Patents by Inventor Gwo-Chung Tai

Gwo-Chung Tai 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: 7659783
    Abstract: A phase-locked loop (PLL) to provide clock generation for high-speed memory interface is presented as the innovate PLL (IPLL). The IPLL architecture is able to tolerate external long loop delay without deteriorating jitter performance. The IPLL comprises in part a common mode feedback circuit with a current mode approach, so as to minimize the effects of mismatch in charge-pump circuit, for instance. The voltage-controlled oscillator (VCO) of the IPLL is designed using a mutually interpolating technique generating a 50% duty clock output, beneficial to high-speed double data rate applications. The IPLL further comprises loop filter voltages that are directly connected to each VCO cell of the IPLL. Conventional voltage-to-current (V-I) converter between loop filter and VCO is hence not required. A tight distribution of VCO gain curves is therefore obtained for the present invention across process corners and varied temperatures.
    Type: Grant
    Filed: July 16, 2007
    Date of Patent: February 9, 2010
    Assignee: Micrel, Inc.
    Inventor: Gwo-Chung Tai
  • Patent number: 7635618
    Abstract: The present invention includes a technique for making a dual voltage integrated circuit device. A gate dielectric layer is formed on a semiconductor substrate and a gate material layer is formed on the dielectric layer. A first region of the gate material layer is doped to a first nonzero level and a second region of the gate material level is doped to a second nonzero level greater than the first level. A first field effect transistor is defined that has a first gate formed from the first region. Also, a second field effect transistor is defined that has a second gate formed from the second region. The first transistor is operable at a gate threshold voltage greater than the second transistor in accordance with a difference between the first level and the second level.
    Type: Grant
    Filed: October 12, 2005
    Date of Patent: December 22, 2009
    Assignee: NXP B.V.
    Inventors: Xi-Wei Lin, Gwo-Chung Tai
  • Publication number: 20090021310
    Abstract: A phase-locked loop (PLL) to provide clock generation for high-speed memory interface is presented as the innovate PLL (IPLL). The IPLL architecture is able to tolerate external long loop delay without deteriorating jitter performance. The IPLL comprises in part a common mode feedback circuit with a current mode approach, so as to minimize the effects of mismatch in charge-pump circuit, for instance. The voltage-controlled oscillator (VCO) of the IPLL is designed using a mutually interpolating technique generating a 50% duty clock output, beneficial to high-speed double data rate applications. The IPLL further comprises loop filter voltages that are directly connected to each VCO cell of the IPLL. Conventional voltage-to-current (V-I) converter between loop filter and VCO is hence not required. A tight distribution of VCO gain curves is therefore obtained for the present invention across process corners and varied temperatures.
    Type: Application
    Filed: July 16, 2007
    Publication date: January 22, 2009
    Applicant: MICREL, INC.
    Inventor: Gwo-Chung TAI
  • Publication number: 20080036514
    Abstract: A delay-locked loop (DLL) circuit with mutual-interpolating architecture that provides multiple-phase clock generation is presented. Each delay-cell in the DLL circuit delay chain is effectively an interpolator that combines two input clock signals: one input clock signal is received from the output clock of previous stage in the delay chain, and the other input clock signal is fed back from a following stage. Each delay cell supports the concurrent functions of delay and interpolation. The architecture imposes a set of N simultaneous equations, where N is the total number of delay clock signals, to control the clock waveforms. These simultaneous equations obtain a unique solution when the DLL enters a lock state, and the generated delay clock signals inherently have a clock duty cycle of 50%. The delay chain can be implemented using either odd or even number of delay cells.
    Type: Application
    Filed: August 8, 2006
    Publication date: February 14, 2008
    Applicant: Micrel, Incorporated
    Inventor: Gwo-Chung Tai
  • Patent number: 7330059
    Abstract: A delay-locked loop (DLL) employs an in-loop duty cycle corrector (DCC) to provide accurate multiphase clock generation with 50% duty cycle. Each delay cell can advantageously provide both delay and duty cycle correction functionality. In one embodiment, delay correction can precede duty cycle correction. The bandwidths of the DCC and the DLL can differ by a factor of a decade to achieve fast and stable operation.
    Type: Grant
    Filed: August 24, 2005
    Date of Patent: February 12, 2008
    Assignee: Micrel, Incorporated
    Inventors: Gwo-Chung Tai, Kin Hui
  • Patent number: 7323918
    Abstract: A delay-locked loop (DLL) circuit with mutual-interpolating architecture that provides multiple-phase clock generation is presented. Each delay-cell in the DLL circuit delay chain is effectively an interpolator that combines two input clock signals: one input clock signal is received from the output clock of previous stage in the delay chain, and the other input clock signal is fed back from a following stage. Each delay cell supports the concurrent functions of delay and interpolation. The architecture imposes a set of N simultaneous equations, where N is the total number of delay clock signals, to control the clock waveforms. These simultaneous equations obtain a unique solution when the DLL enters a lock state, and the generated delay clock signals inherently have a clock duty cycle of 50%. The delay chain can be implemented using either odd or even number of delay cells.
