Patents Assigned to Holtek Semiconductor
  • Publication number: 20080042706
    Abstract: The provided delay lock loop delaying an input signal includes a quadrature generator, a voltage controller and a delay cell. The input signal is inputted into the quadrature generator and the delay cell. A phase-changing signal from the quadrature generator and a delay signal respectively from the delay cell are inputted into the voltage controller at the same time so that a control voltage inputted into the delay cell to control a delay time of the delay signal is generated. Also, the provided phase angle generator generates an output signal in an arbitrary phase.
    Type: Application
    Filed: June 11, 2007
    Publication date: February 21, 2008
    Applicant: HOLTEK SEMICONDUCTOR INC.
    Inventors: Chih-Wei Yang, Chien-Hsun Lee
  • Patent number: 7330802
    Abstract: A method for calibrating a parameter of an IC, using an external device so as to calibrate an analog control parameter of an internal analog circuit in the IC. The external device is used in a detecting mode so as to detect whether the analog control parameter is beyond a pre-determined range. If the analog control parameter is beyond the pre-determined range, the external device is used in a calibrating mode so as to obtain a calibrated value and the calibrated value is then written into the internal analog circuit in the IC. The external device is used for detection and calibration repeatedly until the analog control parameter is within the pre-determined range. When the analog control parameter is within the pre-determined range, the calibrated value is written into a non-volatile memory in the IC.
    Type: Grant
    Filed: October 2, 2006
    Date of Patent: February 12, 2008
    Assignee: Holtek Semiconductor Inc.
    Inventor: Chi-Ho Hsu
  • Publication number: 20080030307
    Abstract: A radio frequency identification (RFID) transponder is provided. The RFID transponder includes an LC resonant circuit having a first high frequency (HF) terminal and a second HF terminal, producing an AC signal, and transmitting a data; a full-wave rectifying circuit having a high voltage terminal, a low voltage terminal, a first terminal electrically connected to the first HF terminal, and a second terminal electrically connected to the second HF terminal, and rectifying the AC signal to a DC signal; and a first data modulating circuit having a third and a fourth terminals respectively electrically connected to the low voltage terminal and the second HF terminal, wherein the first data modulating circuit is coupled to a part of the full-wave rectifying circuit so that the transponder respectively transmits the data and is charged when the AC signal is respectively a negative AC signal and a positive AC signal.
    Type: Application
    Filed: March 9, 2007
    Publication date: February 7, 2008
    Applicant: HOLTEK SEMICONDUCTOR INC.
    Inventor: Chi-Bing Chen
  • Publication number: 20080006882
    Abstract: A spiral inductor with high quality factor for an integrated circuit (IC) is disclosed, in which the metal layers arranged under a spiral inductor layer are parallel-connected to each other by the use of interconnects so as to increase the thickness of the metal layer and thus effectively reduce the parasitic resistance of the spiral inductor. In a preferred aspect, the parasitic resistance of the spiral inductor is reduced by increasing the interconnects, used for connecting the spiral inductor layer and the metal layer arranged underneath the same. In another preferred aspect, an interconnect is formed under the spiral inductor layer while enabling the same to be disconnected from the metal layer directly under the spiral inductor layer, by which the quality factor of the spiral inductor is increased since the substantial sectional area of the spiral inductor layer is increased and thus the parasitic resistance of the spiral inductor is decreased.
    Type: Application
    Filed: August 29, 2006
    Publication date: January 10, 2008
    Applicant: HOLTEK SEMICONDUCTOR, INC.
    Inventor: Yung-Sheng Huang
  • Patent number: 7315216
    Abstract: An adjusting frequency device of built-in oscillator for USB interface and a method thereof are described. It is Auto detect the error of bit-rate between the USB host and the USB device, and produce tiny counting time for clocking the clock error between the USB host and the USB device by a delay lock loop. The clock error after quantification, digitization and operation outputting a quantitative code, then the oscillator adjusts the oscillation frequency according to the quantitative code. Whereby adjusting the oscillation frequency of the USB device and the frequency of the USB host to less than 1% clock error for ensuring the accuracy of data transmission.
    Type: Grant
    Filed: April 21, 2006
    Date of Patent: January 1, 2008
    Assignee: Holtek Semiconductor Inc.
    Inventors: Chih-Wei Yang, Chien-Hsun Lee, Hsiang-Sheng Liu, Juh-Gua Shiau
  • Patent number: 7312589
    Abstract: A driver control circuit and method for a cold cathode fluorescent lamp (CCFL), that the driver control circuit comprises: at least a comparator; at least an input/output port, at least an analog-to-digital converter; at least two programmable pulse generators (PPGs), including a first programmable pulse generator and a second programmable pulse generator, i.e. PPG0 and PPG1, being activated for generating pulse signals in an alternative manner for driving the CCFL; at least a programmable frequency divider (PFD), capable of programming the output thereof to be used as the control signal for activating the PPG0 and the PPG1 according to the alternative manner defined by the transition frequency of the PFD.
