Patents Assigned to Sanken Electric Co, Ltd.
  • Publication number: 20180041131
    Abstract: A first switch and a second switch connected in series to both terminals of a DC power source. A signal generation circuit generates a feedback signal based on the DC voltage detected by the voltage detection circuit, and outputs the feedback signal, the feedback signal for turning the first and second switches on and off. A burst oscillation circuit that generates a burst oscillation signal based on a feedback signal and turns the first switch element and the second switch element on and off based on the burst oscillation signal when the standby state is detected. The burst oscillation circuit comprises a capacitor and a rapid charge circuit. When this device returns from standby state to normal state, the rapid charging circuit charges the capacitor after the feedback signal exceeds the cancellation threshold voltage.
    Type: Application
    Filed: August 7, 2017
    Publication date: February 8, 2018
    Applicant: SANKEN ELECTRIC CO., LTD.
    Inventors: Takeki SUGAHARA, Osamu OHTAKE
  • Patent number: 9876101
    Abstract: A semiconductor substrate including a substrate, a buffer layer having a nitride-based semiconductor containing carbon provided on the substrate, a high-resistance layer having a nitride-based semiconductor containing carbon provided on the buffer layer, and a channel layer having a nitride-based semiconductor provided on the high-resistance layer, the high-resistance layer including a first region having carbon concentration lower than that of the buffer layer, and a second region which is provided between the first region and the channel layer, and has the carbon concentration higher than the first region.
    Type: Grant
    Filed: March 12, 2015
    Date of Patent: January 23, 2018
    Assignees: SANKEN ELECTRIC CO., LTD., SHIN-ETSU HANDOTAI CO., LTD
    Inventors: Ken Sato, Hiroshi Shikauchi, Hirokazu Goto, Masaru Shinomiya, Kazunori Hagimoto, Keitaro Tsuchiya
  • Patent number: 9871455
    Abstract: The present invention includes: a series circuit formed of a reactor Lr, a primary winding P of a transformer T, and a capacitor C2; a full-wave rectifier/smoothing circuit D1, D2, C3 configured to perform full-wave rectification and smoothing on a voltage generated in a secondary winding S of the transformer thereby to extract a DC voltage; a control circuit FF1 configured to set a first ON time of the first switch element Q1 and a second ON time of the second switch element Q2 to the same predetermined time thereby to alternately turn on and off the first switch element and the second switch element; and a first ON time controller I1, 16, C7 configured to set one of the first ON time and the second ON time, shorter than the predetermined time, under light-load conditions, based on the DC voltage detected by a detector 11.
    Type: Grant
    Filed: March 30, 2017
    Date of Patent: January 16, 2018
    Assignee: Sanken Electric Co., Ltd.
    Inventors: Osamu Ohtake, Ryuichi Furukoshi
  • Patent number: 9863391
    Abstract: An embodiment of an ignition device comprises an ignition coil including a first winding and a second winding electromagnetically coupled to each other, a first switch electrically connected to a first end of the first winding, a battery electrically connected to a second end of the first winding, a booster with a first end electrically connected to the battery, a second switch electrically connected to a second end of the booster and to the second end of the first winding, and a drive device electrically connected to the first switch, that turns the first switch and the second switch on and off. The drive device feeds a secondary current to the second winding by changing the first switch from an on-state to an off-state, and supplies an output from the booster to the first winding by changing the second switch from an off-state to an on-state.
    Type: Grant
    Filed: December 17, 2015
    Date of Patent: January 9, 2018
    Assignees: SANKEN ELECTRIC CO., LTD., DENSO CORPORATION
    Inventors: Nobuaki Sekine, Shunichi Takeda
  • Patent number: 9851947
    Abstract: An arithmetic processing method is provided using a binary fixed-point arithmetic processing circuit to carry out an operation of multiplicatively dividing a dividend by a divisor. The method comprises shifting the divisor by a specific number of bits when the absolute value of the divisor is within a specific range, and holding the divisor without shifting the divisor when the absolute value of the divisor is out of the specific range, acquiring an initial value of approximation calculation for the divisor that is shifted or held without being shifted, calculating a reciprocal of the divisor by performing asymptotic approximation of the acquired initial value more than once, and calculating a product of the calculated reciprocal and the dividend, and shifting the calculated product by the specific number of bits when the divisor is shifted.
    Type: Grant
    Filed: June 23, 2015
    Date of Patent: December 26, 2017
    Assignee: SANKEN ELECTRIC CO., LTD.
