Patents by Inventor Jwin-Yen Guo
Jwin-Yen Guo 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).
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Patent number: 8755539Abstract: An electrostatic transducer loudspeaker includes a filterless class-D amplifier to modulate an audio input signal to generate a modulated signal containing a PWM switching carrier component, and a transformer directly connected at an output side of the filterless class-D amplifier and directly connected at an input side of an electrostatic transducer, whereby the equivalent capacitance of the electrostatic transducer and the equivalent inductance of the transformer establish a resonance circuit to demodulate the modulated signal to generate an AC voltage to drive the electrostatic transducer.Type: GrantFiled: November 16, 2010Date of Patent: June 17, 2014Assignee: Richtek Technology Corp.Inventors: Pei-Cheng Huang, Jwin-Yen Guo
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Patent number: 8487690Abstract: A dual mode charge pump is operable in a first mode or a second mode for providing positive and negative output voltages that can be stabilized by adjusting the charging time of two terminals of a flying capacitor or by adjusting the charging/discharging time of the positive and negative voltage output terminals. The dual mode charge pump can apply to a much wider input supply voltage range with less numbers of power switches, thus requiring less die area and lower costs. Moreover, the dual mode charge pump can precisely define a common mode voltage, thus making the common voltage drift smaller and less load dependent, especially when the output supply voltages are under different load conditions.Type: GrantFiled: March 30, 2012Date of Patent: July 16, 2013Assignee: Richtek Technology Corp.Inventors: Wei-Hsin Wei, Jwin-Yen Guo, Teng-Hung Chang, Ming-Jun Hsiao
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Patent number: 8411879Abstract: A speaker driver circuit driven by positive and negative voltages, comprising: at least one operational amplifier providing an output to a headphone speaker, and a voltage converter receiving a supplied voltage (VDD), generating r-fold positive and negative voltages (r·VDD and ?r·VDD, wherein r is any positive real number except 1) according to the supplied voltage, and supplying the positive and negative voltages to the operational amplifier for its high and low operation voltage levels respectively.Type: GrantFiled: July 21, 2009Date of Patent: April 2, 2013Assignee: Richtek Technology CorporationInventors: Jwin-Yen Guo, Ching-Hsiang Yang
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Patent number: 8310313Abstract: A highly efficient class-G amplifier includes an amplifier circuit coupled between a positive power rail and a negative power rail to amplify an audio input signal of the class-G amplifier, and a boost inverting power converter to convert a supply voltage to a positive rail voltage and a negative rail voltage on the positive and negative power rails. The boost inverting power converter includes a boost inverting power stage coupled to the positive and negative power rails, and a controller to switch the boost inverting power stage between a boost mode and an inverting mode. An audio level detector detects the audio input signal for the controller to adjust the positive and negative rail voltages. The class-G amplifier has higher efficiency and requires lower cost because it does not need a charge pump.Type: GrantFiled: October 6, 2010Date of Patent: November 13, 2012Assignee: Richtek Technology Corp.Inventors: Jwin-Yen Guo, Tsung-Nan Wu
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Publication number: 20120249224Abstract: A dual mode charge pump is operable in a first mode or a second mode for providing positive and negative output voltages that can be stabilized by adjusting the charging time of two terminals of a flying capacitor or by adjusting the charging/discharging time of the positive and negative voltage output terminals. The dual mode charge pump can apply to a much wider input supply voltage range with less numbers of power switches, thus requiring less die area and lower costs. Moreover, the dual mode charge pump can precisely define a common mode voltage, thus making the common voltage drift smaller and less load dependent, especially when the output supply voltages are under different load conditions.Type: ApplicationFiled: March 30, 2012Publication date: October 4, 2012Applicant: Richtek Technology CorporationInventors: Wei-Hsin WEI, Jwin-Yen GUO, Teng-Hung CHANG, Ming-Jun HSIAO
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Patent number: 8159294Abstract: The present invention discloses a multi-voltage headphone driver circuit comprising: at least one operational amplifier having an output supplied to a headphone speaker, the operational amplifier receiving a first power supply as its high operation voltage; a charge pump receiving a second power supply to generate a negative voltage corresponding to the second power supply in magnitude; and an m-fold circuit multiplying the negative voltage by m and providing the result to the operational amplifier as a low operation voltage thereof, wherein m is a real number.Type: GrantFiled: July 21, 2009Date of Patent: April 17, 2012Assignee: Richtek Technology CorporatonInventors: Jwin-Yen Guo, Ching-Hsiang Yang
