Patents by Inventor Masashi Nogawa

Masashi Nogawa 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).

  • Publication number: 20220337156
    Abstract: A resonant charge pump circuit includes a resonant circuit having a bucket capacitor and a bucket inductor connected in series, and a switching circuit connected to the resonant circuit. The switching circuit switches to a first state that enables current to flow from an input terminal into the resonant circuit to charge the bucket capacitor and the bucket inductor, and switches to a second state that enables current to flow from the resonant circuit to discharge the bucket capacitor and the bucket inductor to an output terminal. The resonant circuit controls current flow into and out from the resonant circuit when the switching circuit switches between the states. The resonant charge pump circuit also includes a timing circuit that controls when the switching circuit switches between the states.
    Type: Application
    Filed: July 1, 2022
    Publication date: October 20, 2022
    Inventor: Masashi Nogawa
  • Patent number: 11381163
    Abstract: A resonant charge pump circuit includes a resonant circuit having a bucket capacitor and a bucket inductor connected in series, and a switching circuit connected to the resonant circuit. The switching circuit switches to a first state that enables current to flow from an input terminal into the resonant circuit to charge the bucket capacitor and the bucket inductor, and switches to a second state that enables current to flow from the resonant circuit to discharge the bucket capacitor and the bucket inductor to an output terminal. The resonant circuit controls current flow into and out from the resonant circuit when the switching circuit switches between the states. The resonant charge pump circuit also includes a timing circuit that controls when the switching circuit switches between the states.
    Type: Grant
    Filed: July 31, 2019
    Date of Patent: July 5, 2022
    Assignee: ACTIVE-SEMI, INC.
    Inventor: Masashi Nogawa
  • Patent number: 11139737
    Abstract: A voltage regulator control integrated circuit includes constituent parts including an error amplifier circuit, a comparator circuit, a compensation signal generator circuit, an oscillator/one-shot circuit, a latch, and a current sense circuit. In a first example, the integrated circuit is operable in a first mode and in a second mode. In the first mode, the various parts are configured and interconnected in such a way that they operate together as a valley current mode regulator control circuit. In the second mode, the various parts are configured and interconnected in such a way that they operate together as a current-mode constant on-time mode regulator control circuit. In another example, a voltage regulator control integrated circuit has the same basic constituent parts and is operable in a first mode as a peak current mode regulator control circuit, or in a second mode as a constant off-time time mode regulator control circuit.
    Type: Grant
    Filed: May 31, 2019
    Date of Patent: October 5, 2021
    Assignee: Active-Semi, Inc.
    Inventor: Masashi Nogawa
  • Patent number: 10917015
    Abstract: A multiphase operation control method comprises configuring a plurality of power phases of a power converter to operate in an interleaved manner by passing a token sequentially among the plurality of power phases, turning on a first power phase after the first power phase possesses the token and receives a trigger signal from a control circuit of the first power phase, passing the token to a second power phase after the first power phase finishes, passing the token sequentially until a last power phase of the plurality of power phases possesses the token and forwarding the token to the first power phase after the last power phase finishes.
    Type: Grant
    Filed: August 30, 2018
    Date of Patent: February 9, 2021
    Assignee: Active-Semi (BVI) Inc.
    Inventors: Narasimhan Trichy, Masashi Nogawa
  • Publication number: 20200212797
    Abstract: A resonant charge pump circuit includes a resonant circuit having a bucket capacitor and a bucket inductor connected in series, and a switching circuit connected to the resonant circuit. The switching circuit switches to a first state that enables current to flow from an input terminal into the resonant circuit to charge the bucket capacitor and the bucket inductor, and switches to a second state that enables current to flow from the resonant circuit to discharge the bucket capacitor and the bucket inductor to an output terminal. The resonant circuit controls current flow into and out from the resonant circuit when the switching circuit switches between the states. The resonant charge pump circuit also includes a timing circuit that controls when the switching circuit switches between the states.
