Having Current Protection Patents (Class 363/56.1)
  • Patent number: 9276490
    Abstract: Embodiments herein relate to setting a voltage of an adapter (100, 200). In an embodiment, the adapter is to measure a current output by the adapter, compare the measured current at the adapter to a first current and to output a DC voltage. The adapter is to set a level of the DC voltage output by the adapter based on the comparison.
    Type: Grant
    Filed: March 9, 2011
    Date of Patent: March 1, 2016
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Lee Warren Atkinson
  • Patent number: 9136767
    Abstract: A switching power-supply device comprises: a transformer; a switching element connected in series with a primary coil; an output voltage generation circuit to generate an output voltage from a voltage generated in a secondary coil; a control circuit power-supply-voltage generation circuit to generate a power-supply voltage from a voltage generated in an auxiliary coil; a feedback control circuit to control an ON width of the switching element by using the voltage generated in the auxiliary coil; a voltage reduction detection circuit to output a pulse signal to the secondary coil when a reduction of the output voltage is detected; a voltage-reduction-signal detection circuit to detect the voltage reduction signal transmitted to the primary coil from the secondary coil; and a trigger circuit to output a trigger signal to turn on the switching element when the voltage reduction signal is detected by the voltage-reduction-signal detection circuit.
    Type: Grant
    Filed: September 26, 2013
    Date of Patent: September 15, 2015
    Assignee: Sanken Electric Co., LTD.
    Inventors: Takeki Sugahara, Tetsuya Tabata, Takashi Matsumoto, Masao Ueno
  • Patent number: 9036383
    Abstract: In some aspects of the invention, overcurrent protection is carried out by suppressing fluctuations in current flowing through a switching element after overcurrent detection. A peak current reaching time detection circuit detects a peak current reaching time needed until current flowing through a switching element reaches a peak value. A difference voltage detection circuit, including a ½ time detection circuit which detects a time of ½ an ON time of the preceding cycle of the switching element, detects difference voltage between reference voltage used when detecting overcurrent flowing to a load and a signal which has detected current flowing through the switching element for the ½ time. A delay time adjustment circuit, based on at least one of the peak current reaching time and difference voltage, carries out adjustment and control of a delay time occurring until the time when the switching element is turned off after detecting the overcurrent.
    Type: Grant
    Filed: September 11, 2013
    Date of Patent: May 19, 2015
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventor: Jun Yabuzaki
  • Patent number: 8884577
    Abstract: In a control apparatus for a rotary electric machine receiving power from a DC power supply, a DC-AC converting circuit is provided with serially connected circuits each having high-potential-side and low-potential-side switching elements. When a short-circuit occurs at the switching elements, all the switching elements are turned OFF for failsafe and a path connecting the machine and the battery is opened. In such a case, a switching element belonging to part of the switching elements is turned ON, with potential at all the terminals of the rotary electric machine being the same. A location of the short-circuit occurs is identified, based on changes in current passing through the machine and being detected in response to turning ON the switching element. The changes are at least one of a reduction change in deviation of the current from a zero point and a reduction change in an absolute value of the current.
    Type: Grant
    Filed: September 16, 2011
    Date of Patent: November 11, 2014
    Assignee: Denso Corporation
    Inventor: Hiroya Tsuji
  • Patent number: 8804385
    Abstract: A switching converter IC without a built-in power switching device includes a first terminal serving as a power supply positive connection, a second terminal serving as a power supply return connection, a third terminal serving as the switch-driving connection for controlling the switching duty of an external bipolar or MOSFET power switching device and also serving as a conduit for detection of current drawn by the power switching device to thereby provide overcurrent protection. Feedback information is derived from voltage between the first and the second terminals.
    Type: Grant
    Filed: August 8, 2011
    Date of Patent: August 12, 2014
    Assignee: Mosway Semiconductor Limited
    Inventors: Chiu-Sing Celement Tse, On-Bon Peter Chan, Chik-Yam Lee, Chi-Keung Tang, Chi-Ken Kenny Lee
  • Patent number: 8749999
    Abstract: A controller of a power converter is provided. The controller includes a feedback circuit, an output circuit, and a clamping circuit. The feedback circuit generates a feedback signal in accordance with output of the power converter. The output circuit generates a switching signal in accordance with the feedback signal for regulating the output of the power converter. The clamping circuit limits the feedback signal under a first level for a first load condition and limits the feedback signal under a second level for a second load condition. The clamping circuit includes a timer circuit. The timer circuit determines a slew rate of the feedback signal for increasing the feedback signal from the first level to the second level, and the second level is higher than the first level.
    Type: Grant
    Filed: January 5, 2012
    Date of Patent: June 10, 2014
    Assignee: System General Corporation
    Inventors: Ta-Yung Yang, Keun-Eul Hong, Jung-Sheng Chen, Ju-hyun Kim
  • Patent number: 8665620
    Abstract: A timing circuit of a controller generates a clock signal having a switching period for use by a pulse width modulation (PWM) circuit to control a switch of a power supply. The switching period of the clock signal is based on a charging time plus a discharging time of a capacitor included in the timing circuit. A first current source charges the capacitor while the timing circuit is in a normal charging mode. A second current source charges the capacitor while the timing circuit is in an alternative charging mode that is when the on time of the switch exceeds a threshold time. The current provided by the second current source is less than the current provided by the first current source such that the switching period of the clock signal is increased in response to the timing circuit entering the alternative charging mode.