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Patent number: 8115542Abstract: A class-D amplifier includes a ramp generator to provide a ramp signal having a frequency varying with an audio input signal, and a modulator to convert the audio input signal to a pulse width modulation signal according to the ramp signal for a driver to drive a load device. The varying frequency of the ramp signal will cause the frequency of the pulse width modulation signal unfixed and consequently improves EMI issue.Type: GrantFiled: August 17, 2010Date of Patent: February 14, 2012Assignee: Richtek Technology Corp.Inventors: Pei-Cheng Huang, Jwin-Yen Guo, Shao-Ming Sun
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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: 8018280Abstract: A class-D audio amplifier is protected by thermal regulation which decreases the gain of the class-D audio amplifier by asserting an over-temperature signal when the temperature of the class-D audio amplifier is detected to be higher than a threshold. The output of the class-D audio amplifier is therefore reduced by the smaller gain, and the chance for the class-D audio amplifier to stop working due to overheating is greatly reduced.Type: GrantFiled: November 5, 2009Date of Patent: September 13, 2011Assignee: Richtek Technology Corp.Inventors: Chun-Tsung Chen, Jwin-Yen Guo, Chung-Fu Wang
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Publication number: 20110116657Abstract: An electrostatic transducer loudspeaker includes a filterless class-D amplifier to modulate an audio input signal to generate a modulated signal containing a PWM switching carrier component, and a transformer directly connected at an output side of the filterless class-D amplifier and directly connected at an input side of an electrostatic transducer, whereby the equivalent capacitance of the electrostatic transducer and the equivalent inductance of the transformer establish a resonance circuit to demodulate the modulated signal to generate an AC voltage to drive the electrostatic transducer.Type: ApplicationFiled: November 16, 2010Publication date: May 19, 2011Applicant: RICHTEK TECHNOLOGY CORP.Inventors: PEI-CHENG HUANG, JWIN-YEN GUO
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Patent number: 7944289Abstract: For minimum pulse generation in a class-D amplifier, a trapezoid switching waveform shape is used to replace the tradition triangle type to generate PWM pulses. Two voltages are compared with a sawtooth wave signal to generate the trapezoid waveform signal and a constant pulse width signal. An audio input signal is compared with the trapezoid waveform signal to generate a pulse width modulation signal, and either the pulse width modulation signal or the constant pulse width signal is used for driving a load at an output of the class-D amplifier. Flexible minimum pulse width could be obtained by offsetting one of the two voltages in generation of the constant pulse width signal.Type: GrantFiled: September 29, 2009Date of Patent: May 17, 2011Assignee: Richtek Technology Corp.Inventors: Pei-Cheng Huang, Jwin-Yen Guo
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Publication number: 20110084760Abstract: A highly efficient class-G amplifier includes an amplifier circuit coupled between a positive power rail and a negative power rail to amplify an audio input signal of the class-G amplifier, and a boost inverting power converter to convert a supply voltage to a positive rail voltage and a negative rail voltage on the positive and negative power rails. The boost inverting power converter includes a boost inverting power stage coupled to the positive and negative power rails, and a controller to switch the boost inverting power stage between a boost mode and an inverting mode. An audio level detector detects the audio input signal for the controller to adjust the positive and negative rail voltages. The class-G amplifier has higher efficiency and requires lower cost because it does not need a charge pump.Type: ApplicationFiled: October 6, 2010Publication date: April 14, 2011Applicant: RICHTEK TECHNOLOGY CORP.Inventors: JWIN-YEN GUO, TSUNG-NAN WU
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Patent number: 7911267Abstract: A sigma-delta class-D amplifier includes a quantizer to quantize an input to produce a digital signal, and an output stage to produce an output according to the digital signal. The quantizer has a smaller step size so that the digital signal has at least five logical levels, and the sigma-delta class-D amplifier is thus improved to have wider stable modulation range and less switching loss.Type: GrantFiled: September 3, 2008Date of Patent: March 22, 2011Assignee: Richtek Technology Corp.Inventors: Teng-Hung Chang, Jwin-Yen Guo
