Patents by Inventor Pallab Midya
Pallab Midya 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: 8988049Abstract: A DC power stage provides a power output that tracks a PCM signal input. A mapping unit generates an integer number of N digital PWM signals each switched at a same switching frequency by switching states of the PWM signals one at a time based on a level of the PCM signal input. An imbalance correction unit adjusts a duty ratio of the PWM signals relative to one another based on differentially accumulating errors among the PWM signals to prevent divergence of PWM signals. N corresponding switches therefrom switch power from a DC power source. N inductances in parallel produce a combined signal that is low pass filtered to provide the power output. Switching is between only those state combinations where the switching frequency is cancelled in the combined signal. The switching frequency is a sampling frequency of the PCM signal input divided by a product of 2 times N.Type: GrantFiled: June 19, 2013Date of Patent: March 24, 2015Assignee: Futurewei Technologies, Inc.Inventor: Pallab Midya
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Publication number: 20140375382Abstract: A DC power stage provides a power output that tracks a PCM signal input. A mapping unit generates an integer number of N digital PWM signals each switched at a same switching frequency by switching states of the PWM signals one at a time based on a level of the PCM signal input. An imbalance correction unit adjusts a duty ratio of the PWM signals relative to one another based on differentially accumulating errors among the PWM signals to prevent divergence of PWM signals. N corresponding switches therefrom switch power from a DC power source. N inductances in parallel produce a combined signal that is low pass filtered to provide the power output. Switching is between only those state combinations where the switching frequency is cancelled in the combined signal. The switching frequency is a sampling frequency of the PCM signal input divided by a product of 2 times N.Type: ApplicationFiled: June 19, 2013Publication date: December 25, 2014Applicant: ADX RESEARCH, INC.Inventor: Pallab Midya
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Patent number: 8638836Abstract: A transceiver mitigates signal leakage into a receive path from a transmit path. A subtraction circuit determines a difference between a receive signal and a compensation signal to produce a compensated receive signal prior to demodulation by a demodulator. An equalizer both amplitude adjusts and phase adjusts orthogonal baseband transmit signals based on the difference from the subtraction circuit to produce the compensation signal. A digital tuning circuit determines at least one amplitude adjust coefficient to be used by the equalizer. The equalizer can have a polarity switch or a variable attenuator or a variable delay.Type: GrantFiled: August 31, 2009Date of Patent: January 28, 2014Assignee: Freescale Semiconductor, Inc.Inventors: Pallab Midya, Rakers L Patrick, William J Roeckner
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Publication number: 20130241660Abstract: Generally, this disclosure provides an apparatus, method and system for DC-DC conversion. The apparatus may include a switch network including a first plurality of switches configured to operate in a Buck mode to generate an output voltage that is less than an input voltage, and a second plurality of switches configured to operate in an Up mode to generate an output voltage that is greater than the input voltage. The apparatus of this example may further include controller circuitry configured to generate control signals to control the conduction state of the first plurality of switches and the second plurality of switches based on a variable reference signal indicative of power demands from a load coupled to the switch network.Type: ApplicationFiled: September 6, 2012Publication date: September 19, 2013Applicant: FAIRCHILD SEMICONDUCTOR CORPORATIONInventor: Pallab Midya
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Publication number: 20120275544Abstract: A system according to one embodiment includes a digital data modulator configured to generate encoded symbols; an envelope detector configured to receive the encoded symbols and to estimate transmission power information associated with the encoded symbols; a peak detector configured to receive the transmission power information, detect a peak transmission power from two or more sequential data points of the received transmission power information, and to generate a power regulation signal representative of the detected peak transmission power; and a digital to analog converter (DAC) configured to receive the power regulation signal and to provide a reference voltage to a power supply associated with an RF amplifier.Type: ApplicationFiled: December 2, 2011Publication date: November 1, 2012Inventors: Pallab Midya, Joseph M. Ingino, JR.
