Patents by Inventor Ark-Chew Wong

Ark-Chew Wong 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: 20190372587
    Abstract: A DAC driver includes a number of DAC drivers coupled to a load network. A first DAC driver includes a first set of data switches that can be controlled by a first digital input signal. The first DAC driver further includes a first set of output switches, a first set of dump switches and a first set of current sources. Another DAC driver includes a second set of output switches, dump switches, and current sources. The first set of output switches or the second set of output switches are operable to respectively couple either one of the first set of data switches or the first set of current sources to the load network. The first set of dump switches or the second set of dump switches are operable to respectively dump the first set of current sources or the second set current sources into a respective dump load.
    Type: Application
    Filed: December 19, 2017
    Publication date: December 5, 2019
    Applicant: Jariet Technologies, Inc.
    Inventors: Ark-Chew WONG, Richard Dennis ALEXANDER
  • Publication number: 20190041896
    Abstract: A band-pass clock distribution circuit includes a clock tree circuit including at least one clock buffer circuit. The clock tree circuit may be configured to receive a first clock signal from a clock generator circuit and to generate a second clock signal based on the first clock signal. A band-pass filter may be configured to receive the second clock signal and to provide a third clock signal to one or more load circuits. The band-pass filter includes a filtering resonant network including a first inductor and a second inductor coupled to one another at a center tap. The filtering resonant network is configurable to resonate with a parasitic capacitance associated with the one or more load circuits. A portion of the band-pass filter is integrated with the clock tree circuit.
    Type: Application
    Filed: February 17, 2017
    Publication date: February 7, 2019
    Inventors: Ark-Chew WONG, Richard Dennis ALEXANDER, Clifford N. DUONG
  • Publication number: 20190036541
    Abstract: A hybrid digital-to-analog converter (DAC) driver circuit includes a current-mode DAC driver, a voltage-mode DAC driver, and a combination circuit. The current-mode DAC driver may be configured to receive a first set of bits of a digital input signal and to generate a first analog signal. The voltage-mode DAC driver may be configured to receive a second set of bits of the digital input signal and to generate a second analog signal. The combination circuit may be configured to combine the first analog signal and the second analog signal and to generate an analog output signal. The DAC driver circuit may be terminated by adjusting resistor values of the voltage-mode DAC driver. The current-mode DAC driver and the voltage-mode DAC driver are differential drivers, and may be configured to operate with a single clock signal.
    Type: Application
    Filed: March 30, 2017
    Publication date: January 31, 2019
    Inventors: Ark-Chew WONG, Richard Dennis ALEXANDER
  • Patent number: 8847811
    Abstract: Examples are provided for converting an analog signal to a digital output signal using serial-ripple analog-to-digital conversion (ADC). An ADC circuit may include conversion stages coupled in series. Each conversion stage may generate a bit for the digital output signal. A data latch may receive bits for the digital output signal from the conversion stages and to provide the digital output signal based on the bits. A conversion stage may include a comparator circuit and a multiplexer circuit. The comparator circuit may compare a sampled input signal with a reference signal and to generate the associated bit of the digital output signal based on a result of the comparison. The multiplexer circuit may provide an associated reference signal to a comparator circuit of a next conversion stage, where the next conversion stage is subsequent to the conversion stage.
    Type: Grant
    Filed: February 8, 2012
    Date of Patent: September 30, 2014
    Assignee: Semtech Corporation
    Inventors: Ark-Chew Wong, Olivier Jacques Nys, Jonathan Muller
  • Patent number: 8830109
    Abstract: A pipeline analog-to-digital converter is disclosed. An example of a pipeline analog-to-digital converter comprises a plurality of stages. Each of the plurality of stages comprises an analog-to-digital conversion circuit comprising a comparator configured to produce an n-bit digital domain output; and a switchable conductance digital-to-analog conversion circuit operatively coupled to the comparator and configured to switch between at least two conductance values in response to a value of the n-bit digital domain output.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: September 9, 2014
    Assignee: Semtech Corporation
    Inventors: Ark-Chew Wong, Masashi Yamagata
  • Publication number: 20140133524
    Abstract: A differential resistor-based digital-to-analog converter (RDAC) can include a positive digital-to-analog converter (PDAC) stage and a negative digital-to-analog converter (NDAC) stage. A first network of resistors of the PDAC stage can be electrically coupled to a second network of resistors of the NDAC stage utilizing an intermediary network of resistors. Further, a differential receiver can include a first input and a second input. The first input can be electrically coupled to a first resistor of the intermediary network of resistors, and the second input can be electrically coupled to a second resistor of the intermediary network of resistors. Furthermore, a portion of the first network of resistors can be electrically coupled to a positive output of the RDAC, and another portion of the second network of resistors can be electrically coupled to a negative output of the RDAC.
