Patents by Inventor Jifeng Qin

Jifeng Qin 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).

  • Patent number: 9496112
    Abstract: An electric device is disclosed. In an embodiment, the device includes an electric element having an element terminal and a conductive spring being deflected, the spring being electrically coupled to the element terminal by a fusible joint. The device further includes a switch including a first monitor terminal and a second monitor terminal, the switch having a state that is changeable between a first connection state, where the first monitor terminal and the second monitor terminal are electrically coupled, and a second connection state, where the first monitor terminal and the second monitor terminal are electrically decoupled, and wherein the electrical device is configured such that when the joint fuses, the spring relaxes, thereby decoupling the spring and the element terminal and changing the state of the switch.
    Type: Grant
    Filed: June 20, 2012
    Date of Patent: November 15, 2016
    Assignee: EPCOS AG
    Inventors: Jifeng Qin, Shaoyu Sun, Dongjian Song, Zhouquan He
  • Publication number: 20140292472
    Abstract: An electric device includes an electric element having an element terminal and a conductive spring being deflected. The spring is electrically coupled to the element terminal by a fusible joint. A switch includes a first monitor terminal and a second monitor terminal. The state of the switch is changeable between a first connection state, where the first monitor terminal and the second monitor terminal are electrically coupled, and a second connection state, where the first monitor terminal and the second monitor terminal are electrically decoupled. When the joint fuses, the spring relaxes, thereby decoupling the spring and the element terminal and changing the state of the switch.
    Type: Application
    Filed: June 20, 2012
    Publication date: October 2, 2014
    Applicant: EPCOS AG
    Inventors: Jifeng Qin, Shaoyu Sun, Dongjian Song, Zhouquan He
  • Patent number: 8723490
    Abstract: A system and method for regulating power flow and limiting inductor current in a bidirectional direct current (DC)-to-DC converter is provided. In one aspect, a feedback circuit is provided to control power flow and/or limit inductor current based on the input/output voltage and/or current conditions in the bidirectional DC-DC converter. During a boost mode of operation, the duty cycle of a low-side switch within the bidirectional DC-DC converter is reduced, based on an analysis of the high-side voltage and positive inductor current. Further, during a buck mode of operation, the duty cycle of the low-side switch is increased, based on an analysis of the low-side voltage and negative inductor current. Moreover, the duty cycle of the low-side switch is adjusted, such that, the high-side voltage, low-side voltage and inductor current (in both directions) do not exceed preset threshold and the bidirectional DC-DC converter returns to a steady state.
    Type: Grant
    Filed: August 1, 2011
    Date of Patent: May 13, 2014
    Assignee: intersil Americas Inc.
    Inventors: Zaki Moussaoui, Jifeng Qin, Joseph Buxton
  • Patent number: 8570769
    Abstract: An embodiment of a controller for a multidirectional signal converter is operable to cause the converter to regulate a first signal at a first converter node, and to have a switch timing that is independent of a direction of power transfer between the first converter node and a second converter node. For example, in an embodiment, such a controller may be part of a bidirectional voltage converter that handles power transfer between two loads. Such a voltage converter may have improved conversion efficiency and a smaller size and lower component count as compared to a conventional multidirectional voltage converter. Furthermore, such a voltage converter may be operable with a common switching scheme regardless of the direction of power transfer, and without the need for an indicator of the instantaneous direction of power flow.
    Type: Grant
    Filed: October 7, 2010
    Date of Patent: October 29, 2013
    Assignee: Intersil Americas LLC
    Inventors: Zaki Moussaoui, Jifeng Qin
  • Patent number: 8552699
    Abstract: An EMI reduction network for a converter, the converter including upper and lower power switches provided between an input voltage node and a reference node. An inductance is coupled between the input voltage node and the upper switch at a first node, a capacitance and an auxiliary power switch are coupled in series between the first and reference nodes, and a controller is provided to control switching. The controller switches the upper switch based on a PWM signal. The controller keeps the lower switch turned on until the phase node goes positive while the upper switch is on. The controller turns the auxiliary switch on after the lower power switch is turned off and turns the auxiliary switch off after the upper power switch is turned off. The lower and auxiliary switches may be zero voltage switched, and the upper switch may be zero current switched.
    Type: Grant
    Filed: November 1, 2011
    Date of Patent: October 8, 2013
    Assignee: Intersil Americas Inc.
    Inventors: Zaki Moussaoui, Jifeng Qin, Colm Brazil
  • Patent number: 8503194
    Abstract: An embodiment of a multidirectional signal converter includes first and second converter nodes, a transformer, and first and second stages. The transformer includes first and second windings, and the first stage is coupled between the first converter node and the first winding of the transformer. The second stage includes a first node coupled to the second converter node, a second node coupled to a node of the second winding of the transformer, and a filter node, is operable as a boost converter while current is flowing out from the second converter node, and is operable as a buck converter while current is flowing out from the first converter node. For example, in an embodiment, such a multidirectional signal converter may be a bidirectional voltage converter that handles power transfer between two loads. Such a voltage converter may have improved conversion efficiency and a smaller size and lower component count as compared to a conventional multidirectional voltage converter.