    Type: Grant
    Filed: August 20, 2013
    Date of Patent: March 4, 2014
    Assignee: Power Integrations, Inc.
    Inventors: Stefan Bäurle, Guangchao Zhang, Arthur B. Odell, Edward E. Deng
  • Patent number: 8630104
    Abstract: A switching power supply has a function of improving a power factor, and outputs insulated DC. The switching power supply performs two kinds of controls for switching devices exclusive to each other: controlling of a switching device provided in a direction in which the discharging of a primary-side smoothing capacitor is prohibited at the time of suspension of commercially available AC power and near the zero cross of an input voltage; and causing a switching device provided between the output side of a third winding and the primary-side smoothing capacitor to control a charging current, thereby charging a capacitor in a boosted manner.
    Type: Grant
    Filed: August 25, 2011
    Date of Patent: January 14, 2014
    Assignee: TKR Corporation
    Inventors: Takayuki Ouchi, Minoru Moteki, Akihiko Kanouda
  • Patent number: 8630102
    Abstract: A power converter includes a dc input having first and second terminals. A main converter is coupled to the first terminal of the dc input. A standby circuit coupled to the second terminal of the dc input and the main converter. The main converter is coupled to control a transfer of energy from the dc input through the standby circuit to a main output of the main converter during a normal operating condition of the power supply. The standby circuit is coupled to decouple the main converter from the second terminal of the dc input during a standby operating condition of the power converter. A standby converter is coupled to the first and second terminals of the dc input to control a transfer of energy from the dc input to a standby output of the standby converter during the standby operating condition of the power converter.
    Type: Grant
    Filed: January 8, 2013
    Date of Patent: January 14, 2014
    Assignee: Power Integrations, Inc.
    Inventors: Balu Balakrishnan, David Michael Hugh Matthews
  • Patent number: 8625316
    Abstract: A neutral point clamped (NPC) power converter fault protection system is provided, and include a DC bus, a switching network, and a control module. The switching network is connected to the DC bus. The switching network includes at least two leg circuits. Each of the at least two leg circuits includes at least two switches connected in series and two NPC diodes. Each of the two NPC diodes corresponds to one of the at least two switches. Each of the at least two switches has an open position. The two NPC diodes are connected between a corresponding one of the at least two leg circuits and the DC bus. The control module is in communication with the switching network. The control module includes control logic for monitoring the switching network to detect a fault condition.
    Type: Grant
    Filed: December 9, 2011
    Date of Patent: January 7, 2014
    Assignee: General Electric Company
    Inventors: Petar Jovan Grbovic, Mathieu Giroux
  • Patent number: 8619440
    Abstract: Control methods and controller thereof for a power supply including a power switch and an inductor. The power switch is turned on to increase the inductor current through the inductor, which is sensed to generate a current-sense signal. The current-sense signal is added up with an adjusting signal to generate a summation signal. The power switch is turned off if the summation signal is higher than a peak limit. The turn-on time of the power switch is detected to update the adjusting signal.
    Type: Grant
    Filed: September 20, 2011
    Date of Patent: December 31, 2013
    Assignee: Leadtrend Technology Corp.
    Inventors: Kuo-Chien Huang, Ren-Yi Chen, Wen-Chung Yeh
  • Publication number: 20130336029
    Abstract: System and method for protecting a power converter. The system includes a duty-cycle detection component configured to receive a modulation signal, determine a first duty cycle corresponding to a first period of the modulation signal, compare the first duty cycle with a threshold duty cycle, and generate a duty-cycle comparison signal. Additionally, the system includes a threshold generator configured to receive the duty-cycle comparison signal and generate a threshold signal corresponding to a second period of the modulation signal, the second period being after the first period, and a comparator configured to receive the threshold signal and a first signal and to generate a first comparison signal. The first signal is associated with an input current for a power converter. Moreover, the system includes a pulse-width-modulation component configured to receive the first comparison signal and generate the modulation signal for adjusting the input current for the power converter.
    Type: Application
    Filed: August 14, 2013
    Publication date: December 19, 2013
    Applicant: On-Bright Electronics (Shanghai) Co., Ltd.
    Inventors: Yaming Cao, Jinya Dong, Yunchao Zhang, Lieyi Fang
  • Patent number: 8611116
    Abstract: An example integrated circuit controller for use in a switching power supply includes a pulse width modulation (PWM) circuit and a timing circuit. The PWM circuit controls a switch to regulate an output of the power supply in response to a switch current flowing through the switch and in response to a clock signal having a switching period. The timing circuit provides the clock signal and increases the switching period in response to an on time of the switch exceeding a threshold time.