    Type: Application
    Filed: July 31, 2019
    Publication date: July 2, 2020
    Inventor: Masashi Nogawa
  • Publication number: 20190288602
    Abstract: A voltage regulator control integrated circuit includes constituent parts including an error amplifier circuit, a comparator circuit, a compensation signal generator circuit, an oscillator/one-shot circuit, a latch, and a current sense circuit. In a first example, the integrated circuit is operable in a first mode and in a second mode. In the first mode, the various parts are configured and interconnected in such a way that they operate together as a valley current mode regulator control circuit. In the second mode, the various parts are configured and interconnected in such a way that they operate together as a current-mode constant on-time mode regulator control circuit. In another example, a voltage regulator control integrated circuit has the same basic constituent parts and is operable in a first mode as a peak current mode regulator control circuit, or in a second mode as a constant off-time time mode regulator control circuit.
    Type: Application
    Filed: May 31, 2019
    Publication date: September 19, 2019
    Inventor: Masashi Nogawa
  • Patent number: 10404168
    Abstract: A power converter comprises a first switch and a second switch connected in series between an input power source and ground, an inductor connected between a common node of the first switch and the second switch, and an output capacitor and a comparator having a first input connected to a reference, a second input configured to receive a sum of a first feedback signal and a second feedback signal and an output configured to generate a turn-on signal of the first switch, wherein the first feedback signal is proportional to an voltage across the output capacitor and the second feedback signal is generated by applying at least one low-pass filter to a switching ripple voltage.
    Type: Grant
    Filed: April 10, 2018
    Date of Patent: September 3, 2019
    Assignee: Active-Semi (BVI), Inc.
    Inventors: Narasimhan Trichy, Masashi Nogawa
  • Publication number: 20190207516
    Abstract: A DC-to-DC converter employs peak current mode control and includes a cycle skipping prevent circuit. If a latch is set, then a high side switch is turned on. A comparator receives a signal indicative of current flow and a compensated error signal. The prevent circuit supplies a delayed version of a low duty cycle, fixed frequency, oscillator signal onto the set input lead of the latch. The prevent circuit gates a high signal as output by the comparator onto the reset input lead of the latch. If the output of the comparator has, however, not transitioned high by a predetermined time, then the prevent circuit gates a high pulse onto the reset input lead. Accordingly, the prevent circuit ensures that the latch is reset once every period of the signal SET. A cycle skipping prevent circuit is also disclosed for use in a converter that employs valley current mode control.
    Type: Application
    Filed: November 4, 2018
    Publication date: July 4, 2019
    Inventor: Masashi Nogawa
  • Patent number: 10340797
    Abstract: A voltage regulator control integrated circuit includes constituent parts including an error amplifier circuit, a comparator circuit, a compensation signal generator circuit, an oscillator/one-shot circuit, a latch, and a current sense circuit. In a first example, the integrated circuit is operable in a first mode and in a second mode. In the first mode, the various parts are configured and interconnected in such a way that they operate together as a valley current mode regulator control circuit. In the second mode, the various parts are configured and interconnected in such a way that they operate together as a current-mode constant on-time mode regulator control circuit. In another example, a voltage regulator control integrated circuit has the same basic constituent parts and is operable in a first mode as a peak current mode regulator control circuit, or in a second mode as a constant off-time time mode regulator control circuit.
    Type: Grant
    Filed: November 30, 2017
    Date of Patent: July 2, 2019
    Assignee: Active-Semi, Inc.
    Inventor: Masashi Nogawa
  • Patent number: 10320293
    Abstract: A DC-to-DC converter employs peak current mode control and includes a cycle skipping prevent circuit. If a latch is set, then a high side switch is turned on. A comparator receives a signal indicative of current flow and a compensated error signal. The prevent circuit supplies a delayed version of a low duty cycle, fixed frequency, oscillator signal onto the set input lead of the latch. The prevent circuit gates a high signal as output by the comparator onto the reset input lead of the latch. If the output of the comparator has, however, not transitioned high by a predetermined time, then the prevent circuit gates a high pulse onto the reset input lead. Accordingly, the prevent circuit ensures that the latch is reset once every period of the signal SET. A cycle skipping prevent circuit is also disclosed for use in a converter that employs valley current mode control.
    Type: Grant
    Filed: November 4, 2018
    Date of Patent: June 11, 2019
    Assignee: Active-Semi, Inc.
