With Reference Voltage Circuitry Patents (Class 323/281)
  • Publication number: 20110317729
    Abstract: A current driving device comprises; a three-terminal regulator configuration circuit operative as a three-terminal regulator which drops a voltage of a first electric power supply to a predetermined target output voltage in a state where a main terminal and a control terminal of a power transistor are connected to a main terminal connection terminal and a control terminal connection terminal, respectively; a voltage setting circuit which sets a control voltage corresponding to a target output voltage which is applied from the three-terminal regulator configuration circuit to the control terminal of the power transistor; and a voltage restricting circuit which is connected to the control terminal connection terminal and controls the control voltage applied to the control terminal of the power transistor so that the output voltage of the three-terminal regulator configuration circuit becomes a predetermined voltage or less, upon being supplied with the electric power from the first electric power supply.
    Type: Application
    Filed: June 23, 2011
    Publication date: December 29, 2011
    Inventors: Takeshi MATSUMOTO, Kenichi Tatehara, Toshiyuki Shimada, Yuichi Takahashi
  • Patent number: 8085019
    Abstract: Example embodiments relate to an internal power supply voltage generating device. The internal power supply voltage generating device may include a start-up voltage generating part, a reference voltage generating part, and/or an internal power supply voltage generating part. The start-up voltage generating part may be configured to generate a start-up voltage using an external power supply voltage. The reference voltage generating part may be configured to generate a reference voltage using the start-up voltage. The internal power supply voltage generating part may be configured to generate an internal power supply voltage using the reference voltage and the external power supply voltage. The start-up voltage generating part may be turned off by the reference voltage generated by the reference voltage generating part. Example embodiments also relate to a method of generating an internal power supply voltage.
    Type: Grant
    Filed: October 19, 2007
    Date of Patent: December 27, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jong-Pil Cho, Chan-Yong Kim
  • Publication number: 20110298432
    Abstract: Apparatus and methods for providing variable regulated voltages are disclosed. Variable voltage control elements can adjust a regulated voltage provided by a single voltage regulator, thereby providing a variable regulated voltage. The regulated voltage can be used in a variety of applications, for example, as a bias voltage for a power amplifier.
    Type: Application
    Filed: July 27, 2010
    Publication date: December 8, 2011
    Applicant: Skyworks Solutions, Inc
    Inventors: Karl J. Couglar, Ryan M. Pratt
  • Patent number: 8072329
    Abstract: The present disclosure provides examples of a voltage regulator for a Radio Frequency Identification tag circuit. The voltage regulator includes a pair of native transistors. A first native transistor is coupled to a reference voltage and biased to saturation. A resistive element coupled between the gate and the drain of the transistor ensures a sufficient voltage difference between the source and the drain of the first native transistor. The second native transistor, with a gate coupled to the gate of the first native transistor, outputs a regulated voltage.
    Type: Grant
    Filed: December 2, 2008
    Date of Patent: December 6, 2011
    Assignee: Impinj, Inc.
    Inventors: Shailendra Srinivas, Jay A. Kuhn
  • Patent number: 8040118
    Abstract: A low-dropout (LDO) voltage regulator that includes an error amplifier which compares a reference voltage with a feedback voltage of an output voltage and outputs an error signal based on the result of the comparison, the error amplifier being biased by an input voltage; a first MOS transistor having a gate electrically connected to the error signal, a source electrically connected to the input voltage and a drain electrically connected to the output voltage; a voltage divider which transmits a predetermined part of the output voltage to the error amplifier as feedback voltage; and a level limiter which limits a level of the output voltage from changing beyond and below an offset voltage when a level of a load current changes. In accordance with embodiments, A predetermined number of comparators and MOS transistor type-switches are provided to enhance the slew ratio of the regulated output voltage and to reduce standby electricity consumption.
    Type: Grant
    Filed: December 10, 2009
    Date of Patent: October 18, 2011
    Assignee: Dongbu HiTek Co., Ltd.
    Inventors: Sung-Il Cho, Sung-Man (Chang woo) Pang (Ha)
  • Publication number: 20110234186
    Abstract: A high voltage power supply is provided. The high voltage power supply includes a soft-start circuit unit which outputs a natural voltage that decreases exponentially as time elapses and converts the natural voltage into a forced voltage having a predetermined scale if an enable signal is applied, a controller which compares the natural voltage output from the soft-start circuit unit with a reference voltage and outputs a control signal, and a converting unit which delays outputting a final voltage during a first predetermined time period and outputs the final voltage, which gradually increases as time elapses according to the control signal.
