Patents by Inventor Aleksandar Prodic

Aleksandar Prodic 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).

  • Publication number: 20080303501
    Abstract: A digital controller for low-power DC-DC switch mode power supplies (SMPS) suitable for on-chip implementation and use in portable battery-powered systems is provided. The digital controller allows operation at ultra high constant switching frequencies and can be implemented with a simple low-power digital hardware. The digital controller includes a digital pulse width modulator (DPWM), based on a multibit 2nd orders sigma-delta (?-?) principle, and a dual-sampling mode PID compensator. The output voltage is either sampled at a frequency lower than the switching frequency (undersampled) or sampled at the switching rate. In steady-state, undersampling results in reduced power consumption, while during transients, sampling at the switching rate provides fast transient response. Another aspect of the present invention is a dual sampling/clocking scheme, which is relied on by the DPWM described.
    Type: Application
    Filed: October 3, 2005
    Publication date: December 11, 2008
    Inventor: Aleksandar Prodic
  • Patent number: 7459951
    Abstract: A hybrid digital pulse width modulator can have a delay line with digitally programmable delay cells. The digitally programmable delay cells can be adjusted by a digital correction signal from a delay matching circuit.
    Type: Grant
    Filed: February 22, 2006
    Date of Patent: December 2, 2008
    Assignee: Exar Corporation
    Inventor: Aleksandar Prodic
  • Publication number: 20080252280
    Abstract: The present invention is a voltage mode digital controller for low-power high-frequency dc-dc converters that has recovery time approaching physical limitations of a given power stage. It consists of a digital controller with load transient response approaching physical limitations of a given power stage that is suitable for low-power SMPS. In one aspect the invention is a method of utilizing a continuous-time digital signal processor (CT-DSP) for regulation of the operation of switch-mode power supplies. A CT-DSP can be used to instantaneously detect changes of voltage or current during transition periods and immediately perform control action that results in the fastest possible response. The invention may include current program mode controllers for SMPS where the input current is sensed as well as power factor correction rectifiers (PFC), where often input voltage, input current and output voltage are sensed.
    Type: Application
    Filed: April 10, 2008
    Publication date: October 16, 2008
    Inventors: Aleksandar Prodic, Zhenyu Zhao
  • Publication number: 20080224756
    Abstract: A low-power digital pulse-width modulator (DPWM) architecture for high frequency dc-dc switch-mode power supplies (SMPS) is disclosed that is well-suited for integration in power management systems of small handheld devices. The DPWM can operate in a stand-alone mode, without external clock, and can be implemented on a portion of silicon area needed for other DPWM solutions. In addition it has low power consumption and provides a good linearity of the input-to-output characteristic, also not characteristic for other architectures.
    Type: Application
    Filed: February 20, 2008
    Publication date: September 18, 2008
    Applicant: EXAR CORPORATION
    Inventors: Aleksandar Prodic, Kun Wang, Amir Parayandeh
  • Publication number: 20080225938
    Abstract: A digital controller for dc-dc switching converters can operate under light load conditions. The controller can be suitable for the use in switch-mode power supplies providing regulated output voltage for handheld devices and other low-power electronics. To create long time intervals, compared to the propagation time of digital logic a DPFM/DPAM can use a ring oscillator with two sets of delay cells and two signals racing around the ring.
    Type: Application
    Filed: February 20, 2008
    Publication date: September 18, 2008
    Applicant: EXAR CORPORATION
    Inventors: Aleksandar Prodic, Kun Wang, Amir Parayandeh
  • Publication number: 20080204160
    Abstract: A multiphase hybrid digital pulse width modulator can comprise a counter that is selectable between at least two different numbers of states to indicate a first portion of a switching period. Unclocked logic can indicate a second portion of the switching period. The unclocked logic can include a delay line.
    Type: Application
    Filed: July 3, 2007
    Publication date: August 28, 2008
    Applicant: SIPEX CORPORATION
    Inventors: Aleksandar Prodic, Zdravko Lukic
  • Publication number: 20080204296
    Abstract: In embodiments, a new analog-to-digital converter (ADC) architecture can be used with switch-mode power supplies (SMPS) operating at switching frequencies higher than 10 MHz. Analog-to-digital converter embodiments can achieve very low power consumption, fast conversion time, and can be implemented with a simple hardware. Another noteworthy benefit is that certain ADC embodiments feature a non-linear gain characteristic that provides improved load transient response for digital controllers.
    Type: Application
    Filed: February 20, 2008
    Publication date: August 28, 2008
    Applicant: Exar Corporation
    Inventors: Aleksandar Prodic, Zdravko Lukic
  • Publication number: 20080204290
    Abstract: A voltage-to-time based windowed analog-to-digital converter (ADC) can have programmable reference voltage, conversion time, and accuracy of voltage regulation. The ADC can be fully implemented on a small silicon area and is suitable for implementation in various integrated digital controllers for high-frequency low-power switch-mode power supplies (SMPS). The programmable characteristics can be achieved through the utilization of the inherent averaging effect of the delay line or of the other voltage-to-time conversion structures and through the adjustments of delay cells' propagation times or the effective voltage-to-time conversion ratio in alternative structures.
    Type: Application
    Filed: July 3, 2007
    Publication date: August 28, 2008
    Applicant: SIPEX CORPORATION
    Inventors: Amir Parayandeh, Aleksandar Prodic
  • Publication number: 20070195876
    Abstract: A hybrid digital pulse width modulator can have a delay line with digitally programmable delay cells. The digitally programmable delay cells can be adjusted by a digital correction signal from a delay matching circuit.
    Type: Application
    Filed: February 22, 2006
    Publication date: August 23, 2007
    Applicant: SIPEX Corporation
    Inventor: Aleksandar Prodic
  • Patent number: 7148669
    Abstract: The present invention provides a method for producing a controlled output voltage for a switching power converter under current control using pulse width modulation, the switching power converter including a predictive digital current-mode controller and a digital pulse width modulator. The current control results in an unstable output voltage, and the pulse width modulation method is selected to eliminate the instability of the output voltage.
    Type: Grant
    Filed: February 2, 2004
    Date of Patent: December 12, 2006
    Assignee: The Regents of the University of Colorado, a body corporate
    Inventors: Dragan Maksimovic, Jingquan Chen, Aleksandar Prodic, Robert W. Erickson
  • Publication number: 20060055574
    Abstract: A voltage controller (150), the controller comprising: a voltage comparator (700) operative to provide a digital error signal (152); a compensator (300) operative to determine a digital control signal (154) based on said provided error signal; and a modulator (400) operative to provide a power control signal (156) based on said determined digital control signal, wherein said comparator, said compensator, and said modulator are implemented entirely with digital logic gates.
    Type: Application
    Filed: December 9, 2002
    Publication date: March 16, 2006
    Inventors: Dragan Maksimovic, Benjamin Patella, Aleksandar Prodic, Sandeep Dhar
  • Publication number: 20050168198
    Abstract: The present invention provides a method for producing a controlled output voltage for a switching power converter under current control using pulse width modulation, the switching power converter including a predictive digital current-mode controller and a digital pulse width modulator. The current control results in an unstable output voltage, and the pulse width modulation method is selected to eliminate the instability of the output voltage.
    Type: Application
    Filed: February 2, 2004
    Publication date: August 4, 2005
    Applicant: The Regents Of The University Of Colorado, a body corporate
    Inventors: Dragan Maksimovic, Jingquan Chen, Aleksandar Prodic, Robert Erickson