    Type: Grant
    Filed: January 25, 2006
    Date of Patent: December 25, 2007
    Assignee: Holtek Semiconductor
    Inventors: Yuan-Ho Liu, Chun-Hsiung Chen
  • Patent number: 7283000
    Abstract: An auto-adjusting high accuracy oscillator is disclosed, which includes: a frequency comparator, for comparing a synchronization signal obtained from a USB host with an oscillation signal obtain from a device; a control tuning circuit, further comprising a counter and an adder/sub circuit; and an oscillating element; wherein a variation is obtained by the counting of the counter while transmitting the variation to the adder/sub circuit to be encoded thereby into a digital code so as to enable the oscillating element to perform a frequency up/down operation accordingly for approaching the synchronization signal successively.
    Type: Grant
    Filed: December 2, 2005
    Date of Patent: October 16, 2007
    Assignee: Holtek Semiconductor
    Inventors: Chih Wei Yang, Chien Hsun Lee, Hsiang Sheng Liu, Quan Xing Huang
  • Patent number: 7271372
    Abstract: A power control apparatus for electric cookers includes an input unit, an output unit, a micro controller unit (MCU), having a programmer pulse generator (PPG) and at least an analog/digital converter built therein, a power circuit, an exciter-coil circuit, an output circuit of insulated gate bipolar transistor (IGBT), and a drive circuit of insulated gate bipolar transistor (IGBT). A command can be inputted externally to the MCU for restarting or stopping the output of the PPG and the PPG is capable of outputting pulses of programmable pulse width.
    Type: Grant
    Filed: August 10, 2005
    Date of Patent: September 18, 2007
    Assignee: Holtek Semiconductor
    Inventors: Yuan-Ho Liu, Chun-Hsiung Chen, Chun-Ku Lin
  • Publication number: 20070170961
    Abstract: Disclosed is an improved circuit and method for generating a power on reset signal, the circuit being a two-stage circuit comprising a delay-stage circuit and an output-stage circuit. The delay-stage circuit delays a time for a power on reset signal generated in the output-stage circuit changing from low to high, so that a power voltage having a low rising speed may be normally reset. Further, the two stages provide charging paths and discharging paths so that the power on reset signal may be prevented from changing from high to low when it has changed from low to high, when noises are presented on the power voltage.
    Type: Application
    Filed: March 2, 2006
    Publication date: July 26, 2007
    Applicant: Holtek Semiconductor Inc.
    Inventors: Chun-Yao Liao, Yu-Ren Chen
  • Publication number: 20070164801
    Abstract: Disclosed is a low hysteresis center offset comparator, comprising a first switch device, a differential amplifier, a second switch device, a general comparator, a first inverter and a second inverter. By means of the components, a hysteresis window with the low hysteresis center offset may be formed with respect to the inventive comparator with a width of a half-portion thereof formed equal to that of the other half-portion thereof corresponding to an offset voltage inherent in the differential amplifier.
    Type: Application
    Filed: March 22, 2006
    Publication date: July 19, 2007
    Applicant: Holtek Semiconductor Inc.
    Inventors: Yi-Chen Chen, Kevin Hsiao
  • Publication number: 20070165428
    Abstract: A digital pulse width modulation (DPWM) controlling system for controlling a load of an application circuit with a DPWM unit is provided, which comprises a comparator and a micro-control unit, the comparator receiving a sense signal detected from the load and a reference signal and comparing the sense signal and the reference signal to output an analog comparison signal, and the micro-control unit generating a trigger signal having a minimum pulse width and receiving the analog comparison signal to output a DPWM signal, wherein the micro-control unit adjusts the minimum pulse width of the trigger signal to obtain a pulse width of the DPWM signal in response to the analog comparison signal whenever the sense signal is within a stable duration so as to output the DPWM signal to the application circuit to control the load.
    Type: Application
    Filed: March 8, 2006
    Publication date: July 19, 2007
    Applicant: Holtek Semiconductor Inc.
    Inventors: Yi-Chan Lin, Yueh-Mei Hou, Chien-Feng Lai, Yi-Chen Liu
  • Publication number: 20070100616
    Abstract: A method for an audio algorithm is provided. The method includes steps of (a) providing an audio datum, a block division rule of unfixed sample size, and an encoding optimization process; (b) establishing a block from the audio datum by the block division rule of unfixed sample size; (c) obtaining an encoding result by encoding the block with the encoding optimization process; and (d) repeating respective steps (b)-(c) and thereby obtaining a plurality of the blocks.
    Type: Application
    Filed: October 24, 2006
    Publication date: May 3, 2007
    Applicant: HOLTEK SEMICONDUCTOR INC.
    Inventors: Min-Kun Wang, Chieh-Yung Tu
  • Publication number: 20070075986
    Abstract: A proximity sensing device for judging an operation is provided. The proximity sensing device includes a first sensing area sensing the operation and generating a first signal; and a second sensing area sensing the operation and generating a second signal, wherein if a ratio of the first signal and the second signal is greater than a threshold, the operation is judged as a correct operation.