    Inventors: Hiroki Yukiyama, Kazuhiro Mima, Takanaga Yamazaki
  • Patent number: 9847709
    Abstract: A switched-mode power supply device that rectifies and smoothes a direct input voltage to obtain a predetermined output voltage is disclosed. A series circuit includes a reactor and a switching element and the circuit switches the direct input voltage. An OFF time calculator calculates an OFF time of the switching element based on the direct input voltage, the output voltage, and an ON time of the switching element calculated based on the output voltage and a reference value. A frequency calculator calculates at least one of a period and a frequency based on the OFF time calculated by the OFF time calculator and the ON time. A controller that controls switching of the switching element based on a result of comparison between one of the period and the frequency, and a corresponding one of a reference period and the reference frequency.
    Type: Grant
    Filed: September 23, 2016
    Date of Patent: December 19, 2017
    Assignee: SANKEN ELECTRIC CO., LTD.
    Inventor: Toshihiro Nakano
  • Publication number: 20170358994
    Abstract: A switching power supply device that switches setting of an output voltage based on an external signal according to one or more embodiments includes: a transformer including a primary winding and n secondary windings; n synchronous rectification elements provided, corresponding to the n secondary windings; and n?1 switch elements that switch the secondary windings. Each of the n?1 switch elements is kept on or off according to a high or low voltage value out of set voltages of the output voltage, and all or any of the n synchronous rectification elements are selected to synchronously rectify pulse voltage of the secondary windings, and when operation with a high set value of the output voltage stops, a synchronous rectification element used to output the high set value performs switching operation until the output voltage goes down to the low voltage value of the set voltages of the output voltage.
    Type: Application
    Filed: October 30, 2015
    Publication date: December 14, 2017
    Applicant: SANKEN ELECTRIC CO., LTD.
    Inventors: Masao UENO, Mitsutomo YOSHINAGA, Mitsugu FURUYA, Takashi MATSUMOTO
  • Publication number: 20170352537
    Abstract: An epitaxial substrate for electronic devices, including: a Si-based substrate; an AlN initial layer provided on the Si-based substrate; and a buffer layer provided on the AlN initial layer, wherein the roughness Sa of the surface of the AlN initial layer on the side where the buffer layer is located is 4 nm or more. As a result, an epitaxial substrate for electronic devices, in which V pits in a buffer layer structure can be suppressed and longitudinal leakage current characteristics can be improved when an electronic device is fabricated therewith, is provided.
    Type: Application
    Filed: December 18, 2015
    Publication date: December 7, 2017
    Applicants: SHIN-ETSU HANDOTAI CO., LTD., SANKEN ELECTRIC CO., LTD.
    Inventors: Kazunori HAGIMOTO, Masaru SHINOMIYA, Keitaro TSUCHIYA, Hirokazu GOTO, Ken SATO, Hiroshi SHIKAUCHI
  • Publication number: 20170346325
    Abstract: A capacitor discharge circuit according to one or more embodiments includes a capacitor connected in parallel to an alternating-current power source; a rectification element; a first discharge circuit that includes a first diode and a second diode, and causes the capacitor to discharge; a first series circuit including a first capacitor and a second capacitor connected in series between one end of the alternating-current power source and a ground terminal of the rectification element; a second discharge circuit that causes the second capacitor to discharge such that an absolute value of voltage across opposite ends of the second capacitor does not reach a predetermined voltage; and a predetermined period generator that actuates the first discharge circuit after an elapse of a predetermined period of time from stoppage of a discharge operation of the second discharge circuit.
    Type: Application
    Filed: May 23, 2017
    Publication date: November 30, 2017
    Applicant: SANKEN ELECTRIC CO., LTD.
    Inventor: Osamu OHTAKE
  • Publication number: 20170345981
    Abstract: The device is comprised of a backing board, a light-emitting element disposed on the backing board having a laminate structure in which a second semiconductor layer is disposed above a first semiconductor layer, a light-permeable board disposed over the light-emitting element, a first connecting electrode ranging from a first side face of the backing board to a first side face of the light-permeable board and electrically connected to the first semiconductor layer, and a second connecting electrode ranging from a second side face of the backing board to a second side face of the light-permeable board and electrically connected to the second semiconductor layer, wherein connection to the mounting board is established via a second side face of the first connecting electrode and the second connecting electrode, the second side being opposed to a first side face looking to the backing board and the light-permeable board.