    Type: Grant
    Filed: August 8, 2006
    Date of Patent: January 29, 2008
    Assignee: Micrel, Incorporated
    Inventor: Gwo-Chung Tai
  • Publication number: 20070046345
    Abstract: A delay-locked loop (DLL) employs an in-loop duty cycle corrector (DCC) to provide accurate multiphase clock generation with 50% duty cycle. Each delay cell can advantageously provide both delay and duty cycle correction functionality. In one embodiment, delay correction can precede duty cycle correction. The bandwidths of the DCC and the DLL can differ by a factor of a decade to achieve fast and stable operation.
    Type: Application
    Filed: August 24, 2005
    Publication date: March 1, 2007
    Applicant: Micrel, Incorporated
    Inventors: Gwo-Chung Tai, Kin Hui
  • Publication number: 20060046362
    Abstract: The present invention includes a technique for making a dual voltage integrated circuit device. A gate dielectric layer is formed on a semiconductor substrate and a gate material layer is formed on the dielectric layer. A first region of the gate material layer is doped to a first nonzero level and a second region of the gate material level is doped to a second nonzero level greater than the first level. A first field effect transistor is defined that has a first gate formed from the first region. Also, a second field effect transistor is defined that has a second gate formed from the second region. The first transistor is operable at a gate threshold voltage greater than the second transistor in accordance with a difference between the first level and the second level.
    Type: Application
    Filed: October 12, 2005
    Publication date: March 2, 2006
    Inventors: Xi-Wei Lin, Gwo-Chung Tai
  • Publication number: 20040207026
    Abstract: The present invention includes a technique for making a dual voltage integrated circuit device. A gate dielectric layer is formed on a semiconductor substrate and a gate material layer is formed on the dielectric layer. A first region of the gate material layer is doped to a first nonzero level and a second region of the gate material level is doped to a second nonzero level greater than the first level. A first field effect transistor is defined that has a first gate formed from the first region. Also, a second field effect transistor is defined that has a second gate formed from the second region. The first transistor is operable at a gate threshold voltage greater than the second transistor in accordance with a difference between the first level and the second level.
    Type: Application
    Filed: April 29, 2004
    Publication date: October 21, 2004
    Inventors: Xi-Wei Lin, Gwo-Chung Tai
  • Patent number: 6743679
    Abstract: The present invention includes a technique for making a dual voltage integrated circuit device. A gate dielectric layer is formed on a semiconductor substrate and a gate material layer is formed on the dielectric layer. A first region of the gate material layer is doped to a first nonzero level and a second region of the gate material level is doped to a second nonzero level greater than the first level. A first field effect transistor is defined that has a first gate formed from the first region. Also, a second field effect transistor is defined that has a second gate formed from the second region. The first transistor is operable at a gate threshold voltage greater than the second transistor in accordance with a difference between the first level and the second level.
    Type: Grant
    Filed: April 19, 2002
    Date of Patent: June 1, 2004
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Xi-Wei Lin, Gwo-Chung Tai
  • Patent number: 6614842
    Abstract: A 100Base-TX receiver employs a finite impulse response (FIR) filter to provide both equalization and insertion loss compensation for an MLT-3 input signal. The FIR filter includes three delay stages, each delaying the input signal with an 8 ns delay (the period of one data cycle of the MLT-3 input signal), a set of three amplifiers for amplifying the delay stage outputs with gains C1, C2 and C3, and a summer for summing the outputs of the three amplifiers to produce a compensated, equalized MLT-3 signal. A low-pass filter filters the FIR filter output signal, and a data slicer digitizes the low-pass filter output during each data cycle to produce data representing the incoming MLT-3 as having one of six levels. An adaptive control signal processes the slicer output data to determine how to set the gains C1, C2 and C3 of the three FIR amplifiers to provide the correct amount of equalization and compensation.
    Type: Grant
    Filed: July 13, 2000
    Date of Patent: September 2, 2003
    Assignee: Infineon Technologies North America
    Inventors: Gerchih Chou, Gwo-Chung Tai
  • Publication number: 20020164846
    Abstract: The present invention includes a technique for making a dual voltage integrated circuit device. A gate dielectric layer is formed on a semiconductor substrate and a gate material layer is formed on the dielectric layer. A first region of the gate material layer is doped to a first nonzero level and a second region of the gate material level is doped to a second nonzero level greater than the first level. A first field effect transistor is defined that has a first gate formed from the first region. Also, a second field effect transistor is defined that has a second gate formed from the second region. The first transistor is operable at a gate threshold voltage greater than the second transistor in accordance with a difference between the first level and the second level.
    Type: Application
    Filed: April 19, 2002
    Publication date: November 7, 2002
    Inventors: Xi-Wei Lin, Gwo-Chung Tai