Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Toyota Jidosha Kabushiki Kaisha

The University of Tokyo

Kenichi Horiguchi

Takahiro Suzuki

Masatoshi Nakayama

Yukio Ikeda

Yuji Sakai

Haruyasu Senda

Satoshi Miho

Yoshinobu Sasaki

Morishige Hieda

Yoichi Nogami

Kazuhisa Yamauchi

Kenji Mukai

Satoshi Kunugi

Tatsuo Kohama

Akira Inoue

Kazuya Yamamoto

Koji Yamanaka

Yoichi Sato

Yoshihiro Oe

Atsushi Okamura

Ryoji Hayashi

Tadashi Takagi

Hiroshi Otsuka

Shinsuke Watanabe

Hiroaki Sekiyama

Yoshihiro Suda

Norio Higashisaka

Daisuke Yamaguchi

Tomoyuki Asada

Toshiaki Kitano

Yutaro Yamaguchi

Shinichi Miwa

Naoki Kosaka

Shohei Imai

Toshiyuki Namba

Tomokazu Hamada

Satoru Ishizaka

Keisuke Okamoto

Hifumi Noto

Kenichiro Chomei

Shiro Kumano

Shigeo Yamabe

Junichi Nagano

Naoko Nitta

Masakazu Hirobe

Naoko Matsunaga

Kazuyuki Totani

Examples of an amplifier includes an input divider section having a first path and a second path for branching of an input signal, wherein a passing phase at the first path and a passing phase at the second path are different; a first amplifying element that amplifies a signal input to the first path; a second amplifying element that amplifies a signal input to the second path; an output synthesizing section that performs synthesis of an output of the first amplifying element and an output of the second amplifying element with a third path for transmitting the output of the first amplifying element and a fourth path for transmitting the output of the second amplifying element, wherein a passing phase at the third path and a passing phase at the fourth path are different; and an electromagnetic coupling section that establishes electromagnetic coupling of two signals.

Amplifier

Reduction in impedance in a lead connected to a semiconductor element is achieved while achieving anchor effect. The semiconductor device includes a heatsink, a semiconductor element, a lead disposed on an upper side of the heatsink, and a molding material formed to cover the lead, the heatsink, and the semiconductor element. Formed on an edge portion of a lower surface in a position, in the heatsink, overlapping with the lead in a plan view is a first convex portion protruding more than an edge portion of an upper surface in the position, and formed on an edge portion of an upper surface in a position, in the heatsink, which does not overlap with the lead in a plan view is a second convex portion protruding more than an edge portion of a lower surface in the position.

Semiconductor device, high-frequency power amplifier, and method of manufacturing semiconductor device

A field effect transistor includes: a semiconductor substrate having a main surface; a plurality of source electrodes and a plurality of drain electrodes alternately disposed and ohmic-connected with the main surface of the semiconductor substrate; a plurality of gate electrodes Schottky-connected with the main surface of the semiconductor substrate and respectively disposed between the plurality of source electrodes and the plurality of drain electrodes; and a Schottky electrode Schottky-connected with the main surface of the semiconductor substrate, wherein each of the plurality of drain electrodes has first and second portions separated from each other, a sum of widths of the first and second portions of each drain electrode is smaller than a width of one source electrode, the Schottky electrode is disposed between the first portion and the second portion of the drain electrode.

Field effect transistor

An amplifier includes a package, a transistor chip having a gate pad and a drain pad formed elongately, the transistor chip being provided in the package, and a plurality of drain bonding wires connected to the drain pad, wherein the plurality of drain bonding wires include a first outer-most bonding wire connected to one of two end portions of the drain pad, a second outer-most bonding wire connected to the other of the two end portions of the drain pad, and an intermediate bonding wire interposed between the first outer-most bonding wire and the second outer-most bonding wire, each of the plurality of drain bonding wires is longer than 1 mm, and the first outer-most bonding wire and the second outer-most bonding wire have loop heights larger than a loop height that the intermediate bonding wire has.

Amplifier package with multiple drain bonding wires

A comparatorthat detects the difference between a high frequency signal detected by a detectorand a feedback signal A output from a comparator; a comparatorthat detects the difference between the difference detected by the comparatorand a feedback signal B output from an adder; and a loop filterthat passes only a prescribed low frequency band of the output signal of the comparatorare provided, in which an amplitude sensitivity adjusteradjusts the amplitude sensitivity of a variable gain amplifierin accordance with the rate of change of the signal passing through the loop filter, thereby controlling the gain of the variable gain amplifier

Analog feedback amplifier

A semiconductor device includes a power amplifier for amplifying RF signals in multiple frequency bands, an output matching circuit connected to an output of the power amplifier, a first capacitor connected at a first end to an output of the output matching circuit, multiple output paths, a switch connected to a second end of the first capacitor and directing each of the RF signals to a respective one of the output paths in accordance with frequency band of the each of the RF signals, and multiple second capacitors. Each second capacitor is connected in series to a respective one of the output paths. The switch and either the first capacitor or the second capacitors, or both the first and second capacitors, are integrated as a single monolithic microwave integrated circuit.