    Type: Grant
    Filed: July 28, 2011
    Date of Patent: December 17, 2013
    Assignee: Power Integrations, Inc.
    Inventors: Stefan Bäurle, Guangchao Darson Zhang, Arthur B. Odell, Mingming Mao, Michael Yue Zhang, Edward Deng
  • Patent number: 8587284
    Abstract: A power supply includes an energy transfer element, a switch, and a controller. The controller includes a modulator, a drive signal generator, a comparator, and a variable current limit generator. The modulator generates an enable signal having logic states responsive to a feedback signal. The drive signal generator either enables or skips enabling a switch of the power supply during a switching period in response to the logic state of the enable signal. The comparator asserts an over current signal to disable the switch if the switch current exceeds a variable current limit. The variable current limit generator sets the variable current limit to a first current limit in response to one logic state of the enable signal and sets the variable current limit to a second current limit if the enable signal transitions logic states and the over current signal is asserted during the switching period.
    Type: Grant
    Filed: February 28, 2012
    Date of Patent: November 19, 2013
    Assignee: Power Integrations, Inc.
    Inventors: Alex B. Djenguerian, Stefan Bäurle, Kent Wong
  • Patent number: 8575885
    Abstract: To make it possible to avoid an unstable state with a simple configuration even one of the phases of the motor fails. A motor drive system in accordance with the present invention includes a motor to which a plurality of phase coils of five phases or more are connected in a star connection, an inverter connected to one end of each of the phase coils, the inverter being configured to convert a DC power into an AC power and supply the AC power to each phase of the motor, a power relay disposed at another end of each of the phase coils, the power relay being configured so as to be able to cut off a supply power to at least one phase coil among the plurality of phase coils of the motor by using a plurality of contact points interposed between the star-connected coils, and a control unit that generates a control signal for the inverter and thereby controls driving of the motor.
    Type: Grant
    Filed: January 25, 2010
    Date of Patent: November 5, 2013
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventor: Yoshihiro Okumatsu
  • Patent number: 8570771
    Abstract: System and method for regulating an output voltage of a power conversion system. The system includes an error amplifier coupled to a capacitor. The error amplifier is configured to receive a reference voltage, a first voltage, and an adjustment current and to generate a compensation voltage with the capacitor. The first voltage is associated with a feedback voltage. Additionally, the system includes a current generator configured to receive the compensation voltage and generate the adjustment current and a first current, and a signal generator configured to receive the first current and a second current. The signal generator is further configured to receive a sensing voltage and to generate a modulation signal. Moreover, the system includes the gate driver directly or indirectly coupled to the signal generator and configured to generate a drive signal based on at least information associated with the modulation signal.
    Type: Grant
    Filed: October 31, 2012
    Date of Patent: October 29, 2013
    Assignee: On-Bright Electronics (Shanghai) Co., Ltd.
    Inventors: Xiaomin Huang, Lieyi Fang
  • Patent number: 8531853
    Abstract: An example integrated circuit controller includes a pulse width modulation (PWM) circuit and a timing circuit. The PWM circuit controls a switch to regulate an output of a power supply in response to a switch current flowing through the switch and in response to a clock signal having a switching period. The timing circuit provides the clock signal and includes a timing capacitor where the switching period of the clock signal is equal to a charging time that the timing capacitor charges to an upper reference voltage plus a discharging time that the timing capacitor discharges to a lower reference voltage. The timing circuit increases the charging time of the timing capacitor by decreasing a rate at which the timing capacitor is charged to increase the switching period of the clock signal if an on time of the switch is greater than or equal to a threshold time.
    Type: Grant
    Filed: July 28, 2011
    Date of Patent: September 10, 2013
    Assignee: Power Integrations, Inc.
    Inventors: Stefan Bäurle, Guangchao Darson Zhang, Arthur B. Odell, Edward Deng
  • Patent number: 8482946
    Abstract: System and method for protecting a power converter. A system includes a threshold generator configured to generate a threshold signal, and a first comparator configured to receive the threshold signal and a first signal and to generate a comparison signal. The first signal is associated with an input current for a power converter. Additionally, the system includes a pulse-width-modulation generator configured to receive the comparison signal and generate a modulation signal in response to the comparison signal, and a switch configured to receive the modulation signal and adjust the input current for the power converter. The threshold signal is associated with a threshold magnitude as a function of time. The threshold magnitude increases with time at a first slope during a first period, and the threshold magnitude increases with time at a second slope during a second period. The first slope and the second slope are different.
    Type: Grant
    Filed: August 8, 2011
    Date of Patent: July 9, 2013
    Assignee: On-Bright Electronics (Shanghai) Co., Ltd.