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Patent number: 7911273Abstract: A switching amplifier has a network including current sources and resistors connected to the two output terminals of the H-bridge of the switching amplifier, to provide a small current to the load connected between the two output terminals at zero input, whereby the common mode voltage bouncing is reduced and the switching amplifier has less power consumption and reduced electro-magnetic interference.Type: GrantFiled: March 24, 2009Date of Patent: March 22, 2011Assignee: Richtek Technology Corp.Inventors: Jing-Meng Liu, Jwin-Yen Guo, Shao-Ming Sun
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Apparatus and method for improving the feedback linearity of a 1.5-bit sigma-delta class-D amplifier
Patent number: 7911268Abstract: A conversion circuit is provided for a 1.5-bit ?-? class-D amplifier to improve the feedback linearity of the class-D amplifier, by periodically inverting and mixing a first positive feedback signal and a first negative feedback signal from the power stage of the class-D amplifier to generate a second positive feedback signal and a second negative feedback signal with better linearity for feedback control in the class-D amplifier.Type: GrantFiled: January 6, 2009Date of Patent: March 22, 2011Assignee: Richtek Technology Corp.Inventors: Teng-Hung Chang, Jwin-Yen Guo -
Publication number: 20110043283Abstract: A class-D amplifier includes a ramp generator to provide a ramp signal having a frequency varying with an audio input signal, and a modulator to convert the audio input signal to a pulse width modulation signal according to the ramp signal for a driver to drive a load device. The varying frequency of the ramp signal will cause the frequency of the pulse width modulation signal unfixed and consequently improves EMI issue.Type: ApplicationFiled: August 17, 2010Publication date: February 24, 2011Applicant: RICHTEK TECHNOLOGY CORP.Inventors: PEI-CHUNG HUANG, JWIN-YEN GUO, SHAO-MING SUN
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Patent number: 7839667Abstract: In an adaptive leading-edge blanking circuit and method for a switching mode power converter, an inductor current of the converter is sensed and compared with a threshold to decide an end point of a leading-edge blanking time. Circuit and method are further provided for preventing the converter from entering pulse skipping mode, which employs a current trimming circuit in an oscillator for a PWM controller in the converter to reduce a charging current in the oscillator if the output voltage of the converter is excessively high, to thereby reduce the oscillator frequency and in turn lower the switching frequency of a high-side power switch of the converter.Type: GrantFiled: February 26, 2008Date of Patent: November 23, 2010Assignee: Richtek Technology Corp.Inventors: Chia-Wei Liao, Jing-Meng Liu, Jwin-Yen Guo
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Patent number: 7741902Abstract: In a class-D amplifier, the input signal is compared with a carrier signal to generate a basic PWM signal, the PWM signal is then sent to a pulse processing unit, and by comparing with a basic periodic signal, half-width of the output PWM signal is extracted. Then, in the pulse processing unit, the half-width PWM pulse signal is used to generate a complete pulse whose width equals to the output PWM signal. The output power of the class-D amplifier can be kept as large as that by using differential input signals although the input signal is single-end and the entire signal processing path is kept single-ended.Type: GrantFiled: October 14, 2008Date of Patent: June 22, 2010Assignee: Richtek Technology CorporationInventors: Jwin-Yen Guo, Shao-Ming Sun
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Publication number: 20100117731Abstract: A class-D audio amplifier is protected by thermal regulation which decreases the gain of the class-D audio amplifier by asserting an over-temperature signal when the temperature of the class-D audio amplifier is detected to be higher than a threshold. The output of the class-D audio amplifier is therefore reduced by the smaller gain, and the chance for the class-D audio amplifier to stop working due to overheating is greatly reduced.Type: ApplicationFiled: November 5, 2009Publication date: May 13, 2010Inventors: Chun-Tsung Chen, Jwin-Yen Guo, Chung-Fu Wang
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Publication number: 20100079208Abstract: For minimum pulse generation in a class-D amplifier, a trapezoid switching waveform shape is used to replace the tradition triangle type to generate PWM pulses. Two voltages are compared with a sawtooth wave signal to generate the trapezoid waveform signal and a constant pulse width signal. An audio input signal is compared with the trapezoid waveform signal to generate a pulse width modulation signal, and either the pulse width modulation signal or the constant pulse width signal is used for driving a load at an output of the class-D amplifier. Flexible minimum pulse width could be obtained by offsetting one of the two voltages in generation of the constant pulse width signal.Type: ApplicationFiled: September 29, 2009Publication date: April 1, 2010Inventors: Pei-Cheng Huang, Jwin-Yen Guo