Patents by Inventor Fu Tang

Fu Tang 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: 20120056683
    Abstract: An oscillator generates a clock signal according to a voltage, a current and a capacitance, and a frequency jitter circuit and method use a random number to modulate the voltage, the current or the capacitance, or a count value to modulate the capacitance, to jitter the frequency of the clock signal.
    Type: Application
    Filed: August 30, 2011
    Publication date: March 8, 2012
    Applicant: RICHTEK TECHNOLOGY CORP.
    Inventors: CHIEN-FU TANG, ISAAC Y. CHEN
  • Publication number: 20120008345
    Abstract: An apparatus and method for output voltage calibration of a primary feedback flyback power module extract the difference between the output voltage of the power module and a target value, and according thereto, calibrate a reference voltage which is used in regulation of the output voltage, to thereby calibrate the output voltage to be the target value.
    Type: Application
    Filed: June 30, 2011
    Publication date: January 12, 2012
    Applicant: RICHTEK TECHNOLOGY CORP.
    Inventors: CHIEN-FU TANG, ISAAC Y. CHEN, LIANG-PIN TAI
  • Publication number: 20110298436
    Abstract: The present invention discloses a control circuit of a switching regulator wherein a confirmation signal is generated to confirm that an upper gate switch has been turned off, to avoid shoot-through. The confirmation signal is generated by obtaining an upper gate sampling signal from a transistor in a level shift circuit which receives a resetting signal for turning off the upper gate switch.
    Type: Application
    Filed: November 10, 2010
    Publication date: December 8, 2011
    Inventors: Chien Fu Tang, Isaac Y. Chen, Pei-kai Tseng
  • Publication number: 20110233716
    Abstract: A circuit structure of an ultra high voltage level shifter includes a low voltage substrate having the electronic elements of the ultra high voltage level shifter thereon, an ultra high voltage redistribution layer, and a passivation layer between the substrate and the redistribution layer to prevent dielectric breakdown between the redistribution layer and the substrate.
    Type: Application
    Filed: March 15, 2011
    Publication date: September 29, 2011
    Applicant: RICHTEK TECHNOLOGY CORP.
    Inventors: CHIEN-FU TANG, ISAAC Y. CHEN
  • Publication number: 20110209512
    Abstract: A method for forming a metal article includes: heating a mold to a working temperature ranging from 350° C. to 550° C., the mold having a forming surface with a predetermined pattern; disposing a metal sheet in the mold that has been heated, the metal sheet being made from one of aluminum alloy and magnesium alloy and having a temperature not higher than 100° C.; and forming the metal sheet by applying a fluid-pressure of not less than 10 kg/cm2 into the mold to press the metal sheet against the predetermined pattern.
    Type: Application
    Filed: February 24, 2011
    Publication date: September 1, 2011
    Inventor: Fu-Tang LEE
  • Publication number: 20110187430
    Abstract: The present invention discloses a multi-chip module with master-slave analog signal transmission function. The multi-chip module comprises: a master chip having a first setting input pin for receiving an analog setting signal to generate an analog setting in the master chip, and the master chip duplicating the analog setting to output a first analog output; and a first slave chip for receiving the first analog output from the master chip to generate an internal setting of the first slave chip.
    Type: Application
    Filed: February 4, 2010
    Publication date: August 4, 2011
    Inventors: Chien Fu Tang, Isaac Y. Chen
  • Publication number: 20110109291
    Abstract: A non-constant frequency voltage regulator includes a constant-time trigger to trigger a constant on-time or a constant off-time for a pulse width modulation signal, a current generator to provide a first current to determine the constant on-time or the constant off-time, a power output stage operated by the pulse width modulation signal to produce a load current, and a frequency control circuit for loading feed forward by a second current added to the first current to adjust the constant on-time or the constant off-time for frequency compensation to the pulse width modulation signal.
    Type: Application
    Filed: November 9, 2010
    Publication date: May 12, 2011
    Applicant: RICHTEK TECHNOLOGY CORP.
    Inventors: CHIEN-FU TANG, ISAAC Y. CHEN
  • Publication number: 20110109238
    Abstract: The present invention discloses a digital dimming device and a digital dimming method, for controlling a plurality of light emitting device channels. The method comprises: generating a corresponding plurality of driving signals to control the plurality of light emitting device channels; receiving a PWM input signal having a duty ratio, and phase shifting the PWM input signal to generate multiple PWM output signals with about the same duty ratio as the PWM input signal, but with respectively shifted phases; and enabling or disabling corresponding driving signals by the multiple PWM output signals, respectively.