    Inventors: Lieyi Fang, Shifeng Zhao, Bo Li, Zhiliang Chen
  • Patent number: 8472217
    Abstract: A switching mode power supply with a multi-mode controller is provided. The switching mode power supply may include a transformer having a primary winding and a secondary winding to supply power to a load. A feedback circuit may be included to generate a feedback signal that varies in relation to the load on the secondary winding. The multi-mode controller may include a switching circuit, a frequency control circuit and a current limiting circuit. The switching circuit may be coupled to the primary winding to control current flow through the primary winding. The frequency control circuit may control a switching frequency of the switching circuit based on the feedback signal. The current limiting circuit may limit current flow through the primary winding by causing the switching circuit to suspend current flow through the primary winding when the current reaches a peak current limit that is set based on the feedback signal.
    Type: Grant
    Filed: March 9, 2010
    Date of Patent: June 25, 2013
    Assignee: Monolithic Power Systems, Inc.
    Inventors: En Li, Junming Zhang, Yuancheng Ren
  • Patent number: 8416593
    Abstract: A switching power supply includes a rectifier circuit, a converter, a detecting unit, a control unit, a switching unit, and a protection unit. The rectifier circuit is used for rectifying an input voltage into a first direct current voltage. The converter is configured for generating a first current according to the first direct current voltage. The detecting unit is used for generating a detected voltage according to the first current. The control unit is configured for generating a control signal. The switching unit is used for enabling the converter, and conducting the first current to the detecting unit when receiving the control signal. The protection unit is configured for shunting the first current with the detecting unit when the first current becomes a large current surge. The control unit stops generating the control signal when determining that the detected voltage is equal to or higher than a predetermined value.
    Type: Grant
    Filed: December 9, 2008
    Date of Patent: April 9, 2013
    Assignees: Hong Fu Jin Precision Industry (ShenZhen) Co., Ltd., Hon Hai Precision Industry Co., Ltd.
    Inventors: Yong Xiong, Yong-Song Shi, Yong Li, Tao Wang
  • Patent number: 8369111
    Abstract: A power converter with low power consumption during a standby operating condition. An example power controller includes a main converter coupled to a dc input of the power converter to control a transfer of energy from the dc input of the power converter to a main output of the power converter. A standby converter is also included and is coupled to the dc input of the power converter to control a transfer of energy from the dc input of the power converter to a standby output of the power converter during a standby operating condition of the power converter. A standby circuit is also included and is coupled to the dc input of the power converter and coupled to the main converter. The standby circuit decouples the main converter from the dc input of the power converter during the standby operating condition of the power converter.
    Type: Grant
    Filed: August 2, 2010
    Date of Patent: February 5, 2013
    Assignee: Power Integrations, Inc.
    Inventors: Balu Balakrishnan, David Michael Hugh Matthews
  • Patent number: 8368433
    Abstract: The present invention discloses a transistor driving module, coupling to a converting controller, to driving a high side transistor and a low side transistor connected in series, wherein one end of the high side transistor is coupled to an input voltage and one end of the low side transistor is grounded. The transistor driving module comprises a high side driving unit, a low side driving unit, a current limiting unit and an anti-short through unit. The high side driving unit generates a high side driving signal to turn the high side transistor on according to a duty cycle signal, and the low side driving unit generates a low side driving signal turn the low side transistor on according to the high side driving signal. The current limiting unit is coupled to the high side transistor and the high side driving unit, and generates a current limiting signal when a current flowing through the high side transistor higher than a current limiting value.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: February 5, 2013
    Assignee: Green Solution Technology Co., Ltd.
    Inventors: Li-Min Lee, Shian-Sung Shiu, Chung-Che Yu, Si-Min Wu
  • Patent number: 8358518
    Abstract: A switching regulator of a power converter is provided and includes a feedback-input circuit, a programming circuit, and a peak-current-threshold circuit. The feedback-input circuit is coupled to a terminal of the switching regulator for receiving a feedback signal. The feedback-input circuit is operated in a first range of a terminal signal. The programming circuit is coupled to the terminal for generating a programming signal. The programming signal is operated in a second range of the feedback signal. The peak-current-threshold circuit generates a threshold signal in accordance with the programming signal. The feedback signal is coupled to regulate the output of the power converter, and the threshold signal is coupled to limit a peak switching current of the power converter.
    Type: Grant
    Filed: March 29, 2010
    Date of Patent: January 22, 2013
    Assignee: System General Corporation
    Inventors: Ta-Yung Yang, Shao-Chun Huang, Chen-Hui Chan, Jenn-Yu G. Lin
  • Patent number: 8355267
    Abstract: Disclosed are methods of detection for output short circuit of a flyback power supply, which detect the current sense signal provided by a current sense resistor serially connected to a power switch of the flyback power supply, and thus quickly identify whether or not the flyback power supply suffers output short circuit.
    Type: Grant
    Filed: June 11, 2010
    Date of Patent: January 15, 2013
    Assignee: Richpower Microelectronics Corporation
    Inventors: Kun-Yu Lin, Yu-Ming Chen, Pei-Lun Huang
  • Patent number: 8351227
    Abstract: A switching controller for power converter comprises a current-sense circuit and a PWM circuit. The current-sense circuit receives high-voltage signal across a first switch to generate a current-sense signal. The PWM circuit generates a switching signal to control the first switch in response to the current-sense signal. The switching controller further comprises a delay circuit. The delay circuit receives the switching signal to generate a delayed switching signal. The current-sense signal and the high-voltage signal ramp up with the same slope during the delayed switching signal is enabled. The current-sense signal will be pulled down to a level of a ground reference during the delayed switching signal is disabled. A delay time provided by the delay circuit avoids the high-voltage signal at the instance which the first switch is being turned off being conducted to a first comparator and a second comparator via a second switch.