    Type: Application
    Filed: November 22, 2010
    Publication date: September 29, 2011
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Pankaj AGARWAL, Joon-hyun YANG, Sung-jin CHOI
  • Patent number: 8008889
    Abstract: A charging circuit charges a secondary battery by using a first direct current power supply that generates and outputs a first voltage. A highest voltage among the first voltage of the first direct current power supply, a second voltage generated from power supplied from outside, and a secondary battery voltage of the secondary battery is supplied as a power supply to the charging circuit.
    Type: Grant
    Filed: February 2, 2007
    Date of Patent: August 30, 2011
    Assignee: Ricoh Company, Ltd.
    Inventor: Ippei Noda
  • Patent number: 7994764
    Abstract: A low dropout voltage regulator includes an error amplifier, a voltage divider, and a voltage reference/amplifier circuit. The error amplifier has first and second input terminals, a power supply terminal for receiving an input voltage, and an output terminal for providing a regulated output voltage. The voltage divider provides a feedback voltage as a predetermined fraction of said regulated output voltage. The voltage reference/amplifier circuit provides a first voltage to said first input terminal of said error amplifier that varies inversely with variations of said feedback voltage, and provides a second voltage to said second input terminal of said error amplifier that varies by substantially the same amount over temperature as variations in said first voltage.
    Type: Grant
    Filed: November 11, 2008
    Date of Patent: August 9, 2011
    Assignee: Semiconductor Components Industries, LLC
    Inventor: Rastislav Koleno
  • Patent number: 7960955
    Abstract: A linear regulator is provided which stabilizes an input voltage based on a reference voltage source that generates a reference voltage, and the reference voltage generated by the reference voltage. An output voltage of the linear regulator is supplied as a power supply voltage of a switching controller and the reference voltage source. The linear regulator is configured to enable switching of a regulation mode in which voltage is outputted according to the reference voltage, and a bypass mode in which an input voltage is outputted as it is, with no relation to the reference voltage. When a power supply apparatus is started up, during a time period until the input voltage reaches a predetermined threshold voltage, the linear regulator operates in the bypass mode, and when the input voltage exceeds the threshold voltage, operates in the regulation mode.
    Type: Grant
    Filed: November 30, 2006
    Date of Patent: June 14, 2011
    Assignee: Rohm Co., Ltd.
    Inventors: Tomoyuki Ito, Yoichi Tamegai, Koki Tamakawa, Isao Yamamoto
  • Publication number: 20110121802
    Abstract: A low dropout regulator (LDO) circuit without external capacitors rapidly responding to load change includes a slow pathway and a fast pathway for controlling voltage, wherein the slow pathway for providing precise output voltage includes an operational amplifier I0, a driving transistor MPR, a resistor RF1 and a resistor RF2 forming an operational amplifier loop, and the fast pathway for responding to rapid load change includes a comparator I1, a comparator I2, a field effect transistor MN1, a field effect transistor MN2, a driving transistor MPR, a resistor RF1 and a resistor RF2 forming a comparator loop. The circuit is capable of controlling the output voltage by the slow operational amplifier loop and fast comparator loop, so that the load response speed of the LDO is greatly improved without the increase of the system power consumption and external big capacitors.
    Type: Application
    Filed: June 4, 2010
    Publication date: May 26, 2011
    Inventor: Guojun Zhu
  • Patent number: 7948223
    Abstract: A constant voltage circuit that is capable of realizing high speed response with respect to an abrupt change in an input voltage or a load current is disclosed. The constant voltage circuit includes a first error amplifier with a high direct current gain and a second error amplifier with high speed responsiveness with respect to a change in an output voltage. The constant voltage circuit uses the first and second error amplifiers to conduct operation control of an output voltage control transistor in response to a change in the output voltage.
    Type: Grant
    Filed: March 27, 2008
    Date of Patent: May 24, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Toshihisa Nagata, Kohji Yoshii, Yusuke Minakuchi
  • Publication number: 20110095737
    Abstract: A voltage regulator and an integrated circuit using the voltage regulator is provided. The voltage regulator has a bandgap reference circuit, an operational amplifier, a power transistor and a voltage divider. The bandgap reference circuit generates a bandgap reference voltage. The operational amplifier receives the bandgap reference voltage and a feedback voltage to output a control signal for the power transistor. The power transistor is powered by a first voltage source and transforms the first voltage source to a second voltage source according to the control signal. The second voltage source is divided by the voltage divider to generate the feedback voltage and is further used in powering the bandgap reference circuit and the operational amplifier.
