Patents by Inventor Rawinder Dharmalinggam
Rawinder Dharmalinggam 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: 11757359Abstract: An improved power converter produces power through a power switch in response to an activation signal that has an on-time and a switching frequency. An on-time signal has a constant on-time and controls the on-time of the activation signal. An error signal indicates that the switching frequency is not equal to a reference frequency. A step up signal and a step down signal are based on the error signal. A count signal is increased in response to the step up signal and decreased in response to the step down signal. An on-time pulse has a duration that is related to a value of the count signal. The on-time pulse controls the constant on-time of the on-time signal and maintains the switching frequency at about the reference frequency.Type: GrantFiled: September 13, 2022Date of Patent: September 12, 2023Assignee: Silanna Asia Pte LtdInventors: Rawinder Dharmalinggam, Tiong Lim
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Patent number: 11664719Abstract: During a first mode of operation, a zero current detect (ZCD) signal is asserted in response to detecting a zero current condition at a switch node of a power converter. The power converter enters a light load mode of operation when the ZCD signal is asserted between a beginning point and a trigger point of a period of a PWM signal. A compensator voltage is generated based on a feedback voltage indicative of an output voltage. The compensator voltage is compared to a threshold voltage that represents a limit for the compensator voltage during the light load mode of operation determined over a range of the output voltage. The power converter exits the light load mode back to the first mode of operation in response to the compensator voltage being beyond the threshold voltage.Type: GrantFiled: August 3, 2020Date of Patent: May 30, 2023Assignee: Silanna Asia Pte LtdInventors: Rawinder Dharmalinggam, Kais Badami, Kok Soon Yeo
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Publication number: 20230006554Abstract: An improved power converter produces power through a power switch in response to an activation signal that has an on-time and a switching frequency. An on-time signal has a constant on-time and controls the on-time of the activation signal. An error signal indicates that the switching frequency is not equal to a reference frequency. A step up signal and a step down signal are based on the error signal. A count signal is increased in response to the step up signal and decreased in response to the step down signal. An on-time pulse has a duration that is related to a value of the count signal. The on-time pulse controls the constant on-time of the on-time signal and maintains the switching frequency at about the reference frequency.Type: ApplicationFiled: September 13, 2022Publication date: January 5, 2023Applicant: Silanna Asia Pte LtdInventors: Rawinder Dharmalinggam, Tiong Lim
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Patent number: 11469667Abstract: An improved power converter produces power through a power switch in response to an activation signal that has an on-time and a switching frequency. An on-time signal has a constant on-time and controls the on-time of the activation signal. An error signal indicates that the switching frequency is not equal to a reference frequency. A step up signal and a step down signal are based on the error signal. A count signal is increased in response to the step up signal and decreased in response to the step down signal. An on-time pulse has a duration that is related to a value of the count signal. The on-time pulse controls the constant on-time of the on-time signal and maintains the switching frequency at about the reference frequency.Type: GrantFiled: October 14, 2020Date of Patent: October 11, 2022Assignee: Silanna Asia Pte LtdInventors: Rawinder Dharmalinggam, Tiong Lim
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Publication number: 20210028701Abstract: An improved power converter produces power through a power switch in response to an activation signal that has an on-time and a switching frequency. An on-time signal has a constant on-time and controls the on-time of the activation signal. An error signal indicates that the switching frequency is not equal to a reference frequency. A step up signal and a step down signal are based on the error signal. A count signal is increased in response to the step up signal and decreased in response to the step down signal. An on-time pulse has a duration that is related to a value of the count signal. The on-time pulse controls the constant on-time of the on-time signal and maintains the switching frequency at about the reference frequency.Type: ApplicationFiled: October 14, 2020Publication date: January 28, 2021Applicant: Silanna Asia Pte LtdInventors: Rawinder Dharmalinggam, Tiong Lim
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Publication number: 20210006165Abstract: During a first mode of operation, a zero current detect (ZCD) signal is asserted in response to detecting a zero current condition at a switch node of a power converter. The power converter enters a light load mode of operation when the ZCD signal is asserted between a beginning point and a trigger point of a period of a PWM signal. A compensator voltage is generated based on a feedback voltage indicative of an output voltage. The compensator voltage is compared to a threshold voltage that represents a limit for the compensator voltage during the light load mode of operation determined over a range of the output voltage. The power converter exits the light load mode back to the first mode of operation in response to the compensator voltage being beyond the threshold voltage.Type: ApplicationFiled: August 3, 2020Publication date: January 7, 2021Applicant: Silanna Asia Pte LtdInventors: Rawinder Dharmalinggam, Kais Badami, Kok Soon Yeo
