Patents by Inventor Oscar Persson

Oscar Persson 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: 20150180343
    Abstract: A method and a control unit for changing a working mode of a synchronous rectifier. The synchronous rectifier comprises at least one controllable switch having a diode in parallell thereof. The synchronous rectifier is operatively connected to a reactive circuit, and is arranged to receive at least one control signal at a control terminal, for controlling at least one controllable switch. The at least one control signal is pulse-width modulated with a defined duty-cycle. The method comprises adjusting the pulse-width of the at least one control signal between zero percent duty-cycle and the defined duty-cycle at a frequency above a cut-off frequency of the reactive circuit. Thereby, reducing the effect of a forward voltage drop over said diode in the synchronous rectifier.
    Type: Application
    Filed: July 27, 2012
    Publication date: June 25, 2015
    Inventors: Oscar Persson, Xuefeng Yang, Magnus Karlsson
  • Publication number: 20150138844
    Abstract: A control circuit operable to control the switching of switching elements in a switched mode power supply. The control circuit comprises a switching control signal generator operable to generate control signals for switching the switching elements such that the switched mode power supply converts an input voltage (Vin) to an output voltage Vout). The control circuit further comprises an operation mode setting module which is operable to receive a signal (I) indicative of a current flowing to a load that is connected to an output of the switched mode power supply, and operable to cause the switching control signal generator to generate the control signals so as to operate the switched mode power supply in a continuous conduction mode or a pulse skipping mode in dependence upon the current.
    Type: Application
    Filed: July 13, 2012
    Publication date: May 21, 2015
    Inventors: Magnus Karlsson, Oscar Persson
  • Publication number: 20150109825
    Abstract: A control circuit (200) operable to generate a control signal (D) to control the duty cycle of a switched mode power supply (100). The control circuit (200) comprises a reference signal generator (210) operable to receive a signal indicative of an input voltage (Vin) of the switched mode power supply (100) and generate a reference signal (VR) that is a function of the input voltage (Vin), and an offset reference signal generator (220) operable to generate an offset reference signal (VR—offset) “by’ combining the reference signal (VR) with an offset signal (Voffset), the offset signal (Voffset) being independent of the input voltage (Vin), The control circuit (200) further comprises an error signal, generator (230) arranged to receive a signal indicative of an output voltage (Vout) of the switched mode power supply (100) and operable to generate an error signal (VE) based on the offset reference signal (VR—offset) and based on the output voltage (Vout).
    Type: Application
    Filed: April 20, 2012
    Publication date: April 23, 2015
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventors: Magnus Karlsson, Oscar Persson
  • Publication number: 20150055375
    Abstract: A control circuit, that controls the duty cycle of a switched mode power supply, comprises a reference voltage generator that, responsive to the input voltage exceeding a threshold value, generates a predetermined reference signal. Responsive to the input voltage not exceeding the threshold value, the reference voltage generator receives a signal indicative of an input voltage of the switched mode power supply and generates a variable reference signal dependent upon the input voltage. The control circuit further comprises an error signal generator that receives a signal indicative of an output voltage of the power supply and generates an error signal based on the reference signal generated by the reference voltage generator and based on the output voltage. The control circuit also includes a duty cycle control signal generator that generates the control signal to control the duty cycle of the power supply in dependence upon the error signal.
    Type: Application
    Filed: January 30, 2012
    Publication date: February 26, 2015
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventors: Magnus Karlsson, Oscar Persson
  • Patent number: 8964416
    Abstract: A power supply and method for reliable turn-on of a switched mode power supply (SMPS) in which the same transformer is used for providing power from the primary side to both the main output of the SMPS and a secondary side voltage regulator a train of voltage pulses are transmitted, from the primary side to the secondary side. The voltage regulator generates a feedback signal indicating when it has turned on and is operating, and the transmission of pulses within the train is controlled based on the detection of feedback signal. In this way, only the required amount of power to switch on the voltage regulator is transferred to the secondary side during a start-up operation and excess power at the main output is prevented, thereby avoiding distortion of the desired start-up ramp figure.