    Type: Application
    Filed: November 9, 2012
    Publication date: May 15, 2014
    Applicant: Semtech Corporation
    Inventor: Ark Chew Wong
  • Patent number: 8717213
    Abstract: A differential resistor-based digital-to-analog converter (RDAC) can include a positive digital-to-analog converter (PDAC) stage and a negative digital-to-analog converter (NDAC) stage. A first network of resistors of the PDAC stage can be electrically coupled to a second network of resistors of the NDAC stage utilizing an intermediary network of resistors. Further, a differential receiver can include a first input and a second input. The first input can be electrically coupled to a first resistor of the intermediary network of resistors, and the second input can be electrically coupled to a second resistor of the intermediary network of resistors. Furthermore, a portion of the first network of resistors can be electrically coupled to a positive output of the RDAC, and another portion of the second network of resistors can be electrically coupled to a negative output of the RDAC.
    Type: Grant
    Filed: November 9, 2012
    Date of Patent: May 6, 2014
    Assignee: Semtech Corporation
    Inventor: Ark Chew Wong
  • Patent number: 8618975
    Abstract: Examples are provided for converting an analog signal to a digital signal by processing more than one bit per cycle in a number of successive approximation cycles. A system may include capacitive sub-DAC circuits and comparators. Switches may isolate the capacitive sub-DAC circuits during one or more first cycles, and merge the sub-DAC circuits during one or more last cycles. A successive approximation register (SAR) may generate digital output signals or DAC digital signals. In another example, a system may include a DAC circuit. An input capacitor may be pre-charged to at least one of an analog input signal and a DAC analog signal. A programmable gain amplifier may amplify an error signal. A multi-bit ADC may convert the amplified error signal to a multi-bit digital signal. An SAR may use the multi-bit digital signal to generate a DAC digital signal or a digital output signal.
    Type: Grant
    Filed: October 26, 2011
    Date of Patent: December 31, 2013
    Assignee: Semtech Corporation
    Inventors: Olivier Nys, Ark-Chew Wong
  • Patent number: 8593325
    Abstract: Examples of systems and methods are provided for converting an analog input signal to a digital output signal. A system may include a current mode (CM) digital-to-analog converter (DAC) circuit to provide a DAC current. A comparator circuit may be configured to generate a comparator signal in response to an error signal determined based on the DAC current and the analog input signal. A successive approximation register circuit may be configured to generate at least one of a DAC-code signal or the digital output signal, in response to the comparator signal. The DAC-code signal may be used by the CM DAC circuit to control the DAC current.
    Type: Grant
    Filed: November 2, 2011
    Date of Patent: November 26, 2013
    Assignee: Semtech Corporation
    Inventors: Ark-Chew Wong, Olivier Jacques Nys
  • Publication number: 20130201043
    Abstract: Examples are provided for converting an analog signal to a digital output signal using serial-ripple analog-to-digital conversion (ADC). An ADC circuit may include conversion stages coupled in series. Each conversion stage may generate a bit for the digital output signal. A data latch may receive bits for the digital output signal from the conversion stages and to provide the digital output signal based on the bits. A conversion stage may include a comparator circuit and a multiplexer circuit. The comparator circuit may compare a sampled input signal with a reference signal and to generate the associated bit of the digital output signal based on a result of the comparison. The multiplexer circuit may provide an associated reference signal to a comparator circuit of a next conversion stage, where the next conversion stage is subsequent to the conversion stage.
