Patents by Inventor Benedict C. K. Choy

Benedict C. K. Choy 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).

  • Patent number: 9621149
    Abstract: Systems and methods are disclosed for operating a highly linearized resistance for a switch through use of a bootstrapped features. In one exemplary implementation, there is provided a method and system that implements a method for operating a circuit configured to provide a highly linearized resistance including receiving a signal via a bootstrapped switch, coupling the received signal to a gate if the received signal is high, receiving a signal via a switch control input coupled to a high impedance element. Moreover, the method includes coupling the high impedance element to the gate and turning off the switch via a gate turn off when the gate turn off pulls the gate low.
    Type: Grant
    Filed: August 3, 2015
    Date of Patent: April 11, 2017
    Assignee: Microchip Technology Inc.
    Inventors: Benedict C. K. Choy, James T. Walker, Ming-Yuan Yeh
  • Patent number: 9265103
    Abstract: An LED driver circuit for controlling direct current supplied to a plurality of serially connected segments of Light Emitting Diodes (LEDs) is disclosed. In one embodiment, the LED driver circuit comprises a self-commutating circuit, which comprises a plurality of current control elements, each current control element having two ends, a first end connected to a different end of each segment along the plurality of serially connected segments of LEDs and a second end connected to a path to ground. The path to ground comprises a sense resistor and the path to ground is shared by the second end of each current control element. Each current control element is coupled to an adjacent current control element by a cross-regulation circuit and controlled by a signal from an adjacent current control element.
    Type: Grant
    Filed: April 6, 2015
    Date of Patent: February 16, 2016
    Assignee: Microchip Technology Inc.
    Inventors: Scott Lynch, Benedict C. K. Choy
  • Publication number: 20150340435
    Abstract: A circuit module comprises a die attach pad with a surface and a plurality of leads surrounding the surface. A nonconductive adhesive is on the surface. A plurality of electronic circuit dies are on the surface of the die attach pad. Each die has a top surface and a bottom surface with the bottom surface on the adhesive. The top surface has a plurality of bonding pads. A first electronic circuit die has at least one routing path of a conductive material connecting a first bonding pad to a second bonding pad. A first bonding wire connects a bonding pad of a second electronic circuit die to the first bonding pad of the first electronic die. A second bonding wire connects the second bonding pad of the first electronic circuit die to a lead. Where one of the dies contains vertical circuit element, where a doped layer forms a terminal along the bottom surface of the layer, a trench filled with doped polysilicon extends from the top surface to the terminal to connect to the terminal.
    Type: Application
    Filed: June 1, 2015
    Publication date: November 26, 2015
    Inventors: Benedict C.K. Choy, Ching Chu, Haibing (Robin) Liu, Ming-Yuan Yeh
  • Publication number: 20150341024
    Abstract: Systems and methods are disclosed for operating a highly linearized resistance for a switch through use of a bootstrapped features. In one exemplary implementation, there is provided a method and system that implements a method for operating a circuit configured to provide a highly linearized resistance including receiving a signal via a bootstrapped switch, coupling the received signal to a gate if the received signal is high, receiving a signal via a switch control input coupled to a high impedance element. Moreover, the method includes coupling the high impedance element to the gate and turning off the switch via a gate turn off when the gate turn off pulls the gate low.
    Type: Application
    Filed: August 3, 2015
    Publication date: November 26, 2015
    Inventors: BENEDICT C.K. CHOY, JAMES T. WALKER, MING-YUAN YEH
  • Patent number: 9100008
    Abstract: Systems and methods are disclosed for operating a highly linearized resistance for a switch through use of a bootstrapped features. In one exemplary implementation, there is provided a method and system that implements a method for operating a circuit configured to provide a highly linearized resistance including receiving a signal via a bootstrapped switch, coupling the received signal to a gate if the received signal is high, receiving a signal via a switch control input coupled to a high impedance element. Moreover, the method includes coupling the high impedance element to the gate and turning off the switch via a gate turn off when the gate turn off pulls the gate low.
    Type: Grant
    Filed: June 18, 2012
    Date of Patent: August 4, 2015
    Assignee: Microchip Technology Inc.
    Inventors: Benedict C. K. Choy, James T. Walker, Ming-Yuan Yeh
  • Publication number: 20150216004
    Abstract: An LED driver circuit for controlling direct current supplied to a plurality of serially connected segments of Light Emitting Diodes (LEDs) is disclosed. In one embodiment, the LED driver circuit comprises a self-commutating circuit, which comprises a plurality of current control elements, each current control element having two ends, a first end connected to a different end of each segment along the plurality of serially connected segments of LEDs and a second end connected to a path to ground. The path to ground comprises a sense resistor and the path to ground is shared by the second end of each current control element. Each current control element is coupled to an adjacent current control element by a cross-regulation circuit and controlled by a signal from an adjacent current control element.
