Patents Assigned to Richtek Technology Corporation, R.O.C.
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Patent number: 8320149Abstract: 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: GrantFiled: February 4, 2010Date of Patent: November 27, 2012Assignee: Richtek Technology Corporation, R.O.C.Inventors: Chien Fu Tang, Isaac Y. Chen
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Patent number: 8319444Abstract: The present invention discloses a tail-less LED control circuit, which includes: a power supply stage having an output terminal which provides electrical power to an LED circuit; an output capacitor coupled to the output terminal; an LED driver circuit coupled to the power supply stage for controlling the power supply stage to provide the electrical power to the LED circuit, the LED driver circuit receiving a PWM dimming signal for adjusting brightness of the LED circuit; and a MOSFET switch coupled to the output capacitor in series, the MOSFET switch switching synchronously with the PWM dimming signal to alleviate LED afterglow, wherein the MOSFET switch includes a body diode having an anode-cathode direction against the discharge direction of the output capacitor.Type: GrantFiled: May 26, 2010Date of Patent: November 27, 2012Assignee: Richtek Technology Corporation, R.O.C.Inventors: Chiawei Liao, Jing-Meng Liu, Leng-Nien Hsiu
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Patent number: 8258752Abstract: The present invention discloses an integrated PMOS transistor and Schottky diode, comprising a PMOS transistor which includes a gate, a source, a drain and a channel region between the source and drain, wherein the source, drain and channel region are formed in a substrate, and a parasitic diode is formed between the drain and the channel region; and a Schottky diode formed in the substrate and connected in reverse series with the parasitic diode, the Schottky diode having one end connected with the parasitic diode and the other end connected with the source.Type: GrantFiled: December 3, 2009Date of Patent: September 4, 2012Assignees: Richpower Microelectronics Corporation, Richtek Technology Corporation, R.O.C.Inventors: Kuo-Chin Chiu, Chih-Feng Huang
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Patent number: 8258714Abstract: The present invention discloses an LED controller with phase-shift dimming function and an LED Phase-Shift dimming circuit and method thereof. The LED controller includes: a power circuit for supplying DC power to multiple LED channels; and an LED phase-shift dimming circuit for receiving a pulse width modulation (PWM) input signal and generating multiple phase-shifted PWM signals with a shifted phase between one another, wherein a turn-ON timing of each of the multiple phase-shifted PWM signals follows a turn-OFF timing of a previous PWM signal which is the input PWM signal or a previous one of the multiple phase-shifted PWM signals.Type: GrantFiled: April 27, 2010Date of Patent: September 4, 2012Assignee: Richtek Technology Corporation, R.O.C.Inventor: Jing-Meng Liu
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Patent number: 8248000Abstract: The present invention discloses a light emitting device array controller which controls a power stage to supply an output voltage to one end of each of a plurality of light emitting device strings. The other end of each of the light emitting device strings is coupled to a corresponding transistor having a current inflow end, a current outflow end and a control end. The present invention obtains signals from the control ends of the transistors instead of the current inflow ends, and feedback controls the output voltage according to the highest voltage of the control ends. Thus, the number of pins required for a circuit chip is reduced.Type: GrantFiled: May 26, 2010Date of Patent: August 21, 2012Assignee: Richtek Technology Corporation, R.O.C.Inventor: Jing-Meng Liu
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Patent number: 8179059Abstract: The present invention discloses a circuit and a method for controlling a light emitting device, and an integrated circuit therefore. The circuit for controlling a light emitting device comprises: a power stage controller circuit controlling a power stage circuit to convert an input voltage to an output voltage, which is supplied to at least one light emitting device channel including at least one light emitting device; a transistor switch in the light emitting device channel; and a current source circuit controlling a current through the light emitting device channel, wherein the power stage controller circuit and the current source circuit are integrated in an integrated circuit which provides a control voltage to control a gate of the transistor switch.Type: GrantFiled: October 15, 2009Date of Patent: May 15, 2012Assignee: Richtek Technology Corporation, R.O.C.Inventors: Chih-Hao Yang, Fu-Yuan Shih, An-Tung Chen, Shui-Mu Lin