    Type: Application
    Filed: October 22, 2010
    Publication date: May 12, 2011
    Inventors: Chien-Fu Tang, Isaac Chen, An-Tung Chen
  • Publication number: 20110109290
    Abstract: A non-constant frequency voltage regulator includes a constant-time trigger to generate a pulse width modulation signal, a current generator to provide a first current to set a constant on-time or a constant off-time for the pulse width modulation signal, and a frequency control circuit to detect the pulse width of a phase node voltage, compare the pulse width with the constant on-time or the constant off-time set by the first current to generate a second current, and add the second current to the first current to supply to the constant-time trigger to control the frequency of the pulse width modulation signal.
    Type: Application
    Filed: November 9, 2010
    Publication date: May 12, 2011
    Applicant: RICHTEK TECHNOLOGY CORP.
    Inventors: CHIEN-FU TANG, ISAAC Y. CHEN
  • Publication number: 20110109398
    Abstract: A fixed-frequency control circuit and method detect the difference between the frequency of a pulse width modulation signal and a target frequency to adjust a current used to determine the on-time or off-time of the pulse width modulation signal, such that the frequency of the pulse width modulation signal is stable at the target frequency.
    Type: Application
    Filed: November 9, 2010
    Publication date: May 12, 2011
    Applicant: RICHTEK TECHNOLOGY CORP.
    Inventors: CHIEN-FU TANG, ISAAC Y. CHEN
  • Publication number: 20110068761
    Abstract: The present invention discloses an average current regulator, a driver circuit of an average current regulator, and a method for regulating an average current. The average current regulator includes: a power stage including at least one power transistor which switches according to a pulse width modulation (PWM) signal to convert an input voltage to an output current; a feedback circuit coupled to the power stage, for generating a feedback signal; an ON-time controller coupled to the feedback circuit, for receiving the feedback signal and generating an ON-time signal according to the feedback signal and an average reference signal relating to a target average current; and a PWM controller, for generating the PWM signal according to the ON-time signal to regulate the average of the output current to the target average current.
    Type: Application
    Filed: September 9, 2010
    Publication date: March 24, 2011
    Inventors: An-Tung Chen, Isaac Y. Chen, Chien-Fu Tang
  • Publication number: 20100320844
    Abstract: A power off delay circuit includes a switch connected between an external power input terminal and an internal power supply terminal, a capacitor connected to the internal power supply terminal, and a hysteresis comparator to switch the switch according to the voltages of the external power input terminal and the internal power supply terminal. During on-time of the switch, the external power input terminal is connected to the internal power supply terminal and the capacitor can be charged by the external power source. When the switch is off, the capacitor provides electric power for an internal circuit. Application of the power off delay circuit to an audio system may eliminate the turn-off pops of the audio system.
    Type: Application
    Filed: June 18, 2010
    Publication date: December 23, 2010
    Applicant: RICHTEK TECHNOLOGY CORP.
    Inventors: CHI-HUA LIN, CHIEN-FU TANG, ISAAC Y. CHEN, AN-TUNG CHEN
  • Publication number: 20100321849
    Abstract: An overstress protection apparatus includes a switch detector. The switch is arranged in a grounding path of a load system. The detector detects the current, voltage or temperature of the load system to determine a signal for controlling the switch, to thereby protect the load system working in normal conditions.
    Type: Application
    Filed: June 15, 2010
    Publication date: December 23, 2010
    Applicant: RICHTEK TECHNOLOGY CORP.
    Inventors: CHIEN-FU TANG, ISAAC Y. CHEN, CHI-HUA LIN
  • Patent number: 7800425
    Abstract: An on-chip mode-setting circuit and method are provided for a chip having an output driver with an output terminal connected to a pin of the chip. The pin may be defined between two states from exterior of the chip. The on-chip mode-setting circuit includes an electronic element connected to a bias input of the output driver for producing a voltage when the pin is defined at one of the two states, and a voltage detector for monitoring the voltage to determine which one of the two states the pin is at, and producing a mode-setting signal accordingly.