    Inventor: Masashi Nogawa
  • Publication number: 20190165676
    Abstract: A voltage regulator control integrated circuit includes constituent parts including an error amplifier circuit, a comparator circuit, a compensation signal generator circuit, an oscillator/one-shot circuit, a latch, and a current sense circuit. In a first example, the integrated circuit is operable in a first mode and in a second mode. In the first mode, the various parts are configured and interconnected in such a way that they operate together as a valley current mode regulator control circuit. In the second mode, the various parts are configured and interconnected in such a way that they operate together as a current-mode constant on-time mode regulator control circuit. In another example, a voltage regulator control integrated circuit has the same basic constituent parts and is operable in a first mode as a peak current mode regulator control circuit, or in a second mode as a constant off-time time mode regulator control circuit.
    Type: Application
    Filed: November 30, 2017
    Publication date: May 30, 2019
    Inventor: Masashi Nogawa
  • Patent number: 10291124
    Abstract: A power converter includes a first switch and a second switch connected in series between an input power source and ground, an inductor connected between a common node of the first switch and the second switch, and an output capacitor and a pulse width modulation (PWM) generator configured to generate a gate drive signal for the first switch, wherein a leading edge of the gate drive signal is determined by a comparison result between a reference and a voltage proportional to an output voltage of the power converter and a trailing edge of the gate drive signal is determined by a comparison result between a voltage ramp and a variable voltage source.
    Type: Grant
    Filed: July 2, 2018
    Date of Patent: May 14, 2019
    Assignee: Active-Semi (BVI) Inc.
    Inventors: Narasimhan Trichy, Masashi Nogawa
  • Publication number: 20190074770
    Abstract: A multiphase operation control method comprises configuring a plurality of power phases of a power converter to operate in an interleaved manner by passing a token sequentially among the plurality of power phases, turning on a first power phase after the first power phase possesses the token and receives a trigger signal from a control circuit of the first power phase, passing the token to a second power phase after the first power phase finishes, passing the token sequentially until a last power phase of the plurality of power phases possesses the token and forwarding the token to the first power phase after the last power phase finishes.
    Type: Application
    Filed: August 30, 2018
    Publication date: March 7, 2019
    Inventors: Narasimhan Trichy, Masashi Nogawa
  • Publication number: 20190013733
    Abstract: A power converter comprises a first switch and a second switch connected in series between an input power source and ground, an inductor connected between a common node of the first switch and the second switch, and an output capacitor and a pulse width modulation (PWM) generator configured to generate a gate drive signal for the first switch, wherein a leading edge of the gate drive signal is determined by a comparison result between a reference and a voltage proportional to an output voltage of the power converter and a trailing edge of the gate drive signal is determined by a comparison result between a voltage ramp and a variable voltage source.
    Type: Application
    Filed: July 2, 2018
    Publication date: January 10, 2019
    Inventors: Narasimhan Trichy, Masashi Nogawa
  • Publication number: 20180375429
    Abstract: A power converter comprises a first switch and a second switch connected in series between an input power source and ground, an inductor connected between a common node of the first switch and the second switch, and an output capacitor and a comparator having a first input connected to a reference, a second input configured to receive a sum of a first feedback signal and a second feedback signal and an output configured to generate a turn-on signal of the first switch, wherein the first feedback signal is proportional to an voltage across the output capacitor and the second feedback signal is generated by applying at least one low-pass filter to a switching ripple voltage.
    Type: Application
    Filed: April 10, 2018
    Publication date: December 27, 2018
    Inventors: Narasimhan Trichy, Masashi Nogawa
  • Patent number: 10122272
    Abstract: A DC-to-DC converter employs peak current mode control and includes a cycle skipping prevent circuit. If a latch is set, then a high side switch is turned on. A comparator receives a signal indicative of current flow and a compensated error signal. The prevent circuit supplies a delayed version of a low duty cycle, fixed frequency, oscillator signal onto the set input lead of the latch. The prevent circuit gates a high signal as output by the comparator onto the reset input lead of the latch. If the output of the comparator has, however, not transitioned high by a predetermined time, then the prevent circuit gates a high pulse onto the reset input lead. Accordingly, the prevent circuit ensures that the latch is reset once every period of the signal SET. A cycle skipping prevent circuit is also disclosed for use in a converter that employs valley current mode control.
