Patents by Inventor Hiroki Kikuchi
Hiroki Kikuchi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11962246Abstract: The present disclosure provides a power supply control device and a flyback converter. The power supply control device includes: a comparator, comparing a current sensing signal generated by IN conversion of a primary side current flowing in the primary winding with a threshold voltage; a switching controller, turning off a switching element according to a comparing result of the current sensing signal and the threshold voltage by the comparator; an external terminal, connectable to a connection node of an external resistor connected in series between one end of the auxiliary winding and an application end of a ground potential; a current detector, detecting a terminal current flowing through the external terminal; and a threshold voltage corrector, correcting the threshold voltage based on a current detection signal of the current detector.Type: GrantFiled: January 26, 2022Date of Patent: April 16, 2024Assignee: Rohm Co., Ltd.Inventor: Hiroki Kikuchi
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Publication number: 20240014727Abstract: A power control device (40) includes a feedback voltage generator (401), which generates as a differential current (I_DF) the difference between a first current (I_VDS) generated by a first resistor (59) having one terminal connectable to a current input terminal (DRAIN terminal) and a second current (I_VH) generated by a second resistor (58) having one terminal connectable to an application terminal for an input voltage (VIN) and which generates a feedback voltage (V1) based on the differential current generated.Type: ApplicationFiled: November 22, 2021Publication date: January 11, 2024Inventor: Hiroki KIKUCHI
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Publication number: 20220410407Abstract: A tool exchange device includes a first coupling member attached to one of a body side of an apparatus and a tool side and having a first coupling surface, and a second coupling member attached to the other of the body side and the tool side and having a second coupling surface capable of being in contact with the first coupling surface, in which the first coupling member includes, on the first coupling surface, a first pin, a second pin, and an auxiliary projection, the second coupling member includes, on the second coupling surface, a first hole, a second hole, and an auxiliary hole, a first gap is provided each between the first pin and the first hole and between the second pin and the second hole, a second gap is provided between the auxiliary projection and the auxiliary hole, and the second gap is larger than the first gap.Type: ApplicationFiled: October 30, 2020Publication date: December 29, 2022Inventors: Ryosuke MATSUMOTO, Hiroki KIKUCHI
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Publication number: 20220255437Abstract: The present disclosure provides a power supply control device and a flyback converter. The power supply control device includes: a comparator, comparing a current sensing signal generated by IN conversion of a primary side current flowing in the primary winding with a threshold voltage; a switching controller, turning off a switching element according to a comparing result of the current sensing signal and the threshold voltage by the comparator; an external terminal, connectable to a connection node of an external resistor connected in series between one end of the auxiliary winding and an application end of a ground potential; a current detector, detecting a terminal current flowing through the external terminal; and a threshold voltage corrector, correcting the threshold voltage based on a current detection signal of the current detector.Type: ApplicationFiled: January 26, 2022Publication date: August 11, 2022Inventor: Hiroki KIKUCHI
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Patent number: 11342857Abstract: A synchronous rectification controller that controls driving a synchronous rectification transistor arranged on secondary side, includes: a gate terminal being electrically connectable to a gate of the synchronous rectification transistor; a drain terminal being electrically connectable to a drain of the synchronous rectification transistor via a first resistor; a first comparator comparing a drain terminal voltage generated at the drain terminal with negative first threshold voltage; a second comparator comparing the drain terminal voltage with negative second threshold voltage higher than the first threshold voltage; and a driver performing on/off control of the synchronous rectification transistor based on result of the comparison by the first comparator and result of the comparison by the second comparator, wherein when the synchronous rectification transistor is turned on, voltage is added to the drain terminal voltage by current flowing through the first resistor according to a second resistor.Type: GrantFiled: June 16, 2020Date of Patent: May 24, 2022Assignee: Rohm Co., Ltd.Inventor: Hiroki Kikuchi
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Publication number: 20210275374Abstract: According to an embodiment, a bed apparatus includes a frame, a side rail, and a holder. The holder is secured to the frame. The holder holds the side rail to make the side rail switchable between a first position state where the side rail is in a first position and a second position state where the side rail is in a second position lower than the first position. The holder includes: a lock portion to lock the side rail in the first position state; a cover portion to cover at least part of the lock portion; a lever portion to be operated to release lock of the lock portion; and a stopper portion to make it difficult for the lever portion to operate to release the lock. The bed apparatus that can prevent erroneous release of the lock can be provided.Type: ApplicationFiled: July 30, 2019Publication date: September 9, 2021Inventors: Yusuke SASAKI, Kazuyuki OHHIRA, Hiroki KIKUCHI
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Patent number: 11005356Abstract: A power control device for controlling driving of an LLC resonant converter including a first switching element to one end of which an input voltage is applied, a second switching element of which one end is connected to the other end of the first switching element, and a primary winding and a resonant capacitor connected in series between a first connection node at which the first and second switching elements are connected together and the other end of the second switching element includes an on-timing controller that detects variation of a switching voltage detection signal based on a switching voltage appearing at the first connection node rising up to the input voltage and falling down to 0 V and that, based on the result of the detection, generates a high-side on-signal for turning on the first switching element and a low-side on-signal for turning on the second switching element.Type: GrantFiled: November 5, 2019Date of Patent: May 11, 2021Assignee: Rohm Co., Ltd.Inventors: Hiroki Kikuchi, Hiroyuki Hatano