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Patent number: 8278902Abstract: A switching power converter converts an input DC voltage to an output DC voltage using a switch to selectively connect an input DC voltage energy source. A switching controller controls the switch. A pulse width modulation centering signal is generated by a spread spectrum clock signal generator. An error amplifier of the switching controller generates an analog error signal based on a switching voltage measured after the switching of the switching power converter, the output voltage of the switching power converter, the pulse width modulation centering signal and a reference. A pulse width modulated signal generator generates the pulse width modulation signal to control the switch of the switching power converter based on the pulse width modulation centering signal and the analog error signal.Type: GrantFiled: July 15, 2009Date of Patent: October 2, 2012Assignee: Freescale Semiconductor, Inc.Inventors: Pallab Midya, Siamak Abedinpour, William J Roeckner
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Patent number: 8228117Abstract: A switching audio amplifier circuit drives a switching audio amplifier stage using a digital PWM signal from an audio source. A PWM duty ratio modifier modifies an edge timing of the digital PWM signal to produce a modified digital PWM signal. A mode switch switches between the digital PWM signal and the modified digital PWM signal in a way that masks audible noise such as clicks and pops at power-up and power-down of the switching audio amplifier. An integrating error amplifier compares a difference between the digital PWM signal and an amplified PWM signal and integrates the difference to control the edge timing modified by the PWM duty ratio modifier. A mode controller can apply an offset signal to the integrating error amplifier and can control the switching of the mode switch.Type: GrantFiled: July 15, 2009Date of Patent: July 24, 2012Assignee: Freescale Semiconductor, Inc.Inventors: Pallab Midya, William J Roeckner
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Publication number: 20110051833Abstract: A transceiver mitigates signal leakage into a receive path from a transmit path. A subtraction circuit determines a difference between a receive signal and a compensation signal to produce a compensated receive signal prior to demodulation by a demodulator. An equalizer both amplitude adjusts and phase adjusts orthogonal baseband transmit signals based on the difference from the subtraction circuit to produce the compensation signal. A digital tuning circuit determines at least one amplitude adjust coefficient to be used by the equalizer. The equalizer can have a polarity switch or a variable attenuator or a variable delay.Type: ApplicationFiled: August 31, 2009Publication date: March 3, 2011Applicant: FREESCALE SEMICONDUCTOR, INC.Inventors: Pallab Midya, Patrick L. Rakers, William J. Roeckner
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Publication number: 20110012575Abstract: A switching power converter converts an input DC voltage to an output DC voltage using a switch to selectively connect an input DC voltage energy source. A switching controller controls the switch. A pulse width modulation centering signal is generated by a spread spectrum clock signal generator. An error amplifier of the switching controller generates an analog error signal based on a switching voltage measured after the switching of the switching power converter, the output voltage of the switching power converter, the pulse width modulation centering signal and a reference. A pulse width modulated signal generator generates the pulse width modulation signal to control the switch of the switching power converter based on the pulse width modulation centering signal and the analog error signal.Type: ApplicationFiled: July 15, 2009Publication date: January 20, 2011Applicant: FREESCALE SEMICONDUCTOR, INC.Inventors: Pallab Midya, Siamak Abedinpour, William J. Roeckner
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Publication number: 20110012674Abstract: A switching audio amplifier circuit drives a switching audio amplifier stage using a digital PWM signal from an audio source. A PWM duty ratio modifier modifies an edge timing of the digital PWM signal to produce a modified digital PWM signal. A mode switch switches between the digital PWM signal and the modified digital PWM signal in a way that masks audible noise such as clicks and pops at power-up and power-down of the switching audio amplifier. An integrating error amplifier compares a difference between the digital PWM signal and an amplified PWM signal and integrates the difference to control the edge timing modified by the PWM duty ratio modifier. A mode controller can apply an offset signal to the integrating error amplifier and can control the switching of the mode switch.Type: ApplicationFiled: July 15, 2009Publication date: January 20, 2011Applicant: FREESCALE SEMICONDUCTOR, INC.Inventors: Pallab Midya, William J. Roeckner