    Type: Grant
    Filed: November 20, 2007
    Date of Patent: September 21, 2010
    Assignee: Richtek Technology Corp.
    Inventors: Chien-Fu Tang, Isaac Y. Chen
  • Patent number: 7795755
    Abstract: A power converter system includes multiple converter modules connected to a share bus. Each of the converter modules mirrors the phase current of itself to provide a mirror current to the share bus, extracts an average current from the share bus, and compares the phase current of itself with the average current it extracts from the share bus to produce an output signal for modulation of the phase current of itself. Specifically, each of the converter modules is provided with a resistor connected to the share bus such that all the resistors are connected in parallel, and thus each of the resistors automatically receives an average current from the share bus.
    Type: Grant
    Filed: August 6, 2008
    Date of Patent: September 14, 2010
    Assignee: Richtek Technology Corp.
    Inventors: Isaac Y. Chen, Chien-Fu Tang
  • Publication number: 20100209336
    Abstract: A nanostructure includes a plurality of metal nanoblades positioned with one edge on a substrate. Each of the plurality of metal nanoblades has a large surface area to mass ratio and a width smaller than a length. A method of storing hydrogen includes coating a plurality of magnesium nanoblades with a hydrogen storage catalyst and storing hydrogen by chemically forming magnesium hydride with the plurality of magnesium nanoblades.
    Type: Application
    Filed: March 26, 2008
    Publication date: August 19, 2010
    Inventors: Toh-Ming Lu, Gwo-Ching Wang, Fu Tang, Thomas Parker
  • Patent number: 7749866
    Abstract: A method for sawing a wafer includes the following steps. A wafer which has an active surface, a back surface and a plurality of longitudinal and transverse sawing lines is provided, wherein the sawing lines are located on the active surface so as to define a plurality of dies. A multiple-type tape is attached on the active surface of the wafer, wherein the multiple-type tape includes a first tape and a second tape, the second tape is located between the first tape and the active surface of the wafer, and the second tape is transparent. The back surface of the wafer is grinded. The first tape is removed. Finally, the wafer including the second tape is sawn along the sawing lines so as to separate the dies from one another.
    Type: Grant
    Filed: January 22, 2008
    Date of Patent: July 6, 2010
    Assignee: Advanced Semiconductor Engineering, Inc.
    Inventors: Fu Tang Chu, Chi Yuam Chung
  • Publication number: 20100053951
    Abstract: An LED floor lamp comprises a main structure, a light shade and a light source, the main structure includes a rod and a base, and the light shade includes a reflecting surface, wherein the rod is fixed on the base, the light shade is mounted on a top end of the rod and the reflecting surface thereof faces upward, the light source is disposed in the light shade and consisted of a plurality of single-packaged light emitting diodes each with a power of more than 12 W. Therefore, the LED floor lamp can provide a high illumination while avoiding energy waste.
    Type: Application
    Filed: September 4, 2008
    Publication date: March 4, 2010
    Inventors: Te-Hsuan HSIEH, Yung-Fu TANG
  • Publication number: 20100000423
    Abstract: A peeling apparatus includes a peel body and a ceramic blade unit. The peel body has a handgrip part and two carrier arms extending from a distal end of the handgrip part. The ceramic blade unit has two opposite sides connected pivotally to the carrier arms, an inner cutting edge and an outer blunt edge extending between the opposite sides so as to expose the outer blunt edge to an exterior thereof. The inner cutting edge is used for peeling an external surface of fruit and vegetable, and the outer blunt edge is easy shoveled off waste resulted from peeling operation of the inner cutting edge.
    Type: Application
    Filed: August 8, 2008
    Publication date: January 7, 2010
    Inventors: MING-TUNG YU, FU-TANG LIN
  • Patent number: 7576522
    Abstract: For soft start of a switching regulator, the output voltage of the switching regulator is fed back to be compared with a ramp signal, in order to trigger a comparison signal when the ramp signal rises up to reach the feedback signal, to enable the switching regulator such that the output voltage changes from a residual voltage toward a target value. The low side switch of the switching regulator is kept off for a period of time after the switching regulator is enabled, so as to prevent a reverse current during the soft start period.
    Type: Grant
    Filed: March 24, 2008
    Date of Patent: August 18, 2009
    Assignee: Richtek Technology Corp.
    Inventors: Isaac Y. Chen, Chien-Fu Tang