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Patent number: 8143130Abstract: The present invention discloses a method of manufacturing a depletion metal oxide semiconductor (MOS) device. The method includes: providing a substrate; forming a first conductive type well and an isolation region in the substrate to define a device area; defining a drift region, a source, a drain, and a threshold voltage adjustment region, and implanting second conductive type impurities to form the drift region, the source, the drain, and the threshold voltage adjustment region, respectively; defining a breakdown protection region between the drain and the threshold voltage adjustment region, and implanting first conductive type impurities to form the breakdown protection region; and forming a gate in the device area; wherein a part of the breakdown protection region is below the gate, and the breakdown protection region covers an edge of the threshold voltage adjustment region.Type: GrantFiled: October 22, 2010Date of Patent: March 27, 2012Assignee: Richtek Technology Corporation, R.O.C.Inventor: Tsung-Yi Huang
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Patent number: 8140726Abstract: The present invention discloses a single wire transmission interface comprising: a signal detection circuit detecting level switchings of a transmission signal from a single wire, and generating an enable signal and a decoded signal corresponding to the transmission signal, the level switchings including first switchings from a first level to a second level and second switchings from the second level to the first level, wherein the enable signal starts according to one first switching of the transmission signal, and stops when no first switching occur in a predetermined period after one second switching of the transmission signal, and wherein rising edges (or falling edges) of the decoded signal correspond to the first switchings of the transmission signal; a counter, under enablement by the enable signal, counting a number of the rising edges (or the rising edges) of the decoded signal or the first switchings of the transmission signal, and generating a count; a single short pulse generator generating a shorType: GrantFiled: October 23, 2009Date of Patent: March 20, 2012Assignee: Richtek Technology Corporation, R.O.C.Inventors: Nien-Hui Kung, Kwan-Jen Chu
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Patent number: 8134353Abstract: The present invention discloses a multi-phase power converter, and a control circuit and a control method of the multi-phase power converter. The multi-phase power converter comprises multiple power conversion phases. The method comprises: determining whether to enter a phase-shedding mode; at a first time when entering the phase-shedding mode, disabling at least one of the power conversion phases; and at another time when entering the phase-shedding mode, disabling at least another one of the power conversion phases.Type: GrantFiled: July 2, 2009Date of Patent: March 13, 2012Assignee: Richtek Technology Corporation, R.O.C.Inventors: Ching-Jan Chen, Chun-Shih Huang, Kuo-Lung Tseng, Dan Chen
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Patent number: 8072153Abstract: The present invention discloses a multi-color backlight control circuit, comprising: a plurality of pins for electrically connecting with a plurality of LED strings of different LED colors; and a voltage supply circuit for receiving an input voltage and supplying a single output voltage to the plurality of LED strings of different LED colors. The present invention also discloses a multi-color backlight control method, comprising: supplying a single output voltage to a plurality of LED strings of different LED colors.Type: GrantFiled: January 11, 2011Date of Patent: December 6, 2011Assignee: Richtek Technology Corporation R.O.C.Inventor: Jing-Meng Liu
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Patent number: 8064620Abstract: The present invention discloses a driver circuit for an electrostatic loudspeaker, comprising: a digital modulation encoder for receiving a digital audio signal and a fixed frequency pulse signal, and mixing them by modulation; a digital to analog converter for converting the output of the digital modulation encoder to an analog signal; a transformer for adjusting the voltage amplitude of the analog signal; and a demodulator for demodulating the adjusted analog signal to driver a speaker.Type: GrantFiled: August 22, 2008Date of Patent: November 22, 2011Assignee: Richtek Technology Corporation, R.O.C.Inventors: Pei-Cheng Huang, Jwin-Yen Guo, Kuo-Chi Liu
