Patents by Inventor Chung-Cheng Wang

Chung-Cheng Wang 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: 7301415
    Abstract: A method for automatic frequency tuning in a phase lock loop suitable for use in multi-band VCO wireless systems having very limited initial frequency lock times is disclosed. A predetermined subset of VCOs out of a larger bank of VCOs is selected to serve as interpolation points. The interpolation point VCOs are pre-calibrated with a predetermined voltage and the resultingly generated frequency for each of the interpolation point VCOs is stored into memory as a (frequency, VCO) pair, one pair for each interpolation point VCO. When a desired frequency then is given to the system, an appropriate VCO is selected by interpolation using the (frequency, VCO) pairs of the two most adjacent interpolation points for tracking and locking.
    Type: Grant
    Filed: December 12, 2005
    Date of Patent: November 27, 2007
    Assignee: Airoha Technology Corp.
    Inventors: Chung-Cheng Wang, Chao-Shi Chuang, Wen-Shih Lu, Yu-Chang Chen
  • Publication number: 20070132517
    Abstract: A method for automatic frequency tuning in a phase lock loop suitable for use in multi-band VCO wireless systems having very limited initial frequency lock times is disclosed. A predetermined subset of VCOs out of a larger bank of VCOs is selected to serve as interpolation points. The interpolation point VCOs are pre-calibrated with a predetermined voltage and the resultingly generated frequency for each of the interpolation point VCOs is stored into memory as a (frequency, VCO) pair, one pair for each interpolation point VCO. When a desired frequency then is given to the system, an appropriate VCO is selected by interpolation using the (frequency, VCO) pairs of the two most adjacent interpolation points for tracking and locking.
    Type: Application
    Filed: December 12, 2005
    Publication date: June 14, 2007
    Inventors: Chung-Cheng Wang, Chao-Shi Chuang, Wen-Shih Lu, Yu-Chang Chen
  • Patent number: 7180376
    Abstract: Synthesizer and calibrating method utilizing same. The frequency synthesizer modulates input signals comprising a phase locked loop circuit. The phase locked loop circuit comprises a phase frequency detector for generating a first signal, a low pass filter for outputting a filtered control signal derived from the received first signal, a voltage control oscillator for generating an output signal with a first frequency based on the control signal, a frequency divider dividing the first frequency for output to the input terminal of the phase frequency detector, a modulator coupled to the frequency divider, a pre-emphasis filter receiving and filtering the input signal for output to the modulator, and an auto loop gain calibration circuit, receiving the control signal, and calculating a current gain of the control signal in accordance with the voltage of the control signal to compensate for the frequency response mismatch between the pre-emphasis filter and the frequency synthesizer.
    Type: Grant
    Filed: January 13, 2005
    Date of Patent: February 20, 2007
    Assignee: Airoha Technology Corp.
    Inventors: Chong-Ren Wang, Chao-Shi Chuang, Chung-Cheng Wang
  • Publication number: 20070001770
    Abstract: A PLL is provided, comprising a first divider, a PFD, a loop filter, a VCO, a second divider and a controller. The first divider receives a reference signal and divides the reference signal by R to obtain a divided signal. The PFD compares the divided signal and a feedback signal to generate a compared The VCO selects one of a plurality of operating curves for oscillation based on a selection signal, and generates an oscillation signal based on an operating voltage generated by signal the loop filter. The second divider divides the oscillation signal by N to obtain the feedback signal. The controller operates in an initial mode to recursively determine the selection signal by calculating differences of the feedback signal and the divided signal. When the selection signal converges to stable, the PLL switches to a normal mode to operate on the corresponding operating curve.
    Type: Application
    Filed: June 20, 2006
    Publication date: January 4, 2007
    Applicant: Airoha Technology Corp.