    Type: Application
    Filed: April 6, 2015
    Publication date: July 30, 2015
    Inventors: Scott Lynch, Benedict C.K. Choy
  • Patent number: 9048104
    Abstract: A circuit module comprises a die attach pad with a surface and a plurality of leads surrounding the surface. A nonconductive adhesive is on the surface. A plurality of electronic circuit dies are on the surface of the die attach pad. Each die has a top surface and a bottom surface with the bottom surface on the adhesive. The top surface has a plurality of bonding pads. A first electronic circuit die has at least one routing path of a conductive material connecting a first bonding pad to a second bonding pad. A first bonding wire connects a bonding pad of a second electronic circuit die to the first bonding pad of the first electronic die. A second bonding wire connects the second bonding pad of the first electronic circuit die to a lead. Where one of the dies contains vertical circuit element, where a doped layer forms a terminal along the bottom surface of the layer, a trench filled with doped polysilicon extends from the top surface to the terminal to connect to the terminal.
    Type: Grant
    Filed: July 12, 2010
    Date of Patent: June 2, 2015
    Assignee: Microchip Technology Inc.
    Inventors: Benedict C. K. Choy, Ching Chu, Haibing (Robin) Liu, Ming-Yuan Yeh
  • Patent number: 9000674
    Abstract: An LED driver circuit for controlling direct current supplied to a plurality of serially connected segments of Light Emitting Diodes (LEDs) is disclosed. In one embodiment, the LED driver circuit comprises a self-commutating circuit, which comprises a plurality of current control elements, each current control element having two ends, a first end connected to a different end of each segment along the plurality of serially connected segments of LEDs and a second end connected to a path to ground. The path to ground comprises a sense resistor and the path to ground is shared by the second end of each current control element. Each current control element is coupled to an adjacent current control element by a cross-regulation circuit and controlled by a signal from an adjacent current control element.
    Type: Grant
    Filed: March 28, 2014
    Date of Patent: April 7, 2015
    Assignee: Microchip Technology Inc.
    Inventors: Scott Lynch, Benedict C. K. Choy
  • Publication number: 20150049577
    Abstract: An ultrasound image system has a plurality of channels. At least one of the plurality of channels has a capacitive T/R switch.
    Type: Application
    Filed: August 13, 2013
    Publication date: February 19, 2015
    Inventors: Benedict C.K. Choy, Ching Chu, Andy Tu
  • Publication number: 20140210363
    Abstract: An LED driver circuit for controlling direct current supplied to a plurality of serially connected segments of Light Emitting Diodes (LEDs) is disclosed. In one embodiment, the LED driver circuit comprises a self-commutating circuit, which comprises a plurality of current control elements, each current control element having two ends, a first end connected to a different end of each segment along the plurality of serially connected segments of LEDs and a second end connected to a path to ground. The path to ground comprises a sense resistor and the path to ground is shared by the second end of each current control element. Each current control element is coupled to an adjacent current control element by a cross-regulation circuit and controlled by a signal from an adjacent current control element.
    Type: Application
    Filed: March 28, 2014
    Publication date: July 31, 2014
    Applicant: Supertex, Inc.
    Inventors: Scott Lynch, Benedict C.K. Choy
  • Patent number: 8686651
    Abstract: An LED driver circuit is disclosed. The top of a string of series connected LED segments is connected to the output of a rectifier, which in turn is connected to an AC source. The string is tapped at various locations, including the bottom of the string. Each segment can consists of any number of serial or parallel connected LEDs. Current control elements or regulators sink current at each tap and are sequentially turned on and off one at a time, tracking the rectified sine wave voltage. Voltage across each regulator and current when conducting is individually controllable. The regulators may control current in a multitude of ways, including a constant current, or a current dependent on voltage across the regulators including a resistor, or a combination. The driver is self-commutating, with the sequencing of the current control elements an inherent feature closely integrated with the current control elements and providing optimal performance over variable operating conditions.
    Type: Grant
    Filed: August 15, 2011
    Date of Patent: April 1, 2014
    Assignee: Supertex, Inc.
    Inventors: Scott Lynch, Benedict C. K. Choy
  • Publication number: 20130187551
    Abstract: The present inventions relate to a control circuit for controlling a plurality of serially connected groups of LEDs. A control unit is connected in parallel to each group of a plurality of serially connected groups of LEDs. Each LED group is connected to the adjacent group of LEDs. The control unit is connected to a group of LEDs. The control unit performs the functions of voltage regulating/current regulating/bypass for the associated group of LEDs. The control unit can act as a by-pass unit permitting current to flow through the control unit rather than through the associated group of LEDs.
    Type: Application
    Filed: July 23, 2012
    Publication date: July 25, 2013
    Applicant: Supertex, Inc.
    Inventors: Benedict C.K. CHOY, Marc Tan
  • Publication number: 20130154715
    Abstract: Systems and methods are disclosed for operating a highly linearized resistance for a switch through use of a bootstrapped features. In one exemplary implementation, there is provided a method and system that implements a method for operating a circuit configured to provide a highly linearized resistance including receiving a signal via a bootstrapped switch, coupling the received signal to a gate if the received signal is high, receiving a signal via a switch control input coupled to a high impedance element. Moreover, the method includes coupling the high impedance element to the gate and turning off the switch via a gate turn off when the gate turn off pulls the gate low.
    Type: Application
    Filed: June 18, 2012
    Publication date: June 20, 2013
    Applicant: Supertex, Inc.