Semiconductor device

An analog feedback amplifier is capable of suppressing extraneous phase fluctuations and broadening a bandwidth by preventing effects of a group delay element by using an amplitude regulatorand a delay line

An inattentive state determination device includes an observed amount acquiring means for acquiring information on the driver's line of sight and at least one of either information on driving operations or information on the traveling state as an observed amount; and an inattentive state determining means for determining the inattentive state of the driver based on the stochastic relationship between the inattentive state and the observed amount as well as the observed amount acquired by using the observed amount acquiring means. In addition, the inattentive state determining means calculates the probability that the driver is driving inattentively and determines that the driver is driving inattentively when the calculated probability exceeds a threshold.

Inattentive state determination device and method of determining inattentive state

Provided is a low distortion amplifier which can satisfy both securement of a setting space in a vicinity of a transistor and low impedance. The low distortion amplifier includes a short stub having a leading end thereof short-circuited with a high-frequency short-circuit element and a low-frequency short-circuit element, in which the short stub is connected to a vicinity of at least one of a gate terminal and a drain terminal of the transistor, and includes a plurality of branched lines, the plurality of branched lines each having a leading end thereof short-circuited with the high-frequency short-circuit element and the low-frequency short-circuit element.

Low distortion amplifier and Doherty amplifier using low distortion amplifier

Provided is a predistorter which compensates for a memory effect occurring in an amplifier used in a communication device, especially an electric memory effect as well. The predistorter includes: a distortion compensation circuit () for compensating for a nonlinear distortion caused by an amplifier (), in which the distortion compensation circuit outputs a predistortion signal to be input to the amplifier. The predistorter includes: first filter section () which is connected between the distortion compensation circuit and the amplifier, for compensating for a frequency characteristic appearing in a signal component occurring in an entire analog circuit including the amplifier; and second filter section () which is connected between the distortion compensation circuit and the first filter section or between the first filter section and the amplifier, for compensating for a frequency characteristic appearing in a distortion component occurring in the amplifier.

Predistorter

When an input signal level is small, the electrical length of a phase lineand the electrical length of a phase lineare set in such a manner that the impedance seen by looking into the output side from an impedance reference pointat the output side of a carrier amplifierbecomes 2R+&#x3b1; (where R is a load resistance and &#x3b1; is positive), and the electrical length of a phase lineis set at a difference between the electrical length of the phase lineand the electrical length of the phase line

High efficiency amplifier

A dividerfor dividing and distributing a high-frequency signal input from an input terminalto two output sides, a main amplifying unit, connected to one output side of the divider, for amplifying one high-frequency signal output from the divider, a subsidiary amplifying unit, connected to the other output side of the divider, for performing no operation in case of a low instantaneous electric power of the other high-frequency signal output from the dividerand amplifying the other high-frequency signal in case of a high instantaneous electric power of the other high-frequency signal and a circulatorfor injecting the high-frequency signal amplified in the subsidiary amplifying unitinto the output side of the main amplifying unitand injecting the high-frequency signal amplified in the main amplifying unitinto an output terminalare arranged.

High-frequency amplifier, feed-forward amplifier and distortion compensating amplifier

A feedforward amplifier combines an input signal combined by a first error rejection loop with an error component and a first pilot signal detected by a second error detection loop, thereby canceling out the error component and the first pilot signal residual in the input signal.

Feedforward amplifier

A feedforward amplifier combines an input signal delayed by a delay circuit with an output signal by a combiner; down-converts the output of the combiner to a low frequency by a frequency converter; extracts a distortion component from the output of the frequency converter; measures the distortion component by a power detector; and controls a second vector regulator of a distortion canceling loop by a controller such that the distortion component measured becomes minimum.

Conventional distortion compensation circuits have addressed the problem that their distortion compensation amount is greatly reduced at levels other than the designed power level. The present invention provides a distortion compensation circuit that comprises: a vector adjuster; a linearizer; a linear signal extraction path for extracting part of an input signal from the input side of the vector adjuster; a nonlinear signal extraction path for extracting part of an output signal from the output side of the amplifier; a level detector for detecting a combined power level of the signals from the linear signal extraction path and the nonlinear signal extraction path; and a control circuit for adjusting a bias of the linearizer in accordance with the detected combined power level, electrically adjusting the linearizer so that the power detected by the level detector is minimized, and adjusting the vector adjuster so that the power detected by the level detector is minimized every time the linearizer is adjusted. As a result, the distortion compensation circuit of the present invention can optimize distortion compensation at all times independently of the average power changes of the input signal, the secular changes of the amplifier and the state changes of the amplifier caused by temperature changes.

Distortion compensation circuit

Growing community of inventors

Tokyo, Japan

Kenichi Horiguchi