    Type: Grant
    Filed: October 7, 2010
    Date of Patent: August 6, 2013
    Assignee: Intersil Americas LLC
    Inventors: Zaki Moussaoui, Jifeng Qin
  • Patent number: 8441148
    Abstract: A DC to DC converter comprises voltage regulation circuitry for generating at least two output voltages responsive to an input voltage. The voltage regulation circuitry further includes a plurality of main switches connected to receive the input voltage. A plurality of auxiliary switches is connected to provide the at least two output voltages. A single inductor is connected between the plurality of main switches and the plurality of auxiliary switches. A dual-output PWM controller provides a first PWM control signal for controlling the operation of the plurality of main switches responsive to a first feedback voltage from a first output voltage using a first control loop and provides a second PWM control signal for controlling the operation of the plurality of auxiliary switches responsive to a second feedback voltage from a second output voltage using a second control loop. Current mode control can be used for each control loop to reduce the cross regulation problem.
    Type: Grant
    Filed: June 8, 2010
    Date of Patent: May 14, 2013
    Assignee: Intersil Americas LLC
    Inventors: Zaki Moussaoui, Jifeng Qin
  • Publication number: 20120262139
    Abstract: An EMI reduction network for a converter, the converter including upper and lower power switches provided between an input voltage node and a reference node. An inductance is coupled between the input voltage node and the upper switch at a first node, a capacitance and an auxiliary power switch are coupled in series between the first and reference nodes, and a controller is provided to control switching. The controller switches the upper switch based on a PWM signal. The controller keeps the lower switch turned on until the phase node goes positive while the upper switch is on. The controller turns the auxiliary switch on after the lower power switch is turned off and turns the auxiliary switch off after the upper power switch is turned off The lower and auxiliary switches may be zero voltage switched, and the upper switch may be zero current switched.
    Type: Application
    Filed: November 1, 2011
    Publication date: October 18, 2012
    Applicant: INTERSIL AMERICAS INC.
    Inventors: Zaki Moussaoui, Jifeng Qin, Colm Brazil
  • Patent number: 8274356
    Abstract: A resistor includes a ceramic body, metal electrodes on sides of the ceramic body, each of which is connected to an electrode lead, and an insulating layer contacting a metal electrode among the metal electrodes. The insulating layer is meltable in response to heat. A conductive connector contacts the insulating layer above the metal electrode and is configured to short the metal electrodes when the insulating layer melts.
    Type: Grant
    Filed: January 14, 2009
    Date of Patent: September 25, 2012
    Assignee: EPCOS (Zhuhai FTZ) Co., Ltd.
    Inventors: Jifeng Qin, Dongjian Song, Shaoyu Sun
  • Publication number: 20120049820
    Abstract: A system and method for reducing negative inductor current during soft start of a bidirectional direct current (DC)-to-DC converter is provided. Typically, the bidirectional DC-to-DC converter includes an active switch and a passive switch. The system employs a soft start circuit that controls the duty cycle of the passive switch during soft start of the active switch. In one aspect, the soft start circuit gradually increases the duty cycle of the passive switch from zero to a steady state value, and provides a soft start for the passive switch concurrently/simultaneously during the soft start of the active switch. Moreover, the soft start circuit disclosed herein can avoid the reverse transient inductor current during start-up, prevent system damage and make the design of the bidirectional DC-to-DC converter more robust.
    Type: Application
    Filed: April 26, 2011
    Publication date: March 1, 2012
    Applicant: INTERSIL AMERICAS INC.
    Inventors: Zaki Moussaoui, Jifeng Qin, Joseph Buxton
  • Publication number: 20120049772
    Abstract: A system and method for regulating power flow and limiting inductor current in a bidirectional direct current (DC)-to-DC converter is provided. In one aspect, a feedback circuit is provided to control power flow and/or limit inductor current based on the input/output voltage and/or current conditions in the bidirectional DC-DC converter. During a boost mode of operation, the duty cycle of a low-side switch within the bidirectional DC-DC converter is reduced, based on an analysis of the high-side voltage and positive inductor current. Further, during a buck mode of operation, the duty cycle of the low-side switch is increased, based on an analysis of the low-side voltage and negative inductor current. Moreover, the duty cycle of the low-side switch is adjusted, such that, the high-side voltage, low-side voltage and inductor current (in both directions) do not exceed preset threshold and the bidirectional DC-DC converter returns to a steady state.
    Type: Application
    Filed: August 1, 2011
    Publication date: March 1, 2012
    Applicant: INTERSIL AMERICAS INC.