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Patent number: 7825726Abstract: A switching amplifier drives a load or audio transducer. A digital integral noise shaping circuit converts a digital input such as audio content to an output digital pulse width modulated signal using an integrator. The integrator integrates the digital input, a variable frequency reference pulse width modulated signal and an inverse of the output digital pulse width modulated signal. A half bridge amplifier receives the output digital pulse width modulated signal and drives the load or audio transducer. A variable frequency generator generates the variable frequency reference pulse width modulated signal with an approximately equal duty ratio or alternatively varies the variable frequency pulse width modulated signal above and below about a fifty percent duty ratio.Type: GrantFiled: October 30, 2008Date of Patent: November 2, 2010Assignee: Freescale Semiconductor, Inc.Inventors: Pallab Midya, Matthew R Miller, William J Roeckner
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Patent number: 7777563Abstract: A circuit includes a variable frequency generator circuit and a quantization circuit. The variable frequency generator circuit provides a discontinuous switching frequency signal. The variable frequency generator circuit varies the discontinuous switching frequency signal between a first and second frequency while avoiding at least one frequency band between the first and second frequency. The quantization circuit provides a plurality discrete switching signals each separated by a second frequency band that vary in accordance with the discontinuous switching frequency signal, wherein the avoided frequency band of the discontinuous switching frequency signal is greater than the second frequency band.Type: GrantFiled: December 18, 2008Date of Patent: August 17, 2010Assignee: Freescale Semiconductor, Inc.Inventors: Pallab Midya, William J. Roeckner
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Publication number: 20100156527Abstract: A circuit includes a variable frequency generator circuit and a quantization circuit. The variable frequency generator circuit provides a discontinuous switching frequency signal. The variable frequency generator circuit varies the discontinuous switching frequency signal between a first and second frequency while avoiding at least one frequency band between the first and second frequency. The quantization circuit provides a plurality discrete switching signals each separated by a second frequency band that vary in accordance with the discontinuous switching frequency signal, wherein the avoided frequency band of the discontinuous switching frequency signal is greater than the second frequency band.Type: ApplicationFiled: December 18, 2008Publication date: June 24, 2010Inventors: Pallab Midya, William J. Roeckner
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Publication number: 20100109767Abstract: A switching amplifier drives a load or audio transducer. A digital integral noise shaping circuit converts a digital input such as audio content to an output digital pulse width modulated signal using an integrator. The integrator integrates the digital input, a variable frequency reference pulse width modulated signal and an inverse of the output digital pulse width modulated signal. A half bridge amplifier receives the output digital pulse width modulated signal and drives the load or audio transducer. A variable frequency generator generates the variable frequency reference pulse width modulated signal with an approximately equal duty ratio or alternatively varies the variable frequency pulse width modulated signal above and below about a fifty percent duty ratio.Type: ApplicationFiled: October 30, 2008Publication date: May 6, 2010Applicant: FREESCALE SEMICONDUCTOR, INC.Inventors: Pallab Midya, Matthew R. Miller, William J. Roeckner
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Patent number: 7667552Abstract: A system is described for generating a discrete noise-shaped variable switching frequency signal that may be used to define a digital pulse width modulation (“PWM”) period. The system may define a switching frequency waveform that may be used to generate a current switching frequency signal as a function of a system clock. The system may quantize the current switching frequency signal to generate a discrete switching frequency signal that is realizable with the system clock. The system may detect quantization noise and input the noise into the current switching frequency signal to eliminate or reduce discrete tones at the switching frequencies of a PWM signal spectrum.Type: GrantFiled: April 10, 2007Date of Patent: February 23, 2010Assignee: Freescale Semiconductor, Inc.Inventors: Pallab Midya, Xin Geng