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Patent number: 8049462Abstract: The present invention discloses a universal serial bus (USB) charging circuit, comprising: a charging path for charging a battery from a USB host; a charging switch located on the charging path; a current sensing circuit for sensing current information on the charging path; a maximum available current detection circuit for detecting the maximum available current from the USB host; and a loop controller circuit for controlling the charging switch so that the charging current on the charging path is substantially equal to the maximum available current detected by the maximum available current detection circuit, wherein the maximum available current detection circuit detects the maximum available current during circuit initialization and stores it.Type: GrantFiled: September 18, 2008Date of Patent: November 1, 2011Assignee: Richtek Technology Corporation, R.O.C.Inventors: Nien-Hui Kung, Kwan-Jen Chu, Jing-Meng Liu
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Patent number: 8026676Abstract: The present invention discloses a dimming control circuit, comprising: an input terminal for receiving an input signal; an analog and digital dimming circuit receiving the input signal, wherein the analog and digital dimming circuit provides an analog dimming function when a voltage level of the input signal is between a predetermined lower limit and a predetermined upper limit, and a digital dimming function when the voltage level of the input signal switches above and below the predetermined lower limit, and wherein the analog and digital dimming circuit generates an analog signal when the voltage level of the input signal is above the predetermined lower limit; and a power circuit for supplying an output current in correspondence to the analog signal generated by the analog and digital dimming circuit.Type: GrantFiled: December 4, 2008Date of Patent: September 27, 2011Assignee: Richtek Technology Corporation, R.O.C.Inventors: Jing-Meng Liu, Chiawei Liao, Leng-Nien Hsiu
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Patent number: 7943994Abstract: The present invention discloses an integrated PMOS transistor and Schottky diode, comprising a PMOS transistor which includes a gate, a source, a drain and a channel region between the source and drain, wherein the source, drain and channel region are formed in a substrate, and a parasitic diode is formed between the drain and the channel region; and a Schottky diode formed in the substrate and connected in reverse series with the parasitic diode, the Schottky diode having one end connected with the parasitic diode and the other end connected with the source.Type: GrantFiled: May 22, 2009Date of Patent: May 17, 2011Assignee: Richtek Technology Corporation, R.O.C.Inventor: Chih-Feng Huang
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Patent number: 7728628Abstract: The present invention discloses a level shift circuit which comprises: a basic level shift circuit for receiving inputs of first high and low operational voltage levels and generating outputs of second low and high operational voltage levels at a first node; and an output circuit for outputting a signal of one of the second operational voltage levels according to a voltage level switching at the first node.Type: GrantFiled: November 2, 2008Date of Patent: June 1, 2010Assignee: Richtek Technology Corporation, R.O.C.Inventor: Yun-Chi Chiang
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Patent number: 7728571Abstract: The present invention discloses a load-dependent frequency jittering circuit, comprising: a load condition detection circuit for receiving a switching signal and generating an output according to a load condition; a number generator for receiving the output of the load condition detection circuit and generating a number; a digital to analog converter for converting the output of the number generator to an analog signal; and an oscillator for generating a jittered frequency according to the output of the digital to analog converter.Type: GrantFiled: November 6, 2007Date of Patent: June 1, 2010Assignee: Richtek Technology Corporation, R.O.C.Inventors: Chao-Hsuan Chuang, Cheng-Hsuan Fan, Hung-Che Chou, Ching-Hsiang Yang
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Patent number: 7728529Abstract: In a LED driver using a depletion mode transistor to serve as a current source, the depletion mode transistor is self-biased for providing a driving current to drive at least one LED, thereby requesting no additional control circuit to control the depletion mode transistor. The driving current is independent on the supply voltage coupled to the at least one LED, thereby requesting no additional voltage regulator, reducing the circuit size, and lowering the cost.Type: GrantFiled: June 10, 2005Date of Patent: June 1, 2010Assignee: Richtek Technology Corporation, R.O.C.Inventors: Jing-Meng Liu, Chung-Lung Pai, Hung-Der Su