    Type: Grant
    Filed: December 30, 2017
    Date of Patent: November 6, 2018
    Assignee: Active-Semi, Inc.
    Inventor: Masashi Nogawa
  • Patent number: 8680710
    Abstract: Supply voltage sequencing circuitry includes a first sequencer (10-1) that produces an active level of a Power Good signal PG if a first supply voltage VOUT1 exceeds an upper threshold V90% while a control signal EN_PG is active, and produces an inactive level of PG if EN_PG is inactive. The PG level is latched when a control signal EN is inactive. A Power Down signal PD is produced if VOUT1 is less than a lower threshold V10% while EN is inactive. An active level of PD is produced when EN is active. A power-up sequence of supply voltages VOUT1, VOUT2, and VOUT3 monitored by the first sequencer and similar second (10-2) and third (10-3) sequencers, respectively, is determined by connection of PG of each of the first and second sequencers to control the supply voltage monitored by the next sequencer.
    Type: Grant
    Filed: December 17, 2010
    Date of Patent: March 25, 2014
    Assignee: Texas Instruments Incorporated
    Inventor: Masashi Nogawa
  • Publication number: 20120153992
    Abstract: Supply voltage sequencing circuitry includes a first sequencer (10-1) that produces an active level of a Power Good signal PG if a first supply voltage VOUT1 exceeds an upper threshold V90% while a control signal EN_PG is active, and produces an inactive level of PG if EN_PG is inactive. The PG level is latched when a control signal EN is inactive. A Power Down signal PD is produced if VOUT1 is less than a lower threshold V10% while EN is inactive. An active level of PD is produced when EN is active. A power-up sequence of supply voltages VOUT1, VOUT2, and VOUT3 monitored by the first sequencer and similar second (10-2) and third (10-3) sequencers, respectively, is determined by connection of PG of each of the first and second sequencers to control the supply voltage monitored by the next sequencer.
    Type: Application
    Filed: December 17, 2010
    Publication date: June 21, 2012
    Inventor: Masashi Nogawa
  • Patent number: 7483003
    Abstract: The objective of this invention is to provide a drive circuit and display system that can efficiently transfer prescribed information indicating an abnormality in the drive current supplied to the display elements to a control device. The control data used for controlling the turning on and off of LEDs are shifted sequentially from the first section to the final section of LED drivers 10-1-10-K connected in cascade. In the drive circuit of each section, the control data input from the previous section are held in the first data holding means synchronously with clock signal CLK. Then, the data held in the first data holding means are held in the second data holding means synchronously with latch signal XLAT. Current corresponding to the control data of the second data holding means is supplied to LEDs 40-1-40-M. On the other hand, when new control data are held in the second data holding means, the data indicating prescribed information concerning abnormal functioning of the LED, etc.
    Type: Grant
    Filed: June 9, 2004
    Date of Patent: January 27, 2009
    Assignee: Texas Instruments Incorporated
    Inventor: Masashi Nogawa
  • Patent number: 7009440
    Abstract: The objective of this invention is to provide a pulse signal generator with a simple constitution that can reduce the number of signals required for setting the pulse width, as well as a display device using said pulse signal generator. Pulse assignment signal DP0 input to the initial stage of pulse signal generating units PG(i,0)–PG(i,39) connected in cascade is sequentially transferred towards the last stage of the cascade connection. After transfer of the pulse assignment signal to the pulse signal generating unit in each stage, the count value of said pulse signal generating unit is initialized. Then, the pulses of pulse strings PS0–PS39 in the various pulse signal generating units are counted. The count value of the pulse string is compared to the pulse assignment signal in the comparison unit of each pulse signal generating unit, and, in accordance with the comparison result, the level of the drive pulse signal of the LED is inverted.
    Type: Grant
    Filed: June 7, 2004
    Date of Patent: March 7, 2006
    Assignee: Texas Instruments Incorporated
    Inventors: Masashi Nogawa, Tetsuo Tateishi, Hiroko Nakamura