    Type: Grant
    Filed: March 9, 2010
    Date of Patent: January 8, 2013
    Assignee: System General Corp.
    Inventor: Wei-Hsuan Huang
  • Patent number: 8331112
    Abstract: System and method for regulating an output voltage of a power conversion system. The system includes an error amplifier coupled to a capacitor. The error amplifier is configured to receive a reference voltage, a first voltage, and an adjustment current and to generate a compensation voltage with the capacitor. The first voltage is associated with a feedback voltage. Additionally, the system includes a current generator configured to receive the compensation voltage and generate the adjustment current and a first current, and a signal generator configured to receive the first current and a second current. The signal generator is further configured to receive a sensing voltage and to generate a modulation signal. Moreover, the system includes the gate driver directly or indirectly coupled to the signal generator and configured to generate a drive signal based on at least information associated with the modulation signal.
    Type: Grant
    Filed: August 23, 2010
    Date of Patent: December 11, 2012
    Assignee: On-Bright Electronics (Shanghai) Co., Ltd.
    Inventors: Xiaomin Huang, Lieyi Fang
  • Patent number: 8300427
    Abstract: A power conversion apparatus and an over current protection (OCP) method thereof are provided. The OCP method includes generating a pulse-width-modulation (PWM) signal according to a loading status of an electronic device, so as to switch a power switch in the power conversion apparatus and thus making the power conversion apparatus providing an output voltage to the electronic device; generating an OCP reference signal with variable slope according to a feedback signal related to the loading status of the electronic device and a system operation voltage of a PWM controller chip in the power conversion apparatus that is used for generating the PWM signal; and comparing a sensing voltage corresponding to a current following through the power switch on a resistor, and the OCP reference signal with variable slope to determine whether to activate an OCP mechanism to control the PWM controller chip whether to generate the PWM signal.
    Type: Grant
    Filed: July 30, 2010
    Date of Patent: October 30, 2012
    Assignee: Power Forest Technology Corporation
    Inventors: Chih-Hsiung Hsu, Ju-Lin Chia
  • Patent number: 8254151
    Abstract: In a switched mode power supply, and in accordance with a method for operating a switched mode power supply, the magnitude of each occurrence of a current flowing during operation of a power output switch is sensed for negative feedback control. A sense voltage is generated proportional to the primary supply voltage. Whenever the sense voltage exceeds a threshold, output power of the power supply is limited by increasing the sensed magnitude of each occurrence of the flowing currents by adding to each sensed magnitude a voltage proportional to the sense voltage. Threshold voltages can be selected by using Zener diodes having different breakdown voltages. Respective ranges within the overall range of the primary supply voltage in which supplemental power limiting occurs and does not occur can thus be controlled.
    Type: Grant
    Filed: May 25, 2007
    Date of Patent: August 28, 2012
    Assignee: Thomson Licensing
    Inventor: William Vincent Fitzgerald
  • Patent number: 8233293
    Abstract: A power supply includes an input, an output, a reverse current protection circuit, a synchronous rectifier and an output choke. The reverse current protection circuit is configured for detecting a flyback voltage indicative of reverse current, and for deactivating the synchronous rectifier in response to detecting the flyback voltage. The flyback voltage can be detected a variety of ways, including across the output choke, across a switch in the synchronous rectifier, across the secondary winding of a power transformer, etc.
    Type: Grant
    Filed: January 18, 2007
    Date of Patent: July 31, 2012
    Assignee: Astec International Limited
    Inventors: Palanivel Selvaraju, Ronnie A. Bagalay
  • Patent number: 8164927
    Abstract: The present invention relates to a switch control device and a switch control method. The present invention controls a switching operation of a power switch that controls output power of a switching mode power supply (SMPS). The present invention generates an operation current corresponding to an input voltage of the SMPS and counts a compensation period in which a power supply voltage generated by the operation current increases from a predetermined counter low-reference voltage to a predetermined counter high-reference voltage. The present invention generates a compensation feedback current depending on the count result, generates a total feedback current by summing a main feedback current having a predetermined value and the compensation feedback current, and generates a power limit current of which a maximum value increases and decreases depending on the total feedback current. Turn-off of the power switch is determined by comparing the current flowing on the power switch with the power limit current.
    Type: Grant
    Filed: December 3, 2009
    Date of Patent: April 24, 2012
    Assignee: Fairchild Korea Semiconductor Ltd.