    Inventors: Chung-Cheng Wang, Chao-Shi Chuang, Yi-Chuan Liu
  • Publication number: 20060279446
    Abstract: A radio frequency (RF) receiver is provided, comprising an antenna, a low noise amplifier, a down converter, a first analog to digital converter (ADC), a second ADC, a digital up converter. The antenna receives an RF signal, and the LNA coupled to the antenna amplifies the RF signal. The down converter, coupled to the LNA, down converts the RF signal to generate an in-phase baseband signal and a quadrature baseband signal. The first ADC, coupled to the down converter, digitizes the in-phase baseband signal to an in-phase digital signal. The second ADC, coupled to the down converter, digitizes the quadrature baseband signal to a quadrature digital signal. The digital up converter, coupled to the first and second ADCs, up converts the in-phase digital signal and quadrature digital signal to generate an intermediate frequency (IF) signal.
    Type: Application
    Filed: June 13, 2006
    Publication date: December 14, 2006
    Inventors: Chung-Cheng Wang, John-San Yang
  • Publication number: 20060281433
    Abstract: A demodulation method and apparatus are provided. An RF signal is down converted to generate a first in-phase signal and a first quadrature signal of a first frequency. Limiting amplification is performed on the first in-phase signal and the first quadrature signal to generate a second in-phase signal and a second quadrature signal. The frequency of the second in-phase and quadrature signals are up converted to a third in-phase signal and a quadrature signal of a second frequency. The third in-phase and quadrature signals are up converted to generate an intermediate frequency (IF) signal of a third frequency.
    Type: Application
    Filed: June 13, 2006
    Publication date: December 14, 2006
    Inventors: John-San Yang, Chung-Cheng Wang, Yu-Hua Liu
  • Patent number: 7129572
    Abstract: A submember for electrical device is disclosed. Said submember is mounted on a chip of electrical device. An embodiment for the submember comprised of an insulator and a plurality of conductive elements, wherein the conductive elements embedded in the insulator and a portion of conductive element exposed to the insulator for electrical connection, then (i). the reliability of submember is enhanced; (ii). the material of insulator enables to be saved; and (iii). the thickness of submember is thinner and the heat dissipation of chip enhanced; moreover, a portion of the conductive element may be protruding the insulator for avoiding a short-circuited problem of conductive wire, moreover, the conductive element may be staircase-shaped, then, not only the reliability of submember is enhanced, but the short circuit problem of conductive wire is also avoided; the conductive element may further include an extending portion, furthermore, the conductive element may be placed in a cavity as required.
    Type: Grant
    Filed: August 9, 2005
    Date of Patent: October 31, 2006
    Inventor: Chung-Cheng Wang
  • Patent number: 7047146
    Abstract: A PLL includes a loop filter for accumulating charge to generate a loop-filter voltage and a VCO having a plurality of frequency ranges. The VCO receives the loop-filter voltage and generates an output signal having a frequency according to the loop-filter voltage and a currently selected VCO frequency range. During PLL calibration, the loop-filter is connected to a constant voltage source; the PLL feedback signal is synchronized with the reference signal; a linear search, a binary search, or a memory lookup is used to find a first and a second VCO frequency range; first and second time durations are measured for the time durations between the second rising edges of the reference signal and the PLL feedback signal for the two VCO frequency ranges, and the optimal VCO frequency range is determined by setting the VCO frequency range to be the VCO frequency range having the shortest measured time duration.
    Type: Grant
    Filed: December 19, 2003
    Date of Patent: May 16, 2006
    Assignee: Airoha Technology Corp
    Inventors: Chao-Shi Chuang, Chung-Cheng Wang, Wen-Shih Lu
  • Publication number: 20060097379
    Abstract: Substrate for electrical devices and methods of manufacturing such substrate are disclosed. An embodiment for the substrate comprised of an insulator and a plurality of conductive elements, wherein the conductive elements embedded in the insulator, and two surfaces of the conductive element exposed to two surfaces of the insulator for electrical connection respectively, meanwhile a portion of conductive element may protrude the insulator, in this manner, solder balls are not needed, moreover the conductive element of substrate may further include either an extending portion or a protruding portion, and the present invention may be capable of affording a thinner electrical device thickness, enhanced reliability, and a decreased cost in production.