    Inventors: Benedict C.K. Choy, James T. Walker, Ming-Yuan Yeh
  • Publication number: 20120262075
    Abstract: An LED driver circuit operating from the AC power line providing high efficiency, good line and load regulation, high power factor, low line current harmonics, low conducted EMI, high LED utilization, and lamp dimming compatibility, while consisting of a minimal number of components. No inductors, nor capacitors (including electrolytics), nor high current switching transistors are employed. The top of a string of series connected LED segments is connected to the output of a rectifier, which in turn is connected to an AC sine wave power source. The string is tapped at various locations, including the bottom of the string. Each segment can consists of any number of serial or parallel connected LEDs. Current control elements or regulators sink current at each tap and are sequentially turned on and off one at a time, tracking the rectified sine wave voltage. Voltage across each regulator and current when conducting is individually controllable.
    Type: Application
    Filed: August 15, 2011
    Publication date: October 18, 2012
    Applicant: Supertex, Inc.
    Inventors: Scott Lynch, Benedict C.K. Choy
  • Patent number: 8254073
    Abstract: A two terminal transmit receive device passes small analog signals with a constant low resistance value to the input of a low noise, low voltage receiver amplifier and can protect the input against the high voltage transmit signals in ultrasound applications without the aid of any power supplies. The device uses depletion-mode transistors that are normally on to pass small analog signal and a voltage detection circuit that quickly turns off the depletion-mode transistors when the presence of high voltage is detected.
    Type: Grant
    Filed: December 21, 2009
    Date of Patent: August 28, 2012
    Assignee: Supertex, Inc.
    Inventors: Benedict C. K. Choy, Jimes Lei
  • Patent number: 8138805
    Abstract: A complementary high voltage switched current source circuit has a complementary current source pair, wherein a first of the current source pair is coupled to a positive voltage rail and a second of the current source pair is coupled to a negative voltage rail. A digital logic-level control interface circuit is coupled to the complementary current source pair and to the positive voltage rail and the negative voltage rail. A pair of high voltage switches is coupled to the complementary current source pair and the digital logic-level control interface circuit and controlled by the digital control interface circuit.
    Type: Grant
    Filed: July 21, 2011
    Date of Patent: March 20, 2012
    Assignee: Supertex, Inc.
    Inventor: Benedict C. K. Choy
  • Publication number: 20120007216
    Abstract: A circuit module comprises a die attach pad with a surface and a plurality of leads surrounding the surface. A nonconductive adhesive is on the surface. A plurality of electronic circuit dies are on the surface of the die attach pad. Each die has a top surface and a bottom surface with the bottom surface on the adhesive. The top surface has a plurality of bonding pads. A first electronic circuit die has at least one routing path of a conductive material connecting a first bonding pad to a second bonding pad. A first bonding wire connects a bonding pad of a second electronic circuit die to the first bonding pad of the first electronic die. A second bonding wire connects the second bonding pad of the first electronic circuit die to a lead. Where one of the dies contains vertical circuit element, where a doped layer forms a terminal along the bottom surface of the layer, a trench filled with doped polysilicon extends from the top surface to the terminal to connect to the terminal.
    Type: Application
    Filed: July 12, 2010
    Publication date: January 12, 2012
    Inventors: Benedict C. K. Choy, Ching Chu, Haibing (Robin) Liu, Ming-Yuan Yeh
  • Publication number: 20110273224
    Abstract: A complementary high voltage switched current source circuit has a complementary current source pair, wherein a first of the current source pair is coupled to a positive voltage rail and a second of the current source pair is coupled to a negative voltage rail. A digital logic-level control interface circuit is coupled to the complementary current source pair and to the positive voltage rail and the negative voltage rail. A pair of high voltage switches is coupled to the complementary current source pair and the digital logic-level control interface circuit and controlled by the digital control interface circuit.
    Type: Application
    Filed: July 21, 2011
    Publication date: November 10, 2011
    Inventor: Benedict C.K. Choy
  • Patent number: 7977820
    Abstract: A ultrasound transmit pulse waveform generator for driving a piezoelectric transducer in medical ultrasound imaging, nondestructive testing (NDT) ultrasound imaging applications, includes a capacitor, switching programmable current sources, and a power amplifier.
    Type: Grant
    Filed: January 15, 2009
    Date of Patent: July 12, 2011
    Assignee: Supertex, Inc.
    Inventors: Ching Chu, Benedict C. K. Choy
  • Patent number: 7956653
    Abstract: A complementary high voltage switched current source circuit has a complementary current source pair, wherein a first of the current source pair is coupled to a positive voltage rail and a second of the current source pair is coupled to a negative voltage rail. A digital logic-level control interface circuit is coupled to the complementary current source pair and to the positive voltage rail and the negative voltage rail. A pair of high voltage switches is coupled to the complementary current source pair and the digital logic-level control interface circuit and controlled by the digital control interface circuit.
    Type: Grant
    Filed: May 4, 2009
    Date of Patent: June 7, 2011
    Assignee: Supertex, Inc.
    Inventors: Benedict C. K. Choy, Ching Chu