    Type: Application
    Filed: February 8, 2012
    Publication date: August 8, 2013
    Applicant: SEMTECH CORPORATION
    Inventors: Ark-Chew WONG, Olivier Jacques NYS, Jonathan MULLER
  • Patent number: 8487800
    Abstract: Examples of resistive digital-to-analog converter (RDAC) circuits are provided herein. RDAC circuits may provide an analog output signal derived from an n-bit digital input signal. In one example, an RDAC circuit may include a plurality of resistive circuit branches. Each resistive circuit branch may be arranged in a pull up/pull down network configuration. For example, an RDAC circuit may include a plurality of resistive circuit branches positioned in parallel. In an example, each of the plurality of resistive circuit branches may include a first inverter circuit, a second inverter circuit, and a resistive component. The RDAC circuit may include an output node for providing the analog output signal. Additionally, methods are provided for converting an analog output signal derived from an n-bit digital input signal.
    Type: Grant
    Filed: November 14, 2011
    Date of Patent: July 16, 2013
    Assignee: Semtech Corporation
    Inventors: Ark-Chew Wong, Jonathan Muller
  • Publication number: 20130120176
    Abstract: Examples of resistive digital-to-analog converter (RDAC) circuits are provided herein. RDAC circuits may provide an analog output signal derived from an n-bit digital input signal. In one example, an RDAC circuit may include a plurality of resistive circuit branches. Each resistive circuit branch may be arranged in a pull up/pull down network configuration. For example, an RDAC circuit may include a plurality of resistive circuit branches positioned in parallel. In an example, each of the plurality of resistive circuit branches may include a first inverter circuit, a second inverter circuit, and a resistive component. The RDAC circuit may include an output node for providing the analog output signal. Additionally, methods are provided for converting an analog output signal derived from an n-bit digital input signal.
    Type: Application
    Filed: November 14, 2011
    Publication date: May 16, 2013
    Applicant: Semtech Corporation
    Inventors: Ark-Chew WONG, Jonathan Muller
  • Publication number: 20130106630
    Abstract: Examples of systems and methods are provided for converting an analog input signal to a digital output signal. A system may include a current mode (CM) digital-to-analog converter (DAC) circuit to provide a DAC current. A comparator circuit may be configured to generate a comparator signal in response to an error signal determined based on the DAC current and the analog input signal. A successive approximation register circuit may be configured to generate at least one of a DAC-code signal or the digital output signal, in response to the comparator signal. The DAC-code signal may be used by the CM DAC circuit to control the DAC current.
    Type: Application
    Filed: November 2, 2011
    Publication date: May 2, 2013
    Applicant: SEMTECH CORPORATION
    Inventors: Ark-Chew Wong, Olivier Jacques Nys
  • Publication number: 20130106629
    Abstract: Examples are provided for converting an analog signal to a digital signal by processing more than one bit per cycle in a number of successive approximation cycles. A system may include capacitive sub-DAC circuits and comparators. Switches may isolate the capacitive sub-DAC circuits during one or more first cycles, and merge the sub-DAC circuits during one or more last cycles. A successive approximation register (SAR) may generate digital output signals or DAC digital signals. In another example, a system may include a DAC circuit. An input capacitor may be pre-charged to at least one of an analog input signal and a DAC analog signal. A programmable gain amplifier may amplify an error signal. A multi-bit ADC may convert the amplified error signal to a multi-bit digital signal. An SAR may use the multi-bit digital signal to generate a DAC digital signal or a digital output signal.
    Type: Application
    Filed: October 26, 2011
    Publication date: May 2, 2013
    Applicant: SEMTECH CORPORATION
    Inventors: Olivier NYS, Ark-Chew Wong
  • Patent number: 8289046
    Abstract: According to one exemplary embodiment, an active termination circuit includes at least one active termination branch, where the at least one active termination branch includes at least one transistor for providing an active termination output. The at least one active termination branch further includes an amplifier driving the at least one transistor, where the amplifier has a non-inverting input coupled to the active termination output via a feedback network. The amplifier controls a current flowing through the at least one transistor so as to provide the active termination output. The active termination output can be provided at a drain of the at least one transistor, where a source of the at least one transistor is coupled to ground through a degeneration transistor and a tail current sink.