    Type: Application
    Filed: October 27, 2009
    Publication date: April 28, 2011
    Applicants: HIMAX TECHNOLOGIES LIMITED, HIMAX MEDIA SOLUTIONS, INC.
    Inventors: Yuan-Kai Chu, Hui-Min Wang
  • Patent number: 7928711
    Abstract: A linear voltage regulator is provided which has a pair of complementary power transistors connected “back to back” in series between a voltage input and a voltage output. A current sense circuit including a current sense resistor is connected in parallel across one of the power transistors, such as the one connected to the voltage input. As long as the voltage drop in the current sense circuit remains small, i.e. less than app. 0.7V, the current flowing through the bulk diode of the power transistor remains negligible and the entire output current flows through the current sense circuit. For higher output currents the voltage drop across the current sense circuit is limited by the parallel bulk diode of the power transistor. The current sense resistor can be dimensioned to generate a relatively high voltage drop of e.g. 100 mV, and a high accuracy of open load detection is achieved without the requirement for a high precision comparator.
    Type: Grant
    Filed: March 17, 2009
    Date of Patent: April 19, 2011
    Assignee: Texas Instruments Deutschland GmbH
    Inventor: Marcin K. Augustyniak
  • Patent number: 7923980
    Abstract: In a digital controlled power supply including a digital controller for generating a PWM signal which is used to turn on and off a switching element to obtain an output voltage for a load based on an input voltage, the digital controller includes an AD converter for receiving an analog output current from the power supply and converting the current into a digital value to produce a digital output current value, an arithmetic processing unit for conducting an arithmetic operation of a pulse width for each period of a sampling frequency of the AD converter or a frequency of carrier wave as a criterion to obtain the PWM signal, and a frequency controller for variably controlling the frequency of carrier wave and the sampling frequency on the basis of the digital output current value from the AD converter.
    Type: Grant
    Filed: October 16, 2008
    Date of Patent: April 12, 2011
    Assignee: Hitachi Computer Peripherals Co., Ltd.
    Inventors: Fumikazu Takahashi, Masahiro Hamaogi
  • Patent number: 7893672
    Abstract: An electronic device includes a low drop-out regulator for providing a regulated output voltage. The low drop-out regulator generally comprises a power MOSFET transistor having a gate coupled to a driver. The driver has a first path including an NMOS transistor and being coupled to the gate of the power MOSFET, a second path having a PMOS transistor and being coupled to the gate of the power MOSFET, and a switch for alternately switching between the first and second paths so as to provide a voltage to the gate of the power MOSFET ranging from ground to a power supply level.
    Type: Grant
    Filed: March 4, 2009
    Date of Patent: February 22, 2011
    Assignee: Texas Instruments Deutschland GmbH
    Inventors: Kevin Scoones, Anmol Sharma
  • Patent number: 7884589
    Abstract: A controllable power supply device with a step-up function including a constant voltage generator, a programmable voltage generator, a first switch and a linear regulator is provided. The constant voltage generator is used to provide an initial voltage. The programmable voltage generator is used to receive the initial voltage and adjust the received initial voltage to boost the initial voltage to a power supply voltage. The first connecting terminal of the first switch is used to receive the initial voltage, the second connecting terminal of the first switch is used to receive the power supply voltage, and the third connecting terminal of the first switch is coupled to one of the first connecting terminal and the second connecting terminal. Therefore, the voltage from the third connecting terminal of the first switch is stabilized and is outputted as the output voltage of the controllable power supply device by the linear regulator.
    Type: Grant
    Filed: April 13, 2008
    Date of Patent: February 8, 2011
    Assignee: ASUSTeK Computer Inc.
    Inventor: Yung-Lun Lin
  • Patent number: 7882383
    Abstract: A system on a chip includes a real time clock (RTC) module, a crystal oscillation circuit and a voltage supply circuit. The RTC module is coupled to provide timing functions and the crystal oscillation circuit is coupled to produce an oscillation. The voltage supply circuit is coupled to produce a supply voltage for at least a portion of the RTC module and the crystal oscillation circuit. The voltage supply circuit includes: a reference circuit coupled to produce a reference voltage based on the supply voltage; a transistor coupled to the battery IC pin, wherein the transistor produces the supply voltage based on a regulation signal and the battery voltage; an amplifier coupled to produce the regulation signal based on the reference voltage and a feedback representation of the supply voltage; and a start-up circuit coupled to enable the voltage supply circuit at battery connection.