    Type: Application
    Filed: October 3, 2006
    Publication date: April 5, 2007
    Applicant: Holtek Semiconductor Inc.
    Inventor: Chun-Hsiung Chen
  • Patent number: 7183869
    Abstract: In the present invention, a temperature compensation circuit is provided. The temperature compensation circuit includes a first oscillator for providing a first clock signal, a timer electrically connected to the first oscillator for clocking a specific time period, a voltage regulator for generating a constant voltage, a second oscillator electrically connected to the voltage regulator for providing a second clock signal, and a counter electrically connected to the second oscillator for counting within the specific time period based on the second clock signal so as to obtain a counting value, and thereby a frequency of the second oscillator is obtained for the temperature compensation.
    Type: Grant
    Filed: June 7, 2005
    Date of Patent: February 27, 2007
    Assignee: Holtek Semiconductor, Inc.
    Inventors: Kuo-Hsiang Chen, Chun-Ku Lin, Jason Chen
  • Patent number: 7138969
    Abstract: A method for sequentially driving light emitting diodes (LEDs) arranged in an array is provided. The method includes steps of a) electrically connecting anodes and cathodes of the LEDs to a ground; b) keeping the cathodes of a first part of the LEDs being electrically connected to the ground; c) increasing anode potentials of the LEDs to a first reference potential, and floating the cathodes of other parts of the LEDs simultaneously; d) supplying a current to the first part of the LEDs, and increasing cathode potentials of the other parts of the LEDs to a second reference potential simultaneously; and e) repeating the steps a)–d) for a second part of the LEDs. In which, the first part of the LEDs is arranged in a target row of the array and the second part of the LEDs is arranged in a row next to the target row.
    Type: Grant
    Filed: February 18, 2004
    Date of Patent: November 21, 2006
    Assignee: Holtek Semiconductor Inc.
    Inventors: Min Kun Wang, Shih Ting Chang
  • Publication number: 20060226245
    Abstract: An encoding format for a radio frequency identification system is provided. The encoding format includes a low-level pulse of one unit length and a high-level pulse of n unit length, wherein the value of n is adjusted to constitute different command/data formats.
    Type: Application
    Filed: March 14, 2006
    Publication date: October 12, 2006
    Applicant: Holtek Semiconductor Inc.
    Inventor: Chi-Ho Hsu
  • Publication number: 20060158276
    Abstract: In the present invention, a temperature compensation circuit is provided. The temperature compensation circuit includes a first oscillator for providing a first clock signal, a timer electrically connected to the first oscillator for clocking a specific time period, a voltage regulator for generating a constant voltage, a second oscillator electrically connected to the voltage regulator for providing a second clock signal, and a counter electrically connected to the second oscillator for counting within the specific time period based on the second clock signal so as to obtain a counting value, and thereby a frequency of the second oscillator is obtained for the temperature compensation.
    Type: Application
    Filed: June 7, 2005
    Publication date: July 20, 2006
    Applicant: Holtek Semiconductor Inc.
    Inventors: Kuo-Hsiang Chen, Chun-Ku Lin, Jason Chen
  • Publication number: 20060131428
    Abstract: A power processing interface for a radio frequency identification system is provided.
    Type: Application
    Filed: April 11, 2005
    Publication date: June 22, 2006
    Applicant: Holtek Semiconductor Inc.
    Inventors: Minkun Wang, Chun-Lin Shen, Chi-Ho Hsu, Chi-Bing Chen
  • Publication number: 20060114240
    Abstract: A controlling device for the cursor and the method for operating the same are provided. The controlling device includes a capacitor array having a plurality of equivalent capacitors, a microprocessor electrically connected to the capacitor array for sending a pulse train to the capacitor array in the x-direction and receiving a potential of each equivalent capacitor in the y-direction so as to determine a movement of a cursor, and a charge-absorbing device disposed above the capacitor array, wherein when the charge-absorbing device is moved correspondingly to a position of a specific equivalent capacitor in the capacitor array, a storage charge of the specific equivalent capacitor is absorbed so that the potential thereof is lowered, and thereby the movement of the cursor is determined by the microprocessor.
    Type: Application
    Filed: May 5, 2005
    Publication date: June 1, 2006
    Applicant: Holtek Semiconductor Inc.
    Inventor: Yi-Chan Lin
  • Publication number: 20060114241
    Abstract: An identification method for a touch control device having a memory and a pad electrically connected to an equivalent capacitance is provided. The provided identification method for a touch control device includes steps of: (a) charging the equivalent capacitance for obtaining a first voltage value; (b) storing the first voltage value in the memory; (c) touching the pad; (d) scanning the pad for obtaining a second voltage value of the equivalent capacitance; and (e) comparing the first voltage value with the second voltage of the equivalent capacitance for identifying a touched position on the pad.
    Type: Application
    Filed: June 8, 2005
    Publication date: June 1, 2006
    Applicant: Holtek Semiconductor Inc.
    Inventor: Yi-Chan Lin