    Type: Application
    Filed: November 8, 2005
    Publication date: May 11, 2006
    Inventor: Chung-Cheng Wang
  • Publication number: 20060038278
    Abstract: A submember for electrical device is disclosed. Said submember is mounted on a chip of electrical device. An embodiment for the submember comprised of an insulator and a plurality of conductive elements, wherein the conductive elements embedded in the insulator and a portion of conductive element exposed to the insulator for electrical connection, then (i). the reliability of submember is enhanced; (ii).the material of insulator enables to be saved; and (iii).the thickness of submember is thinner and the heat dissipation of chip enhanced; moreover, a portion of the conductive element may be protruding the insulator for avoiding a short-circuited problem of conductive wire, moreover, the conductive element may be staircase-shaped, then, not only the reliability of submember is enhanced, but the short circuit problem of conductive wire is also avoided; the conductive element may further include an extending portion, furthermore, the conductive element may be placed in a cavity as required.
    Type: Application
    Filed: August 9, 2005
    Publication date: February 23, 2006
    Inventor: Chung-Cheng Wang
  • Publication number: 20050157819
    Abstract: A receiver comprising an in-phase channel circuit, a quadrature channel circuit, and a gain imbalance calibration circuit comprising a first circuit and a second circuit. The first circuit provides testing signals to the in-phase channel circuit and the quadrature channel circuit. Test resultant signals output from the in-phase channel circuit and the quadrature channel circuit are input to the second circuit. The second circuit calibrates the gain of baseband amplifiers of the in-phase channel and the quadrature channel circuit according to the offset between the test resultant signals, thereby enabling the test resultant signal of the in-phase channel circuit to be substantially equal to the test resultant signal of the quadrature channel circuit.
    Type: Application
    Filed: January 18, 2005
    Publication date: July 21, 2005
    Inventors: Chung-Cheng Wang, John-San Yang, Yu-Hua Liu
  • Publication number: 20050156676
    Abstract: Synthesizer and calibrating method utilizing same. The frequency synthesizer modulates input signals comprising a phase locked loop circuit. The phase locked loop circuit comprises a phase frequency detector for generating a first signal, a low pass filter for outputting a filtered control signal derived from the received first signal, a voltage control oscillator for generating an output signal with a first frequency based on the control signal, a frequency divider dividing the first frequency for output to the input terminal of the phase frequency detector, a modulator coupled to the frequency divider, a pre-emphasis filter receiving and filtering the input signal for output to the modulator, and an auto loop gain calibration circuit, receiving the control signal, and calculating a current gain of the control signal in accordance with the voltage of the control signal to compensate for the frequency response mismatch between the pre-emphasis filter and the frequency synthesizer.
    Type: Application
    Filed: January 13, 2005
    Publication date: July 21, 2005
    Inventors: Chong-Ren Wang, Chao-Shi Chuang, Chung-Cheng Wang
  • Publication number: 20050137816
    Abstract: A PLL includes a loop filter for accumulating charge to generate a loop-filter voltage and a VCO having a plurality of frequency ranges. The VCO receives the loop-filter voltage and generates an output signal having a frequency according to the loop-filter voltage and a currently selected VCO frequency range. During PLL calibration, the loop-filter is connected to a constant voltage source; the PLL feedback signal is synchronized with the reference signal; a linear search, a binary search, or a memory lookup is used to find a first and a second VCO frequency range; first and second time durations are measured for the time durations between the second rising edges of the reference signal and the PLL feedback signal for the two VCO frequency ranges, and the optimal VCO frequency range is determined by setting the VCO frequency range to be the VCO frequency range having the shortest measured time duration.