    Type: Grant
    Filed: April 25, 2007
    Date of Patent: February 1, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Marcus W. May, David A. Dyches
  • Patent number: 7863876
    Abstract: A reference voltage regulation circuit (143) is provided in which one or more input voltage signals (Vref, Vref?) are selectively coupled to a configurable amplifier (114) which is coupled through a sample and hold circuit (120) to a voltage follower circuit (122) which is coupled in feedback to the configurable amplifier (114) for generating an adjusted output voltage at a circuit output (130), where the voltage follow circuit comprises a resistor divider circuit (126) that is controlled by a calibration signal (Cal<n:0>) generated by a counter circuit (128) selectively coupled to the output of the configurable amplifier when configured as a comparator for generating the calibration signal in response to a clock signal, where the calibration signal represents a voltage error component (Verror, Voffset) that is removed from the circuit output when the calibration signal is applied to the resistor divider circuit during normal operational.
    Type: Grant
    Filed: March 26, 2008
    Date of Patent: January 4, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Thomas D. Cook, Tahmina Akhter, Jeffrey C. Cunningham
  • Patent number: 7855542
    Abstract: A voltage regulator circuit comprises an amplifier, bias network and startup circuit. The bias network is configured to generate a bias voltage for setting a bias current in the amplifier. The startup circuit is configured to mirror the amplifier bias current and to assist the bias network in setting the amplifier bias current based on the mirrored amplifier bias current until the bias voltage approximates a desired level.
    Type: Grant
    Filed: July 17, 2007
    Date of Patent: December 21, 2010
    Assignee: Qimonda AG
    Inventor: Benjamin Heilmann
  • Patent number: 7855537
    Abstract: A voltage supply circuit includes an output transistor causing a first current to flow to an output terminal of the voltage supply circuit based on a control voltage applied from an error amplifier to a control terminal of the output transistor; and an overcurrent protection circuit including a reference transistor causing a second current to flow to the output terminal, the second current having an amount corresponding to an amount of the first current, the overcurrent protection circuit regulating a level of the control voltage based on comparison between a detection voltage caused based on the second current and a reference voltage.
    Type: Grant
    Filed: November 6, 2007
    Date of Patent: December 21, 2010
    Assignee: NEC Electronics Corporation
    Inventor: Hiroki Aizawa
  • Patent number: 7855536
    Abstract: Source voltage and substrate voltage are supplied to a semiconductor integrated circuit 1E from the regulator circuits 11C and 21C of a power supply circuit 1C via a power detection compensating circuit 1D. The power efficiency value of a regulator is stored in the resistor file 13D, various detection information and power values are input to an operator 14D, the power values and the power efficiency values of the regulator circuits 11C and 21C are accumulated, and the power sum of a semiconductor integrated circuit 1E and a power supply circuit 1C are output. Minimum power implementation information corresponding to the various detection information of the semiconductor integrated circuit 1E is stored in an LUT 15D. Variable resistances R1a and R2a are controlled for determining the reference voltage values of the regulator circuits 11C and 21C so that the power sum is the minimum power value by comparing the minimum power implementation information with the output 14D.
    Type: Grant
    Filed: December 28, 2006
    Date of Patent: December 21, 2010
    Assignee: Panasonic Corporation
    Inventor: Masaya Sumita
  • Patent number: 7853810
    Abstract: A core voltage controlling apparatus suitable for a center processing unit (CPU) is provided. The apparatus includes a level shifting unit, a time-delay unit and a logic unit. An input terminal of the level shifting unit receives and shifts a first voltage signal, and an output terminal generates a second voltage signal, in which the first voltage signal indicates a power-on stable state, and the second voltage signal indicates a magnitude of the core voltage. The time-delay unit delays the second voltage signal to generate a third voltage signal. The logic unit is coupled to the time-delay unit for performing a logic operation on the third voltage and a fourth voltage signal transmitted by a power supply, and generating a fifth voltage signal for controlling a core voltage generator whether to provide the core voltage to the CPU or not, in which the fourth voltage signal indicates a power state.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: December 14, 2010
    Assignee: Inventec Corporation
    Inventors: Lan Huang, Shih-Hao Liu
  • Patent number: 7852062
    Abstract: A reference current generating apparatus is provided which is capable of generating a reference current having no temperature dependency, without increasing a layout area. The reference current generating apparatus includes a constant current generating circuit having a differential amplifier, a constant current generating circuit connected to the constant current generating circuit and having a differential amplifier, and an output circuit connected to the constant current generating circuit for outputting first and second reference voltages. The constant current generating circuit generates a reference current by enabling selection of a mirror ratio of a transistor that conducts summing of a constant current proportional to a thermal voltage, and by enabling switching of a dividing voltage from a resistor to an input of the differential amplifier, to generate a constant current proportional to a diode voltage via a high impedance MOS gate.