    Type: Application
    Filed: July 26, 2017
    Publication date: November 30, 2017
    Applicant: Sanken Electric Co., Ltd.
    Inventors: Tetsuji MATSUO, Yasuhiro MARUO
  • Patent number: 9825027
    Abstract: A semiconductor device has a plurality of transistors, which have first electrodes in first trenches, and includes: two second trenches, which are formed side by side between the first trenches. A second electrode is formed in each of the two second trenches. A first impurity region is formed between the first trench and the second trench; a second impurity region is formed to abut on the first trench; a third impurity region is formed to abut on the second trench; a fourth impurity region, which is formed between two of the second trenches and has a higher impurity concentration than the first impurity region; and a fifth impurity region is formed below the first impurity region and the fourth impurity region. A third electrode is formed to be electrically connected to the first impurity region, the second impurity region, the third impurity region, and the fourth impurity region.
    Type: Grant
    Filed: January 22, 2017
    Date of Patent: November 21, 2017
    Assignee: Sanken Electric Co., LTD.
    Inventors: Shunsuke Fukunaga, Taro Kondo
  • Patent number: 9818828
    Abstract: Apparatus and associated methods relate to an edge-termination structure surrounding a high-voltage MOSFET for reducing a peak lateral electric field. The edge-termination structure includes a sequence of annular trenches and semiconductor pillars circumscribing the high-voltage MOSFET. Each of the annular trenches is laterally separated from the other annular trenches by one of the semiconductor pillars. Each of the annular trenches has dielectric sidewalls and a dielectric bottom electrically isolating a conductive core within each of the annular trenches from a drain-biased region of the semiconductor pillar outside of and adjacent to the annular trench. The conductive core of the innermost trench is biased, while the conductive cores of one or more outer trenches are floating. In some embodiments, a surface of an inner semiconductor pillar is biased as well. The peak lateral electric field can advantageously be reduced by physical arrangement of trenches and electrical biasing sequence.
    Type: Grant
    Filed: March 9, 2016
    Date of Patent: November 14, 2017
    Assignees: POLAR SEMICONDUCTOR, LLC, SANKEN ELECTRIC CO., LTD.
    Inventors: Peter West, Steven Kosier, Tatsuya Kamimura, Don Rankila
  • Patent number: 9818696
    Abstract: A semiconductor device includes: a trench; a first electrode is formed in the trench; a first impurity region, which has a first conductivity type and is formed to abut on the trench; a second impurity region, which has a second conductivity type and is formed to abut the trench; an insulating film, which is formed on the front surface of the semiconductor substrate; a conductive plug, which is formed to penetrate through the insulating film and is electrically connected to the first impurity region and the second impurity region; wherein the conductive plug includes: a silicon layer made of silicon other than a single crystal; a silicide crystallite contained in the silicon layer; and a blocking layer that is formed to cover sides of the silicon layer and is made of a material that is impervious to the silicide crystallites.
    Type: Grant
    Filed: December 26, 2016
    Date of Patent: November 14, 2017
    Assignee: Sanken Electric Co., LTD.
    Inventors: Shunsuke Fukunaga, Taro Kondo, Shinji Kudo
  • Publication number: 20170323960
    Abstract: An epitaxial wafer including: a silicon-based substrate; a first buffer layer on the substrate and including a first multilayer structure buffer region composed of AlxGa1-xN layers and AlyGa1-yN layers (x>y) alternately disposed and a first insertion layer composed of an AlzGa1-zN layer (x>z) and is thicker than the AlyGa1-yN layer, the first regions and insertion layers alternately disposed; a second buffer layer on the first and including a second multilayer structure buffer region composed of Al?Ga1-?N layers and Al?Ga1-?N layers (?>?) alternately disposed and a second insertion layer composed of an Al?Ga1-?N layer (?>?) and is thicker than the Al?Ga1-?N layer, the second regions and insertion layers alternately disposed; and a channel layer on the second buffer layer and thicker than the second insertion layer. The average Al composition in the second buffer layer is higher than that in the first.