    Type: Grant
    Filed: March 30, 2010
    Date of Patent: February 24, 2015
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Oscar Persson, Mikael Appelberg
  • Publication number: 20150028843
    Abstract: The present disclosure relates to methods, systems and a module for operating a power converter module, the power converter module comprises a voltage source, a remote control terminal configured to be connected to a voltage potential for remote control of the power converter module. A voltage converter is configured to send an alarm signal, determine the voltage potential of the remote control terminal, and control an output voltage of the voltage converter at an output terminal of the power converter module based on the determined voltage potential of the remote control terminal. An alarm branch is configured to change the voltage potential of the remote control terminal by a voltage source in response to an alarm signal from the voltage converter when the remote control terminal is connected to a voltage potential, thereby causing the voltage converter to control the output voltage at the output terminal.
    Type: Application
    Filed: March 1, 2012
    Publication date: January 29, 2015
    Applicant: Telefonaktiebolaget L.M. Ericsson (publ)
    Inventors: Magnus Karlsson, Oscar Persson
  • Publication number: 20150003116
    Abstract: A control circuit generates a control signal to control a duty cycle of a switched mode power supply such that the magnetic flux density in the transformer is balanced, thereby preventing saturation of the transformer core. This permits the use of unsymmetrical duty cycles within the switch cycle. The control circuit comprises a flux density calculator and a regulator. The flux density regulator receives a signal indicative of the input voltage of the switched mode power supply and a feedback signal comprising the generated control signal, and it generates therefrom an average flux density signal. The regulator receives the generated average flux density signal and a signal indicative of the output voltage of the switched mode power supply, and generates the control signal in dependence upon the average flux density signal, the reference flux density signal, the signal indicative of the output voltage and a reference voltage signal.
    Type: Application
    Filed: February 9, 2012
    Publication date: January 1, 2015
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventors: Magnus Karlsson, Mikael Appelberg, Oscar Persson
  • Publication number: 20140327414
    Abstract: The present disclosure relates to methods, a system and a module for operating a power converter module. The power converter module comprises a voltage converter, an output circuitry and a processing circuitry operable for controlling the voltage converter. One method comprises transmitting a first status signal representing operating parameters of the voltage converter to the processing circuitry. Determining whether the first status signal of the voltage converter is acceptable. The method also comprises transmitting a second status signal representing the operating parameters of the output circuitry to the processing circuitry. The method also comprises determining if the second status signal is above a predetermined threshold value. When the second status signal is above said predetermined threshold value and the status of the voltage converter is acceptable, entering a peak output mode operating the voltage converter at maximum power dissipation.
    Type: Application
    Filed: December 9, 2011
    Publication date: November 6, 2014
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventors: Oscar Persson, Magnus Karlsson, Jonas Malmberg
  • Publication number: 20140293662
    Abstract: A switched mode power supply (SMPS) is disclosed in which a simple primary side controller is used to send a single pulse of energy to the secondary side to switch on an output voltage controller. The pulse is sent across the main power train and a filtering arrangement is provided on the secondary side to minimise the energy at the output of the SMPS while maximising the energy supplied to the output voltage controller. Advantageously, the SMPS is configured such that the maximum amount of energy transferred from the primary side to the secondary side during a start-up operation is inherently limited. Protection against short circuit conditions and malfunctions is therefore provided without requiring complicated circuitry.
    Type: Application
    Filed: April 15, 2011
    Publication date: October 2, 2014
    Applicant: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Oscar Persson, Mikael Appelberg, Marko Leskovec
  • Publication number: 20140167901
    Abstract: A multi-layered printed circuit board, PCB, includes first windings for a first side of a planar magnetic transformer and second windings for a second side of the planar magnetic transformer. The PCB further includes conductive layers configured as the first windings, conductive layers configured as the second windings, and layers of an isolation material. Each layer of the isolation material is arranged between two conductive layers to provide electrical isolation between the two conductive layers. A group of two or more adjacent conductive layers are all conductive layers of the first windings and are all arranged between two conductive layers of the second windings. The thickness of the isolation material between the group of adjacent conductive layers of the first windings is less than the thickness of the isolation material between a conductive layer of the second windings and a conductive layer of the first windings.