    Type: Grant
    Filed: June 9, 2008
    Date of Patent: December 14, 2010
    Assignee: Oki Semiconductor Co., Ltd.
    Inventor: Naoaki Sugimura
  • Publication number: 20100289465
    Abstract: Systems and methods providing for improved voltage regulation of a supply voltage for an integrated circuit are described herein. The voltage regulator circuit includes a feedback circuit coupled to a first current path and adapted to maintain a gate voltage of a feedback transistor substantially constant. A pass device is coupled to a second current path and adapted to receive a signal with a magnitude based on first and second currents supplied by first and second current sources to the second current path. In an embodiment, the first current is a substantially constant current and the second current has a magnitude based on a magnitude of the voltage at the feedback transistor gate and a magnitude of a voltage at an output of the voltage regulator circuit coupled to the pass device.
    Type: Application
    Filed: May 12, 2009
    Publication date: November 18, 2010
    Applicant: SANDISK CORPORATION
    Inventor: Tomer Shaul Elran
  • Patent number: 7830129
    Abstract: A control circuit, applicable to a voltage regulator including a power switch. The control circuit includes a variable resistance generating unit and a detecting circuit. The variable resistance generating unit provides a variable resistor with resistance that varies over time. A reference current representing the current flowing through the power switch flows through the resistor to generate a first feedback voltage. The detecting circuit reduces the conduction of the power switch when the first feedback voltage is detected as being equal to or exceeding a predetermined voltage level.
    Type: Grant
    Filed: November 13, 2008
    Date of Patent: November 9, 2010
    Assignee: Leadtrend Technology Corp.
    Inventor: Yang-Tai Tseng
  • Publication number: 20100253297
    Abstract: A soft-start circuit is provided. The soft-start circuit comprises: an input stage, a pump stage, a second resistor and a capacitor. The input stage comprises a first resistor to receive an input voltage to provide a reference current at a first node. The pump stage comprises N current branches connected in parallel each comprising a current source connected to the first node and a switch to transfer the current from the current source to the second node while the switch operates in a connecting state. The switches has 2N connecting modes performed one after another to generate an output current with a gradual increment output current at the second node with 2N current levels; and the second resistor and the capacitor are connected in parallel between the second node and the ground potential to generate an output voltage with a gradual increment with 2N voltage levels according to output current.
    Type: Application
    Filed: April 7, 2009
    Publication date: October 7, 2010
    Applicant: HIMAX ANALOGIC, INC.
    Inventor: Jyi-Hung Tseng
  • Patent number: 7804284
    Abstract: The invention relates to a regulator with a reference generator circuit (e.g., a band-gap reference) and a reference generator power selector. The reference generator power selector selectively powers the reference generator circuit from an input power signal during start-up and from a regulated power signal during steady-state operation. The reference generator power selector may also select from multiple regulated power signals during steady-state operation.
    Type: Grant
    Filed: October 12, 2007
    Date of Patent: September 28, 2010
    Assignee: National Semiconductor Corporation
    Inventor: Kern Wai Wong
  • Publication number: 20100213908
    Abstract: Low dropout regulators capable of preventing damage caused by a short circuit or a heavy load are provided, in which a pass transistor receives an unregulated power supply voltage to generate a regulated output voltage according to a control signal. Additionally, a constant overcurrent limiting circuit limits an output current through the pass transistor to below a predetermined current, and a foldback overcurrent limiting circuit enables the constant overcurrent limiting circuit to further decrease the output current, when the regulated output voltage is lower than a predetermined voltage.