    Type: Grant
    Filed: June 30, 2011
    Date of Patent: October 16, 2012
    Assignee: Broadcom Corporation
    Inventors: Joseph Aziz, Andrew Chen, Derek Tam, Ark-Chew Wong, Agnes Neves Woo, Marcel Lugthart
  • Patent number: 8228091
    Abstract: Disclosed is a false-link protection circuit comprising at least one native switch coupled between a communication terminal of a first differential switch and a communication terminal of a second differential switch. The at least one native switch is configured to provide an attenuation path for a pulse link signal received by either communication terminal when the first and second differential switches are in a powered down state. According to one embodiment, a method to attenuate a pulse link signal comprises activating a native switch of a false-link protection circuit by powering down first and second differential switches, receiving a pulse link signal at a communication terminal of one of the first and second differential switches, and attenuating the pulse link signal by diverting it through the false-link protection circuit when the first and second differential switches are in a powered down state.
    Type: Grant
    Filed: February 25, 2010
    Date of Patent: July 24, 2012
    Assignee: Broadcom Corporation
    Inventors: Ark-Chew Wong, Joseph Aziz, Derek Tam, Kevin Chan
  • Patent number: 8183885
    Abstract: In one embodiment, a circuit for providing a tail current for a line driver includes an adjustable current source. The adjustable current source includes a number of current source cells coupled together in a parallel configuration, where the current source cells are configured to provide the tail current for the line driver in response to a digital control signal. The circuit can further include a digital core coupled to the adjustable current source, where the digital core provides the digital control signal. The digital control signal provides a number of bits, where each bit controls one of the current source cells. In one embodiment, a current source cell can comprise a number of current source sub-cells. The current source cells can be configured to provide the tail current for the line driver in response to the digital control signal when the line driver is operating in a class AB mode.
    Type: Grant
    Filed: April 8, 2009
    Date of Patent: May 22, 2012
    Assignee: Broadcom Corporation
    Inventors: Joseph Aziz, Andrew Chen, Ark-Chew Wong, Derek Tam
  • Publication number: 20110254584
    Abstract: According to one exemplary embodiment, an active termination circuit includes at least one active termination branch, where the at least one active termination branch includes at least one transistor for providing an active termination output. The at least one active termination branch further includes an amplifier driving the at least one transistor, where the amplifier has a non-inverting input coupled to the active termination output via a feedback network. The amplifier controls a current flowing through the at least one transistor so as to provide the active termination output. The active termination output can be provided at a drain of the at least one transistor, where a source of the at least one transistor is coupled to ground through a degeneration transistor and a tail current sink.
    Type: Application
    Filed: June 30, 2011
    Publication date: October 20, 2011
    Applicant: BROADCOM CORPORATION
    Inventors: Joseph Aziz, Andrew Chen, Derek Tam, Ark-Chew Wong, Agnes Neves Woo, Marcel Lugthart
  • Publication number: 20110204967
    Abstract: Disclosed is a false-link protection circuit comprising at least one native switch coupled between a communication terminal of a first differential switch and a communication terminal of a second differential switch. The at least one native switch is configured to provide an attenuation path for a pulse link signal received by either communication terminal when the first and second differential switches are in a powered down state. According to one embodiment, a method to attenuate a pulse link signal comprises activating a native switch of a false-link protection circuit by powering down first and second differential switches, receiving a pulse link signal at a communication terminal of one of the first and second differential switches, and attenuating the pulse link signal by diverting it through the false-link protection circuit when the first and second differential switches are in a powered down state.
    Type: Application
    Filed: February 25, 2010
    Publication date: August 25, 2011
    Applicant: BROADCOM CORPORATION
    Inventors: Ark-Chew Wong, Joseph Aziz, Derek Tam, Kevin Chan
  • Patent number: 7982491
    Abstract: According to one exemplary embodiment, an active termination circuit includes at least one active termination branch, where the at least one active termination branch includes at least one transistor for providing an active termination output. The at least one active termination branch further includes an amplifier driving the at least one transistor, where the amplifier has a non-inverting input coupled to the active termination output via a feedback network. The amplifier controls a current flowing through the at least one transistor so as to provide the active termination output. The active termination output can be provided at a drain of the at least one transistor, where a source of the at least one transistor is coupled to ground through a degeneration transistor and a tail current sink.
    Type: Grant
    Filed: April 8, 2009
    Date of Patent: July 19, 2011
    Assignee: Broadcom Corporation
    Inventors: Joseph Aziz, Andrew Chen, Derek Tam, Ark-Chew Wong, Agnes Neves Woo, Marcel Lugthart