    Type: Application
    Filed: December 19, 2012
    Publication date: June 19, 2014
    Applicant: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Oscar Persson, Magnus Karlsson
  • Publication number: 20130343094
    Abstract: A control circuit for a switched mode power supply (SMPS) has an input voltage reference voltage generator arranged to receive a signal indicative of an input voltage of the SMPS and is arranged to generate a reference signal directly proportional to the input voltage. An error signal generator of the control circuit is arranged to receive a signal indicative of an output voltage of the SMPS and arranged to generate an error signal based on the reference signal generated by the input reference voltage generator and based on the output voltage of the SMPS. A duty cycle control signal generator of the control circuit is arranged to generate a control signal, to control the duty cycle of the SMPS, in dependence upon the error signal.
    Type: Application
    Filed: March 3, 2011
    Publication date: December 26, 2013
    Inventors: Magnus Karlsson, Anders Kullman, Fredrik Wahledow, Henrik Borgengren, Jonas Malmberg, Oscar Persson
  • Publication number: 20130294111
    Abstract: A switched mode power supply includes a switching device, the switched mode power supply being operable to convert an input voltage (Vin) to an output voltage (Vout) by switching the switching device, and a voltage regulator operable to generate a feedback signal based on at least one of the output voltage and an output current of the switched mode power supply. The power supply further comprises an overload detector, which is arranged to receive the feedback signal and operable to determine whether the feedback signal is outside a predetermined range. If the feedback signal is outside the predetermined range, the overload detector is operable to determine that the switched mode power supply is in an overload state, and when an overload state is determined, perform control to place the switched mode power supply in a non-operational state.
    Type: Application
    Filed: November 11, 2010
    Publication date: November 7, 2013
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventors: Oscar Persson, Mikael Appelberg
  • Publication number: 20130155727
    Abstract: An isolated switched mode power supply comprises a transformer, with primary and secondary windings, and a rectification network connected to the secondary winding. The rectification network and the transformer are arranged such that, during a free-wheeling period of operation of the switched mode power supply, a magnetic flux from a first portion of a secondary winding of the transformer substantially cancels a magnetic flux from a second portion of the secondary winding between the first and second portions of the secondary winding. Additionally, a secondary side circuit connected to the secondary winding comprises a switching device, which is connected to a centre-tap, provided between the first and second portions of the secondary winding, and an output of the rectification network so as to conduct at least a part of a free-wheeling current flowing in the secondary side circuit during the free-wheeling period.
    Type: Application
    Filed: September 2, 2010
    Publication date: June 20, 2013
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventors: Magnus Karlsson, Jonas Malmberg, Oscar Persson
  • Publication number: 20130003422
    Abstract: A power supply and method for reliable turn-on of a switched mode power supply (SMPS) in which the same transformer is used for providing power from the primary side to both the main output of the SMPS and a secondary side voltage regulator a train of voltage pulses are transmitted, from the primary side to the secondary side. The voltage regulator generates a feedback signal indicating when it has turned on and is operating, and the transmission of pulses within the train is controlled based on the detection of feedback signal. In this way, only the required amount of power to switch on the voltage regulator is transferred to the secondary side during a start-up operation and excess power at the main output is prevented, thereby avoiding distortion of the desired start-up ramp figure.
    Type: Application
    Filed: March 30, 2010
    Publication date: January 3, 2013
    Applicant: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Oscar Persson, Mikael Appelberg
  • Publication number: 20120319504
    Abstract: To reduce power loss in an intermediate bus architecture power system, embodiments of the present invention provide an intermediate bus converter which converts an input voltage to an intermediate bus voltage using a converting unit; receives a signal indicative of an output of a converting unit; determines an intermediate bus voltage to reduce power loss in dependence upon the signal indicative of an output of the converting unit; generates a control signal to control the converting unit to convert the input voltage to the determined intermediate bus voltage; and generates an intermediate bus voltage in dependence upon the control signal.
    Type: Application
    Filed: April 20, 2011
    Publication date: December 20, 2012
    Inventors: Jonas Malmberg, Anders Kullman, Fredrik Wahledow, Henrik Borgengren, Magnus Karlsson, Oscar Persson