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Patent number: 10811969Abstract: An improved power converter produces power through a power switch in response to an activation signal that has an on-time and a switching frequency. An on-time signal has a constant on-time and controls the on-time of the activation signal. An error signal indicates that the switching frequency is not equal to a reference frequency. A step up signal and a step down signal are based on the error signal. A count signal is increased in response to the step up signal and decreased in response to the step down signal. An on-time pulse has a duration that is related to a value of the count signal. The on-time pulse controls the constant on-time of the on-time signal and maintains the switching frequency at about the reference frequency.Type: GrantFiled: September 10, 2019Date of Patent: October 20, 2020Assignee: Silanna Asia Pte LtdInventors: Rawinder Dharmalinggam, Tiong Lim
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Patent number: 10763738Abstract: During a first mode of operation, a zero current detect (ZCD) signal is asserted in response to detecting a zero current condition at a switch node of a power converter. The power converter enters a light load mode of operation when the ZCD signal is asserted between a beginning point and a trigger point of a period of a PWM signal. A compensator voltage is generated based on a feedback voltage indicative of an output voltage. The compensator voltage is compared to a threshold voltage that represents a limit for the compensator voltage during the light load mode of operation determined over a range of the output voltage. The power converter exits the light load mode back to the first mode of operation in response to the compensator voltage being beyond the threshold voltage.Type: GrantFiled: July 3, 2019Date of Patent: September 1, 2020Assignee: Silanna Asia Pte LtdInventors: Rawinder Dharmalinggam, Kais Badami, Kok Soon Yeo
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Publication number: 20200220460Abstract: An improved power converter produces power through a power switch in response to an activation signal that has an on-time and a switching frequency. An on-time signal has a constant on-time and controls the on-time of the activation signal. An error signal indicates that the switching frequency is not equal to a reference frequency. A step up signal and a step down signal are based on the error signal. A count signal is increased in response to the step up signal and decreased in response to the step down signal. An on-time pulse has a duration that is related to a value of the count signal. The on-time pulse controls the constant on-time of the on-time signal and maintains the switching frequency at about the reference frequency.Type: ApplicationFiled: September 10, 2019Publication date: July 9, 2020Applicant: Silanna Asia Pte LtdInventors: Rawinder Dharmalinggam, Tiong Lim
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Patent number: 10418902Abstract: An improved power converter produces power through a power switch in response to an activation signal that has an on-time and a switching frequency. An on-time signal has a constant on-time and controls the on-time of the activation signal. An error signal indicates that the switching frequency is not equal to a reference frequency. A step up signal and a step down signal are based on the error signal. A count signal is increased in response to the step up signal and decreased in response to the step down signal. An on-time pulse has a duration that is related to a value of the count signal. The on-time pulse controls the constant on-time of the on-time signal and maintains the switching frequency at about the reference frequency.Type: GrantFiled: January 4, 2019Date of Patent: September 17, 2019Assignee: Silanna Asia Pte LtdInventors: Rawinder Dharmalinggam, Tiong Lim
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Patent number: 7834709Abstract: A voltage controlled oscillator and a load cell circuit usable in VCO are provided. The VCO features an internal compensation for process, voltage and temperature using a replica of half of the oscillating stage. The load cell circuit comprises a bias transistor to drain a predetermined current from the oscillating stage, a control transistor to vary resistance offered by it responsive to a control voltage applied and a resistor adapted to provide a clamp resistance.Type: GrantFiled: October 3, 2008Date of Patent: November 16, 2010Assignee: PLX Technology, Inc.Inventors: Kanan Saurabh, Rawinder Dharmalinggam
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Publication number: 20100085127Abstract: A voltage controlled oscillator and a load cell circuit usable in VCO are provided. The VCO features an internal compensation for process, voltage and temperature using a replica of half of the oscillating stage. The load cell circuit comprises a bias transistor to drain a predetermined current from the oscillating stage, a control transistor to vary resistance offered by it responsive to a control voltage applied and a resistor adapted to provide a clamp resistance.Type: ApplicationFiled: October 3, 2008Publication date: April 8, 2010Inventors: Kanan Saurabh, Rawinder Dharmalinggam