    Inventors: Sang-Cheol Moon, Young-Bae Park
  • Patent number: 8143875
    Abstract: An example integrated circuit controller for a power supply includes a modulator, a drive signal generator, a comparator, and a variable current limit generator. The modulator generates an enable signal having logic states responsive to a feedback signal. The drive signal generator either enables or skips enabling a switch of the power supply during a switching period in response to the logic state of the enable signal. The comparator asserts an over current signal to disable the switch if current flowing through the switch exceeds a variable current limit. The variable current limit generator sets the variable current limit to a first current limit in response to one logic state of the enable signal during a switching period and sets the variable current limit to a second current limit if the enable signal transitions logic states and the over current signal is asserted during the switching period.
    Type: Grant
    Filed: July 11, 2011
    Date of Patent: March 27, 2012
    Assignee: Power Integrations, Inc.
    Inventors: Alex B. Djenguerian, Stefan Bäurle, Kent Wong
  • Patent number: 8059431
    Abstract: An object of the present invention is to provide a switching power supply which can stably determine whether an overcurrent occurs or not on the secondary side. A sample voltage corresponding to a load current value detected by detection resistors R7 and R8 is compared with a reference voltage by an input-side transistor Q4 and an output-side transistor Q3 which compose a first current mirror circuit 14, so that it is possible to determine whether an overcurrent occurs or not. Moreover, a current passing through the output circuit of the transistor Q3 is temperature-compensated by a second current mirror circuit 17 made up of transistors Q6 and Q5.
    Type: Grant
    Filed: May 19, 2008
    Date of Patent: November 15, 2011
    Assignee: Panasonic Corporation
    Inventors: Hideki Nishihara, Akeyuki Komatsu
  • Patent number: 8036006
    Abstract: A power supply circuit includes a control circuit which outputs a control signal when an in-rush current flows and a power-supply-resistance control circuit which supplies a current to a capacitive load. The power-supply-resistance control circuit, provided in the current path between a power supply and the capacitive load, increases the resistance of the current path in response to the control signal and reduces the resistance of the current path in response to a stop page of the control signal, whereby the control signal is output or stopped so that the in-rush current is suppressed to a value smaller than or equal to a given value.
    Type: Grant
    Filed: December 15, 2008
    Date of Patent: October 11, 2011
    Assignee: Renesas Electronics Corporation
    Inventor: Takashi Tahata
  • Patent number: 8027178
    Abstract: A power conversion apparatus with adjustable leading-edge-blanking (LEB) time and an over current protection (OCP) method thereof are provided. In the OCP method, a pulse-width-modulation (PWM) signal is generated according to the loading status of an electronic device to switch a power switch in the power conversion apparatus and thus the power conversion apparatus to supply an output voltage to the electronic device. A variable or fixed LEB signal is generated according to the PWM signal and the rising and falling edges of a spike signal induced at turn-on instant of the power switch. The PWM signal is constantly/continuously generated to switch the power switch during an enabling period/phase of the variable or fixed LEB signal, and whether an over current is produced in the power conversion apparatus is constantly detected to determine whether to activate an OCP mechanism during a disabling period/phase of the variable or fixed LEB signal.
    Type: Grant
    Filed: July 30, 2010
    Date of Patent: September 27, 2011
    Assignee: Power Forest Technology Corporation
    Inventor: Ju-Lin Chia
  • Patent number: 8018745
    Abstract: System and method for protecting a power converter. A system includes a threshold generator configured to generate a threshold signal, and a first comparator configured to receive the threshold signal and a first signal and to generate a comparison signal. The first signal is associated with an input current for a power converter. Additionally, the system includes a pulse-width-modulation generator configured to receive the comparison signal and generate a modulation signal in response to the comparison signal, and a switch configured to receive the modulation signal and adjust the input current for the power converter. The threshold signal is associated with a threshold magnitude as a function of time. The threshold magnitude increases with time at a first slope during a first period, and the threshold magnitude increases with time at a second slope during a second period. The first slope and the second slope are different.
    Type: Grant
    Filed: January 20, 2010
    Date of Patent: September 13, 2011
    Assignee: On-Bright Electronics (Shanghai) Co., Ltd.
    Inventors: Lieyi Fang, Shifeng Zhao, Bo Li, Zhiliang Chen
  • Patent number: 8009449
    Abstract: Embodiments of the invention relate generally to semiconductors for power generation and conversion applications, and more particularly, to devices, integrated circuits, substrates, and methods to convert direct current (“DC”) voltage signals to alternating current (“AC”) voltage signals. In some embodiments, an inverter can include a modulator configured to convert a direct current signal into a first variable signal, and a transformation module configured to step up the first variable signal to form a second variable signal. The transformation module can be configured to generate a first portion of the second variable signal and a second portion of the second variable signal. Further, the inverter can include a waveform generator configured to synchronize the first portion and the second portion of the second variable signal at a frequency to generate an alternating current (“AC”) signal.