    Inventors: Zaki Moussaoui, Jifeng Qin, Joseph Buxton
  • Publication number: 20110187189
    Abstract: A DC to DC converter comprises voltage regulation circuitry for generating at least two output voltages responsive to an input voltage. The voltage regulation circuitry further includes a plurality of main switches connected to receive the input voltage. A plurality of auxiliary switches is connected to provide the at least two output voltages. A single inductor is connected between the plurality of main switches and the plurality of auxiliary switches. A dual-output PWM controller provides a first PWM control signal for controlling the operation of the plurality of main switches responsive to a first feedback voltage from a first output voltage using a first control loop and provides a second PWM control signal for controlling the operation of the plurality of auxiliary switches responsive to a second feedback voltage from a second output voltage using a second control loop. Current mode control can be used for each control loop to reduce the cross regulation problem.
    Type: Application
    Filed: June 8, 2010
    Publication date: August 4, 2011
    Applicant: INTERSIL AMERICAS INC.
    Inventors: ZAKI MOUSSAOUI, JIFENG QIN
  • Publication number: 20110149611
    Abstract: An embodiment includes coupling a first intermediate node between a first inductor and a first winding of a transformer to a reference node during a first portion of a first switching cycle, uncoupling the first intermediate node from the reference node and coupling the first intermediate node to a signal-storage element during a second portion of the first switching cycle, coupling a second winding of the transformer between the reference node and a second converter node during the second portion of the first switching cycle, and regulating a signal at the second converter node by controlling a duration of one of the first and second portions of the first switching cycle. For example, in an embodiment, bidirectional signal converter may perform the above steps to handle power transfer between two loads. Such a voltage converter may have improved conversion efficiency and a smaller size and lower component count as compared to a conventional bidirectional voltage converter.
    Type: Application
    Filed: October 7, 2010
    Publication date: June 23, 2011
    Applicant: INTERSIL AMERICAS INC.
    Inventors: Zaki MOUSSAOUI, Jifeng QIN
  • Publication number: 20110149609
    Abstract: An embodiment of a controller for a multidirectional signal converter is operable to cause the converter to regulate a first signal at a first converter node, and to have a switch timing that is independent of a direction of power transfer between the first converter node and a second converter node. For example, in an embodiment, such a controller may be part of a bidirectional voltage converter that handles power transfer between two loads. Such a voltage converter may have improved conversion efficiency and a smaller size and lower component count as compared to a conventional multidirectional voltage converter. Furthermore, such a voltage converter may be operable with a common switching scheme regardless of the direction of power transfer, and without the need for an indicator of the instantaneous direction of power flow.
    Type: Application
    Filed: October 7, 2010
    Publication date: June 23, 2011
    Applicant: INTERSIL AMERICAS INC.
    Inventors: Zaki MOUSSAOUI, Jifeng QIN
  • Publication number: 20110149610
    Abstract: An embodiment of a multidirectional signal converter includes first and second converter nodes, a transformer, and first and second stages. The transformer includes first and second windings, and the first stage is coupled between the first converter node and the first winding of the transformer. The second stage includes a first node coupled to the second converter node, a second node coupled to a node of the second winding of the transformer, and a filter node, is operable as a boost converter while current is flowing out from the second converter node, and is operable as a buck converter while current is flowing out from the first converter node. For example, in an embodiment, such a multidirectional signal converter may be a bidirectional voltage converter that handles power transfer between two loads. Such a voltage converter may have improved conversion efficiency and a smaller size and lower component count as compared to a conventional multidirectional voltage converter.
    Type: Application
    Filed: October 7, 2010
    Publication date: June 23, 2011
    Applicant: INTERSIL AMERICAS INC.
    Inventors: Zaki MOUSSAOUI, Jifeng QIN
  • Publication number: 20110057763
    Abstract: A new voltage dependent resistor with overheated protection structure. The said voltage dependent resistor includes a ceramic body. Metal electrodes are set at the two opposite sides of the ceramic body, and each of the metal electrodes is connected to one electrode lead. The said voltage dependent resistor further includes a conductive connector structure which can connect the two metal electrodes when a heat-fusing insulating layer that is set between the conductive IN connector structure and the metal electrodes is melt down.
    Type: Application
    Filed: January 14, 2009
    Publication date: March 10, 2011
    Inventors: Jifeng Qin, Dongjian Song, Shaoyu Sun
  • Publication number: 20100301826
    Abstract: A multiphase boost converter includes a multiphase PWM controller for generating a plurality of PWM signals. A plurality of boost converters are each associated with a separate phase connected between an input voltage node and an output voltage node and generating an output voltage responsive to an input voltage and the plurality of PWM signals. Phase nodes of each of the plurality of boost converters are ORed to each other.
    Type: Application
    Filed: December 31, 2009
    Publication date: December 2, 2010
    Applicant: INTERSIL AMERICAS INC.
    Inventors: ZAKI MOUSSAOUI, JIFENG QIN, SITTHIPONG ANGKITITRAKUL