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Publication number: 20200403520Abstract: A synchronous rectification controller that controls driving a synchronous rectification transistor arranged on secondary side, includes: a gate terminal being electrically connectable to a gate of the synchronous rectification transistor; a drain terminal being electrically connectable to a drain of the synchronous rectification transistor via a first resistor; a first comparator comparing a drain terminal voltage generated at the drain terminal with negative first threshold voltage; a second comparator comparing the drain terminal voltage with negative second threshold voltage higher than the first threshold voltage; and a driver performing on/off control of the synchronous rectification transistor based on result of the comparison by the first comparator and result of the comparison by the second comparator, wherein when the synchronous rectification transistor is turned on, voltage is added to the drain terminal voltage by current flowing through the first resistor according to a second resistor.Type: ApplicationFiled: June 16, 2020Publication date: December 24, 2020Applicant: ROHM CO., LTD.Inventor: Hiroki KIKUCHI
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Patent number: 10770982Abstract: An isolated synchronous rectifying DC/DC converter includes a drain terminal connected to a drain of a synchronous rectification transistor, a source terminal connected to a source of the synchronous rectification transistor; a comparator configured to compare a drain voltage of the drain terminal with a predetermined threshold voltage which set is based on a potential of the source terminal, a first flip-flop to which an OFF signal output from the comparator is input, a driver configured to output a gate signal to the synchronous rectification transistor based on an output signal of the first flip-flop, and a first abnormality detection circuit including an abnormality detection comparator configured to compare a voltage of the source terminal with a detection threshold voltage, and configured to output a first abnormality detection signal based on an output of the abnormality detection comparator.Type: GrantFiled: November 13, 2018Date of Patent: September 8, 2020Assignee: ROHM CO., LTD.Inventor: Hiroki Kikuchi
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Publication number: 20200169160Abstract: A power control device for controlling driving of an LLC resonant converter including a first switching element to one end of which an input voltage is applied, a second switching element of which one end is connected to the other end of the first switching element, and a primary winding and a resonant capacitor connected in series between a first connection node at which the first and second switching elements are connected together and the other end of the second switching element includes an on-timing controller that detects variation of a switching voltage detection signal based on a switching voltage appearing at the first connection node rising up to the input voltage and falling down to 0 V and that, based on the result of the detection, generates a high-side on-signal for turning on the first switching element and a low-side on-signal for turning on the second switching element.Type: ApplicationFiled: November 5, 2019Publication date: May 28, 2020Inventors: Hiroki KIKUCHI, Hiroyuki Hatano
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Patent number: 10566910Abstract: A synchronous rectification controller includes: a drain terminal connected to a drain of a synchronous rectification transistor; a first comparator configured to compare a drain voltage of the drain terminal with a first threshold voltage; a second comparator configured to compare the drain voltage of the drain terminal with a second threshold voltage; a flip-flop to which an ON signal output from the first comparator and an OFF signal output from the second comparator are input; a driver configured to output a gate signal to the synchronous rectification transistor based on an output signal of the flip-flop; and a threshold adjusting part configured to adjust the second threshold voltage based on the drain voltage.Type: GrantFiled: January 14, 2019Date of Patent: February 18, 2020Assignee: ROHM CO., LTD.Inventor: Hiroki Kikuchi
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Patent number: 10554038Abstract: An isolated synchronous rectification type DC/DC converter, includes: a transformer including primary and secondary windings; a switching transistor connected to the primary winding; a synchronous rectifying transistor installed between the secondary winding and a ground line on the secondary side; a photocoupler including a light emitting device and a light receiving device; a feedback circuit driving the light emitting device such that an output voltage of the DC/DC converter approaches a target voltage; a primary side controller connected to the light receiving device and switching the switching transistor depending on feedback signal from the photocoupler; a synchronous rectification controller controlling the rectifying transistor; and a protection circuit including a temperature detection element, one end of the detection element connected to a drain of the rectifying transistor, the protection circuit configured to detect an overheated state of the rectifying transistor depending on a first signal geneType: GrantFiled: June 12, 2017Date of Patent: February 4, 2020Assignee: ROHM CO., LTD.Inventor: Hiroki Kikuchi
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Patent number: 10483863Abstract: A secondary controller drives a light emitting element of a photocoupler such that a detection voltage VOUTS corresponding to an output voltage VOUT generated in an output capacitor C approximates to a reference voltage VREF. A primary controller controls a switching transistor M according to a feedback signal VFB. A protection circuit is activated and drives the light emitting element of the photocoupler when detecting an abnormal state. An auxiliary power supply circuit includes a power supply capacitor C provided separately from the output capacitor C and supplies a power supply voltage VCC to the protection circuit and an anode of the light emitting element of the photocoupler.Type: GrantFiled: August 10, 2018Date of Patent: November 19, 2019Assignee: ROHM CO., LTD.Inventor: Hiroki Kikuchi