    Type: Grant
    Filed: June 5, 2009
    Date of Patent: August 30, 2011
    Assignee: NPhysics, Inc
    Inventors: Dalun Yuan, Tranh Nguyen
  • Patent number: 7990125
    Abstract: Techniques are disclosed to adjust a current limit in a switching regulator. One example switching regulator includes a comparator having first and second inputs and an output. The first input of the comparator is adapted to sense a current flow through a switch and the second input of the comparator is adapted to sense a variable current limit value. A controller is coupled to the output of the comparator and to the switch to control switching of the switch to regulate an output of a power supply in response a feedback signal. The controller disables the switch if the sensed current flow through the switch is greater than the sensed variable current limit value. The variable current limit value is set to a first variable current limit value by the controller in response to an input line voltage of the power supply if there is not an over current condition during a first switching cycle that occurs after a skipped switching cycle of the switch.
    Type: Grant
    Filed: June 19, 2009
    Date of Patent: August 2, 2011
    Assignee: Power Integrations, Inc.
    Inventors: Alex B. Djenguerian, Stefan Bäurle, Kent Wong
  • Publication number: 20110182092
    Abstract: An inverter has a current sensor that senses a low side current before a high side of the inverter is permitted to power up. If an over-current situation is detected on the low side, powering up is prevented in order to avoid damage to the rectifier.
    Type: Application
    Filed: July 4, 2008
    Publication date: July 28, 2011
    Inventor: Richard Kenney
  • Patent number: 7986537
    Abstract: A DC-to-DC converter having an active switch connected between a pair of DC input terminals via the primary winding of a transformer whose secondary winding is connected to a pair of DC output terminals via a rectifying and smoothing circuit. Operating under the control of an output voltage detector circuit, a switch control signal generator rapidly turns the active switch on and off so as to keep the DC output voltage constant. For overcurrent protection, a current detect resistor is connected in series with the active switch for providing an uncorrected current detect signal indicative of the current flowing through the active switch. An overcurrent protector generates, in response to a clocked ramp voltage, a correction voltage which builds up with time during each conducting period of the active switch. The correction voltage is subtracted from the uncorrected current detect signal to provide a corrected current detect signal.
    Type: Grant
    Filed: October 16, 2008
    Date of Patent: July 26, 2011
    Assignee: Sanken Electric Co., Ltd.
    Inventor: Masaru Nakamura
  • Patent number: 7961485
    Abstract: In one embodiment, a PWM controller is configured to inhibit forming a drive signal responsively to an overload sense signal having a value that is no greater than a first value for a first time interval and to form a first duration of the first time interval responsively to the overload sense signal.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: June 14, 2011
    Assignee: Semiconductor Components Industries, LLC
    Inventor: Jonathan P. Kraft
  • Publication number: 20110075452
    Abstract: A detecting device detects the midpoint voltage of a half bridge circuit of transistors. The circuit comprises a bootstrap capacitor having one terminal connected to the midpoint node of the half bridge circuit and another terminal connected to a supply circuit. The device comprises a further capacitor connected between a second terminal of the bootstrap capacitor and circuit means adapted to form a low impedance node for a current signal circulating in said further capacitor during the transitions from the low value to the high value and from the high value to the low value of the midpoint voltage. The device comprises a detector to detect said current signal circulating in said further capacitor and to output at least a first signal indicating the transitions from the low value to the high value or from the high value to the low value according to said current signal.
    Type: Application
    Filed: September 28, 2010
    Publication date: March 31, 2011
    Applicant: STMICROELECTRONICS S.R.L.
    Inventors: Christian Leone Santoro, Aldo Vittorio Novelli, Claudio Adragna
  • Patent number: 7884557
    Abstract: A light source is protected by selectively coupling a shunt path in parallel with the light source, such that current is diverted away from the light source and through the shunt path. A detection circuit detects the current flowing in the shunt path when the shunt path is connected in parallel with the light source. A comparator determines whether the current flowing in the shunt path exceeds a predetermined threshold and, if so, prevents or limits the flow of current when the shunt path is disconnected from being in parallel with the light source. In this way, a current detector is provided for monitoring the flow of current in a shunt path, the current detector being configured to disable or limit the flow of current through a light source when a predetermined threshold is reached.
    Type: Grant
    Filed: July 10, 2007
    Date of Patent: February 8, 2011
    Assignee: Wolfson Microelectronics plc
    Inventors: Colin Steele, Catherine A. Hearne, David P. Singleton
  • Patent number: 7872881
    Abstract: In one embodiment, a power supply includes a flyback transformer having a primary winding and at least two secondary windings. An output voltage is developed across a first one of the secondary windings. The power supply includes a transistor coupled to the first one of the secondary windings. The output voltage is regulated about a nominal output voltage by operating the transistor in a linear mode when current is flowing through the first one of the secondary windings and by operating the transistor in an off mode when current is not flowing through the first one of the secondary windings.
    Type: Grant
    Filed: August 17, 2005
    Date of Patent: January 18, 2011
    Assignee: ADC DSL Systems, Inc.
