so as to enclose the channel region, the source region, the drain region, and the projecting part of the gate electrode more deeply than in the channel, source, and drain regions. The delay variation is markedly reduced by the fact that the gate electrode including the projecting part is enclosed with the well region of the second conduction type.

Field effect transistor with reduced delay variation

A compound semiconductor integrated circuit is adapted to provide an interface with respect to an internal circuit which is driven by first and second power source voltages and operates responsive to a logic signal having a predetermined logic level which is different from an emitter-coupled logic level. The compound semiconductor integrated circuit includes an input circuit part which is driven by the first and third power source voltages and receives an input logic signal having the emitter-coupled logic level, and an output circuit part which is driven by the first and second power source voltages and converts an output signal of the input circuit part into a signal having the predetermined logic level. The second power source voltage is lower than the first power source voltage. The third power source voltage is different from the second power source voltage and is lower than the first power source voltage. The output circuit part supplies an output thereof to the internal circuit.

ECL to GaAs logic level shift interface circuit

An interface circuit provided between a compound semiconductor logic circuit and a bipolar transistor circuit includes an input buffer part for receiving an input signal from the GaAs logic circuit and for outputting a buffered input signal, and an output driver circuit for generating a drive signal from the buffered input signal. The interface circuit also includes an output transistor having a gate connectable to receive the drive signal, a first terminal connectable to receive a first power supply voltage, and a second terminal, and an output terminal connected to the second terminal of the output transistor and the bipolar transistor circuit. Further, the interface circuit includes an output level adjustment circuit which has a first Schottky barrier transistor having a gate, a first terminal connected to the gate of the Schottky barrier transistor and the gate of the output transistor, and a second terminal and which generates a constant voltage applied to the second terminal of the Schottky barrier transistor.

Interface circuit provided between a compound semiconductor logic

A digital two-way radio communication system including first and second radio stations. Each radio station includes an antenna, a data transmission unit, a data reception unit, and a switching circuit. Both radio stations are radio-connected by a single frequency. When a first data transmission unit transmits data to the second radio station, a first switching circuit in the first radio station forms a transmission path between the first data transmission unit and a first antenna, and a second switching circuit in the second radio station forms a reception path between a second antenna and a second data reception unit in the second radio station, or vice versa.

Digital two-way radio-communication system using single frequency

A liquid cooling type high frequency solid state device comprising: a solid state chip; at least one matching circuit connected to the solid state chip; a carrier for mounting the solid state chip and the matching circuit, constituting a solid state circuit to be cooled; a coolant vessel for containing a liquid coolant, with a space for coolant vapor at the top thereof; and an element for condensing the coolant vapor contained in the top space of the vessel. At least a part of the solid state circuit contacts the liquid coolant for boiling and evaporating the coolant. Amplitude modulation of the solid state circuit due to the boiling of the coolant is prevented.

Liquid cooling type high frequency solid state device

A cavity resonator coupling type power distributor/power combiner can be used as a distributing amplifier or a combining unit. A first cavity resonator, having a single coupling terminal, and a second cavity resonator having a plurality of coupling terminals, are coupled by a coupling window or a coupling rod. As a result, a wide bandwidth of microwave electric power can be distributed or combined.

Cavity resonator coupling type power distributor/power combiner

A microwave power distributing and synthesizing device includes: a first base and a second base facing the first base at a predetermined distance and having a hole. A coaxial line element including an inner conductive member coaxially penetrates through the hole of the second base and is spaced from an inner wall of the hole by the second base of a predetermined distance. The coaxial line element is supported on the first base at a bottom end and forms an antenna protruding from the hole of the second base into an input waveguide at a top end. At least one electric field distributing and synthesizing member is arranged perpendicularly to the coaxial line element and a plurality of waveguides are connected to the electric field distributing and synthesizing member. Also, a microwave power amplifying apparatus includes a first microwave power distributing and synthesizing device as described above, for receiving and distributing an input microwave signal; a plurality of amplifiers connected to output ports of the first microwave power distributing and synthesizing device; and a second microwave power distributing and synthesizing device as described above, having input ports connected to the amplifiers.

Microwave power distributing and synthesizing device and microwave power

A cavity resonator coupling-type power distributor/power combiner includes a first cavity resonator operatively resonating with a cylindrical T.sub.O,n,O mode, and a plurality of second cavity resonators arranged on the periphery of the first cavity resonator and extending radially and symmetrically with respect to the first cavity resonator. The second cavity resonators each have the same shape and size so that magnetic-field coupling is established between the first cavity resonator and each of the second cavity resonators, for distributing or combining microwave power in a microwave amplifier.

Cavity resonator coupling-type power distributor/power combiner

Apparatus for preventing the occurrence of possible transient phenomena in the circuit including a power source and its load connected thereto when the supply of electric power from the power source to the load, which has been interrupted, is restarted. The apparatus includes means for detecting the occurrence of the interruption of the power supply and means for memorizing the phase angle of the voltage or current of the power source at the time of the occurrence of the interruption of the power supply to maintain the circuit in off-condition. The apparatus further includes means for detecting the coincidence of the phase angle memorized in the memorizing means with a changing phase angle of voltage or current of the power source after the resupply of the electric power from the source to the load becomes possible whereby, upon detecting the coincidence, resupply of the electric power from the power source to load will be restarted.

Growing community of inventors

Kawasaki, Japan

Yoshiaki Kaneko