    Type: Application
    Filed: February 25, 2009
    Publication date: August 26, 2010
    Applicant: MEDIATEK INC.
    Inventor: Tun-Shih Chen
  • Patent number: 7782034
    Abstract: A constant-voltage power supply circuit is disclosed that is able to prevent overshoot of an output voltage possibly occurring when changing a constant-voltage circuit in operation and is able to supply a constant output voltage. The constant-voltage power supply circuit includes a first constant-voltage circuit, having a first output transistor and a first output voltage controller, that generates a first reference voltage and generates a first proportional voltage in proportion to a voltage on an output terminal, and a second constant-voltage circuit having a second output transistor and a second output voltage controller that generates a second reference voltage and generates a second proportional voltage in proportion to the voltage on the output terminal.
    Type: Grant
    Filed: July 11, 2008
    Date of Patent: August 24, 2010
    Assignee: Ricoh Company, Ltd.
    Inventor: Shunsei Tanaka
  • Patent number: 7768214
    Abstract: A step-up/step-down regulator circuit wherein a switch has a terminal connected to an end of an inductor, another terminal grounded, and a control terminal connected to an end of a switch. In this way, performing an open/close control of the switch can indirectly perform an open/close control of the switch, thereby solving the problem that the structure and operation of a switch control circuit will be complicated when the switching between step-up and step-down operation is realized.
    Type: Grant
    Filed: October 21, 2005
    Date of Patent: August 3, 2010
    Assignee: Rohm Co., Ltd.
    Inventors: Mikiya Doi, Kenichi Nakata
  • Publication number: 20100164445
    Abstract: A digital linear voltage regulator includes a comparator, a finite state machine, and a current digital-to-analog converter (DAC). The comparator is preferably coupled to receive a reference voltage and an operating voltage supplied to a dynamic load. The comparator generates, during a clock cycle, a binary output based on a comparison between reference and operating voltages. The finite state machine (FSM) is coupled to receive at least one control signal that indicates a target operating state for the digital linear voltage regulator. The FSM receives the binary output from the comparator and generates a digital word, during a clock cycle, based on the target operating state of the digital linear voltage regulator and on the binary output. The current DAC is coupled to the FSM, receives the digital word and delivers current at the desired voltage to the dynamic load.
    Type: Application
    Filed: March 12, 2010
    Publication date: July 1, 2010
    Inventors: Shwetabh Verma, Marc Loinaz
  • Patent number: 7728566
    Abstract: A voltage regulator having a MOS transistor driver includes a p-channel MOS transistor at a voltage input terminal Vin and a p-channel MOS transistor at a voltage output terminal Vout. A drain of the input side p-channel MOS transistor is connected to the voltage input terminal Vin. A threshold voltage or a voltage lower than the threshold voltage is applied to a gate of the input side p-channel MOS transistor. A drain of the output side p-channel MOS transistor is connected to the voltage output terminal Vout. A current flowing through the input side p-channel MOS transistor drives a voltage regulator circuit and the output side p-channel MOS transistor.
    Type: Grant
    Filed: May 27, 2008
    Date of Patent: June 1, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Takaaki Negoro, Koichi Morino
  • Patent number: 7719243
    Abstract: In one embodiment, a method for soft-start in a power converter includes the following: providing a feedback signal indicative of the output voltage of the power system at a first input terminal of an error amplifier in a negative feedback loop of the power converter; providing a reference voltage at a second input terminal of the error amplifier; comparing the feedback signal against the reference voltage to generate a control signal for regulating an output voltage of the power converter; charging a soft-start capacitor coupled to the second input terminal of the error amplifier with a current for establishing the reference voltage; and adjusting the current in response to the control signal so that the error amplifier is prevented from saturation.
    Type: Grant
    Filed: November 21, 2007
    Date of Patent: May 18, 2010
    Assignee: Fairchild Semiconductor Corporation
    Inventor: Laszlo Balogh
  • Patent number: 7705575
    Abstract: A standby regulator circuit includes a standby bias circuit and a standby operational amplifier. The standby regulator circuit provides a standby regulated control voltage to a multiplexer. A regular operational amplifier provides a regulated control voltage to the multiplexer. During regular operation, the multiplexer selects the regular operational amplifier and selects the standby regulator circuit in a low-power mode. The multiplexer couples to a native pass transistor gate having a threshold voltage about equal to 0 V. The native pass transistor provides a regulated output voltage with relatively low-level input control voltages. In low-power mode, a power-down signal, provided to the multiplexer, smoothly transitions regulated control voltage from the regular operational amplifier to regulated control voltage sourcing from the standby operational amplifier.