    Inventor: Randall L. Powers
  • Patent number: 7855540
    Abstract: A high voltage power supply method and apparatus is disclosed. An example power supply circuit includes a rectifier circuit coupled to receive an AC input voltage. A switchmode power converter circuit is coupled to the rectifier circuit to receive a rectified input voltage to generate a regulated output voltage. A switch is coupled between the rectifier circuit and the switchmode power converter circuit. A sense circuit is coupled to detect the AC input voltage. The sense circuit is coupled to turn off the switch when an absolute value of the AC input voltage exceeds a first threshold value. The sense circuit is coupled to turn on the switch when the absolute value of the AC input voltage is below a second threshold value.
    Type: Grant
    Filed: December 31, 2008
    Date of Patent: December 21, 2010
    Assignee: Power Integrations, Inc.
    Inventor: David Michael Hugh Matthews
  • Patent number: 7848124
    Abstract: A converter and a driving method thereof are provided. The converter can determine the output short state of the converter after the soft start is finished by using a detection signal that corresponds to an input signal while a switched is turned on and that corresponds to an output signal while the switch is turned off, so as to convert the input signal into the output signal according to a switching operation of the switch. The converter can determine the overload state of the converter by using a feedback voltage corresponding to the output signal, and terminate the switching operation when the converter is in an output short state or overload state.
    Type: Grant
    Filed: March 25, 2008
    Date of Patent: December 7, 2010
    Assignee: Fairchild Korea Semiconductor, Ltd.
    Inventors: Hang-Seok Choi, Young-Bae Park, Gwan-Bon Koo, Jin-Tae Kim
  • Patent number: 7821800
    Abstract: Disclosed is a power adapter having a voltage limiting circuit for limiting an output voltage of the power adapter at a predetermined voltage level when an output current of the power adapter is smaller than a threshold current, and a power limiting circuit for limiting an output power of the power adapter at a predetermined power level when an output current of the power adapter reaches the threshold current, in which the voltage limiting circuit can be configured to receive a current control signal from a load and in response thereto issue a load current regulation signal to a switching control circuit of the power adapter, thereby regulating the output voltage of the power adapter based on the load current regulation signal.
    Type: Grant
    Filed: July 3, 2007
    Date of Patent: October 26, 2010
    Assignee: Delta Electronics, Inc.
    Inventor: Chin-Tsai Chiang
  • Patent number: 7800927
    Abstract: A method and circuit for providing compensation of a power converter is proposed. A current sense circuit is coupled to receive a switching current for generating a current signal. A signal generation circuit is developed to generate a first compensation signal and a second compensation signal for adjusting the current signal. The first compensation signal is coupled to adjust the current signal for the output power limit of the power converter. The second compensation signal is coupled to adjust the current signal for the slope compensation. The slope of the first compensation signal is decreased when the power transistor is turned on. The slope of the second compensation signal is increased in response to the turn on of the power transistor.
    Type: Grant
    Filed: December 14, 2006
    Date of Patent: September 21, 2010
    Assignee: System General Corp.
    Inventor: Ta-yung Yang
  • Patent number: 7772824
    Abstract: A control method for adjusting leading edge blanking time in a power converting system is disclosed. The control method includes: receiving a feedback signal relative to a load connected to an output terminal of the power converting system; determining the leading edge blanking time to be a first value if the feedback signal has a magnitude about a first voltage; and determining the leading edge blanking time to be a second value if the feedback signal has a magnitude about a second voltage, wherein the first value is smaller than the second value, and the first voltage is greater than the second voltage.
    Type: Grant
    Filed: October 6, 2009
    Date of Patent: August 10, 2010
    Assignee: Leadtrend Technology Corp.
    Inventors: Yuan-Wen Chang, Yu-Bin Wang, Ming-Nan Chuang, Yu-Chuan Liu
  • Patent number: 7759922
    Abstract: Various techniques directed to providing temporary peak power from a switching regulator are disclosed. In one aspect, a switching regulator includes a switch that is to be coupled between a power supply input and an energy transfer element of the power supply. A controller is coupled to be responsive to a feedback signal to be received from an output of the power supply. The controller is coupled to switch the switch in response to the feedback signal to regulate the output of the power supply. An oscillator is coupled to provide an oscillating signal to the controller to determine a maximum switching frequency of the switch. The oscillating signal is coupled to oscillate at a first frequency under a first moderate load condition at the power supply output. The oscillating signal is coupled to oscillate at a second frequency under a second peak load condition at the power supply output.
    Type: Grant
    Filed: April 27, 2009
    Date of Patent: July 20, 2010
    Assignee: Power Integrations, Inc.
    Inventors: Stefan Bäurle, William M. Polivka, David Michael Hugh Matthews
  • Patent number: RE42674
    Abstract: The present invention provides a method and a control circuit to detect an input voltage for the control and protections of a power converter. It includes a current sense circuit for generating a current signal in response to a switching current of a transformer. A detection circuit is coupled to sense the current signal for generating a slope signal in response to a slope of the current signal. A protection circuit is further developed to control the switching signal in accordance with the slope signal. The level of the slope signal is corrected correlated to the input voltage of the power converter.
    Type: Grant
    Filed: August 4, 2010
    Date of Patent: September 6, 2011
    Assignee: System General Corp.
    Inventors: Ta-Yung Yang, Chien-Yuan Lin