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Patent number: 10389255Abstract: A secondary-side module comprises: a synchronous rectification controller that controls a synchronous rectification transistor; and a shunt regulator that generates a current that corresponds to the difference between an output voltage VOUT of a DC/DC converter and the target value of the output voltage, which are housed in a single package. The multiple pins to be connected to the shunt regulator are all laid out along a first side of the package.Type: GrantFiled: March 3, 2016Date of Patent: August 20, 2019Assignee: ROHM CO., LTD.Inventors: Hiroki Kikuchi, Ryo Shimizu
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Patent number: 10381940Abstract: A rectifier IC seals, in a single package, a first transistor chip which integrates a first transistor, a second transistor chip which integrates a second transistor and a controller chip which detects a first node voltage and a second node voltage of each of the transistors so as to perform on/off control on the transistors, and the rectifier IC functions as a secondary-side rectification means of an isolated switching power supply.Type: GrantFiled: January 3, 2018Date of Patent: August 13, 2019Assignee: Rohm Co., Ltd.Inventor: Hiroki Kikuchi
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Publication number: 20190222132Abstract: There is provided an isolated synchronous rectifying DC/DC converter that includes a drain terminal connected to a drain of a synchronous rectification transistor, a source terminal connected to a source of the synchronous rectification transistor; a comparator configured to compare a drain voltage of the drain terminal with a predetermined threshold voltage which set is based on a potential of the source terminal, a first flip-flop to which an OFF signal output from the comparator is input, a driver configured to output a gate signal to the synchronous rectification transistor based on an output signal of the first flip-flop, and a first abnormality detection circuit including an abnormality detection comparator configured to compare a voltage of the source terminal with a detection threshold voltage, and configured to output a first abnormality detection signal based on an output of the abnormality detection comparator.Type: ApplicationFiled: November 13, 2018Publication date: July 18, 2019Inventor: Hiroki KIKUCHI
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Publication number: 20190222134Abstract: A synchronous rectification controller includes: a drain terminal connected to a drain of a synchronous rectification transistor; a first comparator configured to compare a drain voltage of the drain terminal with a first threshold voltage; a second comparator configured to compare the drain voltage of the drain terminal with a second threshold voltage; a flip-flop to which an ON signal output from the first comparator and an OFF signal output from the second comparator are input; a driver configured to output a gate signal to the synchronous rectification transistor based on an output signal of the flip-flop; and a threshold adjusting part configured to adjust the second threshold voltage based on the drain voltage.Type: ApplicationFiled: January 14, 2019Publication date: July 18, 2019Inventor: Hiroki KIKUCHI
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Patent number: 10348212Abstract: A synchronous rectification controller includes a first gate pin coupled to a gate of a first synchronous rectification transistor, a first drain pin coupled to a drain of the first synchronous rectification transistor, a second gate pin coupled to a gate of a second synchronous rectification transistor, a second drain pin coupled to a drain of the second synchronous rectification transistor, a source pin coupled to a ground, a multiplexer selecting a voltage applied to the first drain pin in a first state, and selecting a voltage applied to the second drain pin in a second state, a pulse generator generating a pulse signal based on an output voltage of the multiplexer, a driving circuit switching the first synchronous rectification transistor according to the pulse signal in the first state, and switching the second synchronous rectification transistor according to the pulse signal in the second state.Type: GrantFiled: December 15, 2017Date of Patent: July 9, 2019Assignee: ROHM CO., LTD.Inventor: Hiroki Kikuchi
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Publication number: 20190207523Abstract: An isolated DC/DC converter includes a transformer having a first winding and a secondary winding, a switching transistor connected to the primary winding of the transformer, a rectifier element connected to the secondary winding of the transformer, a photocoupler, a feedback circuit configured to drive a light emitting element on an input side of the photocoupler by a forward current corresponding to an error between an output voltage of the DC/DC converter and a target voltage of the DC/DC converter, a conversion circuit configured to convert a collector current flowing in a light receiving element on an output side of the photocoupler into a feedback voltage having a negative correlation with the collector current, a pulse signal generator configured to generate a pulse signal corresponding to the feedback voltage, and a driver configured to drive the switching transistor depending on the pulse signal.Type: ApplicationFiled: March 8, 2019Publication date: July 4, 2019Inventors: Takumi OE, Hiroyuki MURAKAMI, Hiroki KIKUCHI
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Patent number: 10333415Abstract: A synchronous rectification controller configured to control a synchronous rectification transistor is provided on the secondary side of an insulated synchronous rectification DC/DC converter. A DRAIN pin receives the drain voltage VDS2 of the synchronous rectification transistor. A pulse generator generates a pulse signal S11 based on the voltage at the DRAIN pin. A driver drives the synchronous rectification transistor based on the pulse signal S11. Upon detecting an open-circuit fault of the DRAIN pin, an abnormality detection circuit asserts an abnormality detection signal S13.Type: GrantFiled: June 30, 2017Date of Patent: June 25, 2019Assignee: ROHM CO., LTD.Inventor: Hiroki Kikuchi