-
1.发明授权公开(公告)号：US12160248B2
公开(公告)日：2024-12-03
申请号：US18098544
申请日：2023-01-18
Inventor： Vamsikrishna Parupalli , Mikel Ash , Jianping Wen , Melvin L. Hagge
Abstract: A SAR ADC may include a plurality of capacitor networks, wherein each capacitor network of a plurality of capacitor networks has a plurality of sampling capacitors for sampling over a plurality of sampling sub-phases an analog input signal to the SAR ADC and at least one non-sampling capacitor. The SAR ADC may also include a DAC comprising a plurality of sub-DACs including at least a first sub-DAC representing most significant bits of an output of the SAR ADC, wherein the output of the first sub-DAC is coupled to the sampling capacitors of the plurality of capacitor networks and a second sub-DAC representing bits of the output of the SAR ADC lesser in magnitude significance than those of the first sub-DAC, wherein the output of the second sub-DAC is coupled to a respective one of at least one non-sampling capacitor of each of the plurality of capacitor networks.
-
公开(公告)号：US11962261B2
公开(公告)日：2024-04-16
申请号：US17230789
申请日：2021-04-14
Inventor： Vamsikrishna Parupalli , Mark May , Eric B. Smith , Zhong You
CPC classification number: H02P7/29 , G02B7/09 , G02B27/646 , H02P7/04 , H02P7/292
Abstract: An electronic motor control system provides selectable linear and pulse-width modulated (PWM) operation without generating cross-over distortion. The system includes an output stage that has a pair of push-pull drivers each coupled to a terminal of the motor. The electronic motor control system also includes a pulse-width modulated (PWM) driver for providing pulse-width modulated drive signals to an input of the output stage when the pulse-width modulated mode is selected and a linear amplifier stage that provides a linear analog signal to the input of the output stage in linear mode, so that both drivers are operated to supply the current to the motor. In pulse-width modulated mode, a driver is selected for PWM operation, while the other driver is operated to supply a fixed voltage. A feedback control loop senses motor current and provides outputs to the pulse-width modulator and the linear amplifier stage.
-
公开(公告)号：US20230128810A1
公开(公告)日：2023-04-27
申请号：US17510707
申请日：2021-10-26
Inventor： Vamsikrishna Parupalli , Nishant Jain , Mengde Wang
Abstract: An electronic control system provides selectable linear and pulse-width modulated (PWM) operation with reduced disruption when changing from PWM operation to linear operation. The system includes an output stage that has a push-pull driver coupled to the load, which may be a motor, a haptic device, or other device requiring current-mode control. The system also includes a pulse-width modulated (PWM) driver for providing pulse-width modulated drive signals to gates of the transistors of the output stage when a pulse-width modulated mode is selected, and a linear amplifier stage that provides a linear analog signal to the gates of the transistors when a linear mode is selected. A pre-charging circuit pre-charges the gates during a pre-charge cycle that is initiated when the operating mode changes from the PWM operating more to the linear operating mode.
-
公开(公告)号：US10901012B2
公开(公告)日：2021-01-26
申请号：US16354781
申请日：2019-03-15
Inventor： Katy Holland , Vamsikrishna Parupalli , Christian Larsen , Graeme Mackay
Abstract: A method for calculating a calibration gain used for common-mode rejection in a current sensing system may include measuring a first value of a common-mode voltage associated with the current sensing system and a first output value of the current sensing system occurring at the first value of the common-mode voltage, measuring a second value of the common-mode voltage associated with the current sensing system and a second output value of the current sensing system occurring at the second value of the common-mode voltage, and based on a difference between the second output value of the current sensing system and the first output value of the current sensing system and a difference between the second value of the common-mode voltage and the first value of the common-mode voltage, calculating the calibration gain.
-
公开(公告)号：US10164576B2
公开(公告)日：2018-12-25
申请号：US15582233
申请日：2017-04-28
Inventor： Graeme Gordon MacKay , Lei Zhu , Ku He , Vamsikrishna Parupalli
Abstract: In accordance with embodiments of the present disclosure, a method for power supply rejection for an amplifier may include generating a correction signal by multiplying a quantity indicative of a power supply voltage of the amplifier by a transfer function defining a response from the power supply voltage of the amplifier to an output signal of the amplifier and subtracting the correction signal from a signal within a signal path of a circuit comprising the amplifier.