    Type: Application
    Filed: December 19, 2003
    Publication date: June 23, 2005
    Inventors: Chao-Shi Chuang, Chung-Cheng Wang, Wen-Shih Lu
  • Publication number: 20050104205
    Abstract: Substrate for electrical devices and methods of manufacturing such substrate are disclosed. An embodiment for the substrate comprised of an insulator and a plurality of conductive elements, wherein the insulator having a recess. The conductive elements embedded in the insulator. The conductive elements extend from the insulator surface to the recess. There are two portions of the conductive elements for electrical connection respectively, wherein a portion of conductive element may protrude the insulator surface for electrical connection. In this manner, solder balls are not needed. Moreover, the substrate of the present invention may also comprise an adhesive mean, which is between the conductive elements and the insulator. In addition, the substrate may further comprise a submember such as a chip, heat spreader etc., and the present invention may be capable of affording a thinner electrical device thickness, enhanced reliability, and a decreased cost in production.
    Type: Application
    Filed: September 21, 2004
    Publication date: May 19, 2005
    Inventor: Chung-Cheng Wang
  • Publication number: 20040047457
    Abstract: A dialing apparatus for international prepaid phone card, the user of which may more rapidly, more conveniently and more accurately place international phone calls. The dialing apparatus is suitable for working with a telephone apparatus so that the user may place phone calls by charging the international prepaid phone card via the telephone apparatus. The dialing apparatus comprises of: an integrated circuit, a keyboard unit connected with the integrated circuit, a memory unit to store the necessary configuration information of the international prepaid phone card and at lease a set of telephone number that the user wishes to call, and a speaker connected with the integrated circuit. While the user wishes to place international phone calls, it is only necessary to press a few keys on the keyboard unit. The integrated circuit will then read the necessary configuration information of the international prepaid phone card and the phone number that the user wishes to call pre-stored in the memory unit.
    Type: Application
    Filed: May 14, 2003
    Publication date: March 11, 2004
    Applicant: Sweetone Science Technology Inc.
    Inventor: Chung-Cheng Wang
  • Patent number: 6150892
    Abstract: A method and device for frequency synthesizing, in which the digital frequency synthesizer includes a clock pair having two similar ring-oscillators to separately generate a search frequency and an output frequency, a frequency tracking unit, and a clock controlling unit. The frequency-search method includes two stages: one stage is the coarse search stage based on the "Prune-and-Search", and other stage is the fine search stage based on the "fixed-step" algorithm. In order to determine which search scheme is used to search the target frequency and to determine the lock status, two cost functions for search and lock-in are derived. These two cost functions define the search threshold and the lock threshold, and these thresholds define the cost window and the lock window. If the frequency error is higher than both the search and lock thresholds, a coarse search is activated to estimate the correct frequency.
    Type: Grant
    Filed: October 30, 1998
    Date of Patent: November 21, 2000
    Assignee: TFL Lan Inc.
    Inventors: Chen-Yi Lee, Terng-Yin Hsu, Bai-Jue Shieh, Chung Cheng Wang
  • Patent number: 5821725
    Abstract: An electric current compensation circuit for use with a multiple-phase burshless motor to reduce ripples in the output torque is disclosed. It contains a plurality of electric current compensation loops each for a respective phase winding and each of the electric compensation loops contains: (a) a first input for receiving a line current from the driver; (b) a second input for receiving the compensation current from the motor sensor; (c) a forward rectifying circuit for forwardly rectifying the line current and the compensation current; (d) a reverse rectifying circuit for reversely rectifying the line current and the compensation current; and (e) a summation circuit for summing the forwardly rectified compensation current and the reversely rectified compensation current and outputting a synthetic current to a phase winding of the motor.
    Type: Grant
    Filed: October 16, 1996
    Date of Patent: October 13, 1998
    Assignee: Industrial Technology Research Institute
    Inventors: Chung-Cheng Wang, Jin-Chern Chiou, Shih-Tung Cheng