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Patent number: 7649961Abstract: A digital amplifier and method are provided to convert digital base-band signals to a pair of digital switching waveforms switching at a carrier frequency to create a modulated RF signal. The digital amplifier contains variable frequency suppressed carrier PWM generators that produce in-phase and quadrature-phase differential signals, a mixer that combines the differential signals, a decoder that decodes the combined signals, and a power stage that receives signals from the decoder and provides an amplified signal at the carrier frequency using switches. The mixer combines the differential signals such that only one of the differential signals is output in a period. The carrier generators have integral noise shaping and use a random period signal to re-distribute quantization noise to a band outside an RF band of interest and reduce EMI of the RF signal.Type: GrantFiled: June 20, 2005Date of Patent: January 19, 2010Assignee: Freescale Semiconductor, Inc.Inventor: Pallab Midya
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Patent number: 7629840Abstract: A switching amplifier includes a power stage, a low pass filter, a combining circuit, and a feedback correction circuit. The power stage has an input terminal and an output terminal. The low pass filter has an input terminal coupled to the output terminal of the power stage, and an output terminal for providing a filtered pulse width modulated signal. The combining circuit has a first input terminal coupled to the output terminal of the power stage, a second input terminal coupled to the output terminal of the low pass filter, and an output terminal. The feedback correction circuit has a first input terminal for receiving a reference pulse width modulated signal, a second input terminal coupled to the output terminal of the combining circuit, and an output terminal coupled to the input terminal of the power stage.Type: GrantFiled: October 22, 2007Date of Patent: December 8, 2009Assignee: Freescale Semiconductor, Inc.Inventors: Pallab Midya, Theresa Paulo, William J. Roeckner
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Publication number: 20090261902Abstract: A circuit (104, 106) includes a comparison circuit (202, 504, 506, 602) and a correction circuit (204, 508, 510, 604). The comparison circuit provides a comparison signal (212, 524, 526, 612) in response to an error value (210, 520, 522, 610) and a reference value (214). The error value is based on a pulse modulated input signal (114) and a pulse modulated output signal (118). The correction circuit asynchronously provides a corrected pulse modulated signal (116) by selectively delaying and advancing an edge of the pulse modulated input signal based on the comparison signal. The pulse modulated output signal is based on the corrected pulse modulated signal.Type: ApplicationFiled: April 17, 2008Publication date: October 22, 2009Applicant: Freescale Semiconductor, Inc.Inventors: Pallab Midya, Matthew R. Miller, Theresa Paulo, William J. Roeckner
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Publication number: 20090102549Abstract: A switching amplifier includes a power stage, a low pass filter, a combining circuit, and a feedback correction circuit. The power stage has an input terminal and an output terminal. The low pass filter has an input terminal coupled to the output terminal of the power stage, and an output terminal for providing a filtered pulse width modulated signal. The combining circuit has a first input terminal coupled to the output terminal of the power stage, a second input terminal coupled to the output terminal of the low pass filter, and an output terminal. The feedback correction circuit has a first input terminal for receiving a reference pulse width modulated signal, a second input terminal coupled to the output terminal of the combining circuit, and an output terminal coupled to the input terminal of the power stage.Type: ApplicationFiled: October 22, 2007Publication date: April 23, 2009Inventors: Pallab Midya, Theresa Paulo, William J. Roeckner
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Publication number: 20080252392Abstract: A system is described for generating a discrete noise-shaped variable switching frequency signal that may be used to define a digital pulse width modulation (“PWM”) period. The system may define a switching frequency waveform that may be used to generate a current switching frequency signal as a function of a system clock. The system may quantize the current switching frequency signal to generate a discrete switching frequency signal that is realizable with the system clock. The system may detect quantization noise and input the noise into the current switching frequency signal to eliminate or reduce discrete tones at the switching frequencies of a PWM signal spectrum.Type: ApplicationFiled: April 10, 2007Publication date: October 16, 2008Inventors: Pallab Midya, Xin Geng