    Type: Grant
    Filed: April 10, 2009
    Date of Patent: April 27, 2010
    Assignee: SpectraLinear, Inc.
    Inventors: Ahmet Akyildiz, Alexei Shkidt
  • Publication number: 20100090666
    Abstract: According to the method for regulating the supply voltage Uo of an electronic circuit a regulating element with variable resistivity and the outer supply voltage Ui being applied to an input terminal of said regulating element is controlled by an amplified difference between a reference voltage and a part of a regulated supply voltage Uo, whereat at first an instant, on which the regulating circuit and the electronic circuit start operating, is detected, and then such value of the reference voltage is set on said instant that the regulated supply voltage Uo will equal a maximum allowable supply voltage of the electronic circuit and the supplied electronic circuit puts itself in a state of a maximum current consumption.
    Type: Application
    Filed: March 19, 2008
    Publication date: April 15, 2010
    Inventors: Vinko Kunc, Maja Atanasijevic-Kunc, Andrej Vodopivec
  • Publication number: 20100085024
    Abstract: An embodiment of a power-supply controller includes a control circuit and a detection circuit. The control circuit has a signal characteristic, and is operable in response to a regulated output signal and a reference signal to cause at least one power-supply phase to generate the regulated output signal. The detection circuit is operable to detect a change in the regulated output signal, and to alter the signal characteristic of the control circuit in response to the detected change.
    Type: Application
    Filed: July 6, 2009
    Publication date: April 8, 2010
    Applicant: INTERSIL AMERICAS INC.
    Inventors: Michael Jason Houston, Shawn Evans
  • Publication number: 20100072961
    Abstract: A device that includes an electronic device referred to as an integrated circuit interposer is disclosed. The integrated circuit includes a voltage regulator module. The interposer is attached to an electronic device, such as another integrated circuit, and facilitates control and distribution of power to the electronic device. The integrated circuit interposer can also conduct signaling between the attached electronic device and another electronic device. The voltage regulator module at the integrated circuit interposer can be configured to provide a voltage reference signal to the attached electronic device. Generation of the voltage reference signal by the integrated circuit interposer can be enabled or disabled and the value of the voltage reference signal can be adjusted, depending on operating requirements of the electronic device.
    Type: Application
    Filed: September 23, 2008
    Publication date: March 25, 2010
    Applicant: ADVANCED MICRO DEVICES, INC.
    Inventors: Stephen V. Kosonocky, Samuel D. Naffziger, Visvesh S. Sathe
  • Publication number: 20100052636
    Abstract: A constant-voltage circuit converts a voltage input to an input terminal and outputs a predetermined constant voltage from an output terminal. The constant-voltage circuit includes an output transistor to output an electrical current to the output terminal in response to a control signal, a reference voltage circuit to generate a predetermined reference voltage, a control circuit to adjust a voltage proportional to the output voltage output from the output terminal to the reference voltage output from the reference voltage circuit by controlling the output transistor and a soft start circuit including a capacitor for soft start that is charged at start-up and a current control unit to control an electrical current supplied to the reference voltage circuit. The current control unit adjusts the reference voltage to a voltage determined by the capacitor for soft start at the start-up until the reference voltage reaches a desired voltage.
    Type: Application
    Filed: August 25, 2009
    Publication date: March 4, 2010
    Applicant: RICOH COMPANY, LTD.
    Inventors: Yoshiki TAKAGI, Kenichi Watanabe
  • Publication number: 20100039082
    Abstract: Apparatus and methods for reducing output load transients of a low dropout voltage regulator (“LDO”) are disclosed herein. A voltage regulator includes an output driver coupled to a regulator output pin, the output driver provides current to a load external to the regulator. A clamping device is coupled between the output pin and an internal node of the regulator. The clamping device forces a voltage at a control input of the output driver to follow the voltage at the output pin when the output driver is disabled.
    Type: Application
    Filed: August 15, 2008
    Publication date: February 18, 2010
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Yong Xie, Gregory G. Romas, JR.