    Type: Application
    Filed: November 6, 2015
    Publication date: November 9, 2017
    Applicants: SANKEN ELECTRIC CO., LTD., SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Ken SATO, Hiroshi SHIKAUCHI, Hirokazu GOTO, Masaru SHINOMIYA, Keitaro TSUCHIYA, Kazunori HAGIMOTO
  • Publication number: 20170310209
    Abstract: A rectification circuit rectifies an alternating current voltage of an alternating current power supply. A parallel converter comprises converters that correspond to phases and that are connected in parallel to an output terminal of the rectification circuit. Each converter comprising a reactor, a switching circuit that is connected in series to the reactor and a diode that is connected in series to the reactor. A smoothing capacitor is connected to an output terminal of the parallel converter. A control circuit generates pulse signals corresponding to phases based on an error voltage between an output voltage of the smoothing capacitor and a reference voltage and on an output voltage of the rectification circuit, and switches the switching circuits in the converters using the pulse signals. Current detection circuits are provided corresponding to the converters and that detect currents flowing through the switching circuits.
    Type: Application
    Filed: July 12, 2017
    Publication date: October 26, 2017
    Applicant: SANKEN ELECTRIC CO., LTD.
    Inventor: Hiromitsu TERUI
  • Patent number: 9774262
    Abstract: The present invention includes: a series circuit formed of a reactor Lr, a primary winding P of a transformer T, and a capacitor C2; a full-wave rectifier/smoothing circuit D1, D2, C3 configured to perform full-wave rectification and smoothing on a voltage generated in a secondary winding S of the transformer thereby to extract a DC voltage; a control circuit FF1 configured to set a first ON time of the first switch element Q1 and a second ON time of the second switch element Q2 to the same predetermined time thereby to alternately turn on and off the first switch element and the second switch element; and a first ON time controller I1, I6, C7 configured to set one of the first ON time and the second ON time, shorter than the predetermined time, under light-load conditions, based on the DC voltage detected by a detector 11.
    Type: Grant
    Filed: September 23, 2014
    Date of Patent: September 26, 2017
    Assignee: Sanken Electric Co., Ltd.
    Inventors: Osamu Ohtake, Ryuichi Furukoshi
  • Patent number: 9754740
    Abstract: Disclosed is a switching control circuit for performing an ON-OFF control of a switching element. The switching control circuit includes a first external terminal; a second external terminal; a passive element connected between the first external terminal and the second external terminal; and a function setting circuit, which performs a function setting based on a constant of the passive element. An electric potential at the first external terminal and an electric potential at the second external terminal are controlled.
    Type: Grant
    Filed: November 27, 2015
    Date of Patent: September 5, 2017
    Assignee: Sanken Electric Co., LTD.
    Inventors: Takeki Sugahara, Osamu Ohtake
  • Patent number: 9748850
    Abstract: A switching power-supply device applies a DC voltage to a primary winding of a transformer and performs a switching operation of a switching element connected to a primary winding to generate and output an output voltage to a load. The switching power-supply device includes: an error amplifier, which compares the output voltage with a reference voltage and sends an error voltage as a feedback signal to a primary side; a frequency generation circuit, which generates a switching frequency according to the feedback signal; an off timing determination circuit, which determines a timing at which the switching element is turned off, by comparing a signal depending on the feedback signal with a current flowing through the switching element; and a frequency correction circuit, which corrects the switching frequency generated by the frequency generation circuit, according to an on-duty of the switching element.
    Type: Grant
    Filed: December 17, 2015
    Date of Patent: August 29, 2017
    Assignee: Sanken Electric Co., LTD.
    Inventors: Akira Hayakawa, Masaaki Shimada
  • Patent number: 9742389
    Abstract: A semiconductor device includes a switching element chip, in which a switching element is formed; a first sensing element, which is provided in the switching element chip and is configured to detect first output voltage based on an operating current of the switching element; a second sensing element, which is provided outside the switching element chip and is configured to detect second output voltage based on the operating current of the switching element; and a control circuit, which detects the operating current based on the second output voltage and interrupts the switching element, based on the first output voltage of the first sensing element and the detected operating current, when the switching element is overheated.
    Type: Grant
    Filed: June 6, 2014
    Date of Patent: August 22, 2017
    Assignee: Sanken Electric Co., LTD.
    Inventors: Yuya Maekawa, Katsuyuki Torii
  • Patent number: 9742289
    Abstract: A switching power-supply device has an inductor, a switching element serially connected to the inductor, a control circuit, which controls on and off of the switching element and performs an output voltage control in any one of a plurality of modes including a continuous mode and a discontinuous mode, and a continuous mode detection circuit, which detects that the output voltage control is performed in the continuous mode when a current flowing through the switching element is equal to or greater than a threshold.
    Type: Grant
    Filed: June 23, 2015
    Date of Patent: August 22, 2017
    Assignee: Sanken Electric Co., LTD.
    Inventors: Akira Hayakawa, Mitsutomo Yoshinaga