-
Patent Agency Ranking
公开(公告)号：US20210249998A1
公开(公告)日：2021-08-12
申请号：US16786956
申请日：2020-02-10
Inventor： Vamsikrishna Parupalli , John L. Melanson
IPC: H03F1/34
Abstract: A dynamically stabilizable amplifier drives an output current into an RLC load. A driver stage generates the output current, and a control circuit compares a current level of the amplifier output with a threshold and selectively enables a stabilizing resistor (to selectively shunt the load or dampen in series with the load, depending on RLC load type) at the driver stage output based on the comparison so that the amplifier is stable across a range of the output current level. The control circuit disables the resistor when the output current is above the highest threshold and enables it when below. The control circuit may control the resistor to have one of multiple resistance values based on a comparison with multiple thresholds. The output current level may be determined by replicating the output current level or by an input current level that sets the output current level independent of the load.
-
公开(公告)号：US10649015B1
公开(公告)日：2020-05-12
申请号：US15943154
申请日：2018-04-02
Inventor： Vikrant Arumugam , Amar Vellanki , Vamsikrishna Parupalli , Zhong You , Johann G. Gaboriau , John L. Melanson
IPC: G01R27/26
Abstract: A method may include applying an excitation signal to a capacitor of the capacitive sensor which causes generation of a modulated signal from an input signal indicative of a variance in a capacitance of the capacitor, detecting the modulated signal with a detector to generate a detected modulated signal that has a phase shift relative to the excitation signal, demodulating the detected modulated signal into an in-phase component and a quadrature component using a reference signal, nullifying the quadrature component by setting a phase of the reference signal relative to the excitation signal to compensate for the phase shift, and outputting the in-phase component as an unmodulated output signal representative of the capacitance.
-
公开(公告)号：US10123143B2
公开(公告)日：2018-11-06
申请号：US15276437
申请日：2016-09-26
Inventor： Vamsikrishna Parupalli , Lingli Zhang , Jeremy Babcock , Marc L. Tarabbia
Abstract: Errors in measurements of a resistor to monitor current through a speaker may be corrected to improve the accuracy, performance, or quality of other signals affected by the measurement. Error may occur in the current measurement resulting from variations in measurements involving the resistor, such as errors based on the sense resistor's response to temperature or voltage differential. Correcting the measurement errors can prevent the overcurrent condition from occurring, and otherwise improve audio output from the speaker. Thus, a method for correcting measurements in a speaker monitoring circuit may include monitoring a current through a speaker by receiving a measurement that is correlated to the current output through the speaker; and correcting the measurement for one or more inaccuracies in the measurement.
-
公开(公告)号：US20180091911A1
公开(公告)日：2018-03-29
申请号：US15276437
申请日：2016-09-26
Inventor： Vamsikrishna Parupalli , Lingli Zhang , Jeremy Babcock , Marc L. Tarabbia
CPC classification number: H04R29/001 , H04R3/007
Abstract: Errors in measurements of a resistor to monitor current through a speaker may be corrected to improve the accuracy, performance, or quality of other signals affected by the measurement. Error may occur in the current measurement resulting from variations in measurements involving the resistor, such as errors based on the sense resistor's response to temperature or voltage differential. Correcting the measurement errors can prevent the overcurrent condition from occurring, and otherwise improve audio output from the speaker. Thus, a method for correcting measurements in a speaker monitoring circuit may include monitoring a current through a speaker by receiving a measurement that is correlated to the current output through the speaker; and correcting the measurement for one or more inaccuracies in the measurement.
-
公开(公告)号：US20170141732A1
公开(公告)日：2017-05-18
申请号：US15069733
申请日：2016-03-14
Inventor： Vamsikrishna Parupalli , Itisha Tyagi
CPC classification number: G01R19/10 , G01R15/14 , H03F1/0205 , H03F3/45 , H03F3/45475 , H03F3/45937 , H03F2200/171 , H03F2200/462 , H03F2203/45048 , H03F2203/45081 , H03F2203/45101 , H04R3/007
Abstract: The overall performance of a current sense amplifier system may be improved by increasing the common mode rejection of the system. In particular, improved current sense amplifiers may be configured to use a first signal path coupled to the amplifier and a first input terminal, wherein the first signal path is configured to measure the current through a device by generating a voltage proportional to the measured current, wherein the generated voltage comprises a small signal voltage with a large common mode voltage, and a second signal path coupled to the amplifier and the first input terminal, wherein the second signal path is configured to reduce the common mode of the generated voltage by level shifting the generated voltage to reduce the common mode voltage.
-
-
-
-
-
-
-
-
-
Search Results
31
records
(took 0.016 seconds)