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Patent number: 7489195Abstract: A variable gain amplifying circuit comprises two stages, a first stage and a second stage with a common voltage-to-current converter. Each stage comprises two BJTs, two voltage controlled current sources, a variable resistor with a variable resistance, and the common voltage-to-current converter. The two BJTs construct a differential amplifier for amplifying a pair of differential signals. The variable resistor with the variable resistance is connected between the emitters of the two BJTs wherein the variable resistance of the variable resistor is represented as RE. The variable resistance RE is controlled by a control voltage Vctrl. The two voltage controlled current sources are respectively connected between the corresponding emitter of BJTs and ground. The currents respectively through the voltage controlled current sources are equal to each other and represented as IE. The current IE is controlled by the common voltage-to-current converter according the control voltage Vctrl.Type: GrantFiled: February 8, 2007Date of Patent: February 10, 2009Assignee: MediaTek Singapore Pte LtdInventors: Wee Liang Lien, Rawinder Dharmalinggam, Ten Voon Wong
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Patent number: 7477098Abstract: A tuning circuit for tuning an active filter includes a resistor-capacitor circuit comprising a variable capacitor and a resistor equivalent to a first resistor and a second resistor serially connected to the first resistor, a voltage generator for providing a constant reference voltage to the first resistor, a current replicating unit for replicating a current based on the constant reference voltage, a comparator for comparing a charging voltage as the current is charging a variable capacitor with the constant reference voltage, a counter for counting a number of cycles of a clock signal until the charging voltage reaches the constant reference voltage, a adjustment unit for calibrating a capacitance of the variable capacitor based on the number of cycles of a clock signal and a target count value associated with a predetermined RC time constant.Type: GrantFiled: February 8, 2007Date of Patent: January 13, 2009Assignee: MediaTek Singapore Pte LtdInventors: Rawinder Dharmalinggam, Chinq-shiun Chiu
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Publication number: 20080191795Abstract: A tuning circuit for tuning an active filter includes a resistor-capacitor circuit comprising a variable capacitor and a resistor equivalent to a first resistor and a second resistor serially connected to the first resistor, a voltage generator for providing a constant reference voltage to the first resistor, a current replicating unit for replicating a current based on the constant reference voltage, a comparator for comparing a charging voltage as the current is charging a variable capacitor with the constant reference voltage, a counter for counting a number of cycles of a clock signal until the charging voltage reaches the constant reference voltage, a adjustment unit for calibrating a capacitance of the variable capacitor based on the number of cycles of a clock signal and a target count value associated with a predetermined RC time constant.Type: ApplicationFiled: February 8, 2007Publication date: August 14, 2008Inventors: Rawinder Dharmalinggam, Chinq-shiun Chiu
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Publication number: 20080191803Abstract: A variable gain amplifying circuit comprises two stages, a first stage and a second stage with a common voltage-to-current converter. Each stage comprises two BJTs, two voltage controlled current sources, a variable resistor with a variable resistance, and the common voltage-to-current converter. The two BJTs construct a differential amplifier for amplifying a pair of differential signals. The variable resistor with the variable resistance is connected between the emitters of the two BJTs wherein the variable resistance of the variable resistor is represented as RE. The variable resistance RE is controlled by a control voltage Vctrl. The two voltage controlled current sources are respectively connected between the corresponding emitter of BJTs and ground. The currents respectively through the voltage controlled current sources are equal to each other and represented as IE. The current IE is controlled by the common voltage-to-current converter according the control voltage Vctrl.Type: ApplicationFiled: February 8, 2007Publication date: August 14, 2008Applicant: MediaTek Singapore Pte LtdInventors: Wee Liang Lien, Rawinder Dharmalinggam, Ten Voon Wong
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Publication number: 20080191794Abstract: A method of tuning an RC time constant includes the steps of providing a predetermined time period value associated with a predetermined RC time constant, providing a DC reference signal, generating an second signal responsive to charging a capacitor until magnitudes of the second signal and the DC reference signal are matched, determining a charging time period of the capacitor, and adjusting a capacitance of the capacitor to comply with the predetermined RC time constant based on the time period and the predetermined time period value.Type: ApplicationFiled: February 8, 2007Publication date: August 14, 2008Applicant: MediaTek Inc.Inventors: Chinq-shiun Chiu, Tze-yee Sin, Rawinder Dharmalinggam