  • Patent number: 7656145
    Abstract: A voltage generator is used for generating a voltage reference with high power supply rejection. One embodiment of the circuit includes a voltage regulator and a bandgap voltage circuit and an amplifier. The voltage regulator including an input node is coupled to an external power supply for generating a regulated voltage source. A bandgap voltage circuit includes a first and a second resistor and a first and a second transistor to generate a voltage difference between the base-to-emitter voltages of the first and the second transistors. The second resistor is coupled to the first resistor and the first transistor for generating the first predetermined voltage in response to the voltage difference. An amplifier circuit is coupled to the first transistor of the bandgap voltage circuit for receiving a first amplifying signal and generating an amplified signal so as to regulate the regulated voltage source.
    Type: Grant
    Filed: June 19, 2007
    Date of Patent: February 2, 2010
    Assignee: O2Micro International Limited
    Inventors: Sean Xiao, Tom Tang, Guoxing Li
  • Patent number: 7656225
    Abstract: A voltage generation circuit comprises a reference voltage generation circuit; a differential amplifier; an output node; a P-channel MOS transistor; a first resistor series; a second resistor series; a third resistor series; and a selection control circuit. A reference voltage generated by the reference voltage generation circuit is input to a first input terminal of the differential amplifier. The first resistor series is connected between a drain of the P-channel MOS transistor and the output node. The second resistor series is connected between the output node and a second input terminal of the differential amplifier. The third resistor array is connected between the second input terminal of the differential amplifier and a ground. The selection control circuit controls such that a sum of the resistances of the first resistor series and the second resistor series is constant.
    Type: Grant
    Filed: April 24, 2007
    Date of Patent: February 2, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsuaki Isobe, Noboru Shibata
  • Patent number: 7638992
    Abstract: A drive power control device according to the present invention includes a transistor, which is input with a driving signal before current amplification into a base thereof, and which amplifies a current of the driving signal to drive an actuator; a switching element, which switches an input of a supply voltage to a collector of the transistor between on and off; and a voltage comparator, which compares a base voltage and a collector voltage of the transistor, and which controls the switching element such that the input of the supply voltage to the collector is turned off when a predetermined voltage difference occurs, and the input of the supply voltage to the collector is turned on when a predetermined voltage difference does not occur.
    Type: Grant
    Filed: January 24, 2007
    Date of Patent: December 29, 2009
    Assignee: Seiko Epson Corporation
    Inventor: Yasuhiko Kosugi
  • Patent number: 7619397
    Abstract: One embodiment of the present invention includes a system for providing a soft-start for a power regulator comprising a differential transistor pair that receives an input current and conducts a first current through a first transistor and a second current through a second transistor. One of the first and second current changes in response to a change in the other to maintain a sum of the first and second current being substantially equal to the input current. The system also comprises a comparator that provides an output signal based on a comparison of a first input voltage and a second input voltage associated with the first current and the second current, respectively. The system further comprises a current source activated by the output signal to charge a capacitor that increases a soft-start reference voltage associated with control of the power regulator and which controls the change in the other of the first and second current.
    Type: Grant
    Filed: November 6, 2007
    Date of Patent: November 17, 2009
    Assignee: Texas Instruments Incorporated
    Inventor: Mohammad A. Al-Shyoukh
  • Publication number: 20090273237
    Abstract: A regulator circuit stabilizes the input voltage applied to an input terminal before outputting the output voltage via an output terminal. An output transistor is provided between the input terminal and the output terminal. An error amplifier adjusts the voltage applied to the control terminal of the output transistor such that a voltage that corresponds to the output voltage approaches a predetermined reference voltage. A fluctuation detection capacitor is provided on a path from the input terminal to the grounded terminal. One terminal of the fluctuation detection capacitor is set to a fixed electric potential. In a case that the input voltage is lower than the voltage at the other terminal of the fluctuation detection capacitor, an undershoot suppressing circuit forcibly reduces the gate voltage of the output transistor.
    Type: Application
    Filed: December 6, 2006
    Publication date: November 5, 2009
    Applicant: ROHM CO., LTD.
    Inventor: Hiroki Inoue
  • Patent number: 7612549
    Abstract: An LDO with fast current limit includes P-type transistor, an error amplifier, an adjustable reference voltage circuit for generating an adjustable reference voltage, and an N-type transistor. The P-type transistor includes a first end coupled to the input voltage source, a second end for outputting an output voltage source, and a control end for receiving a current control signal in order to control the current of the output voltage source. The error amplifier generates the current control signal according to the reference voltage and a voltage divided from the output voltage source. N-type transistor includes a first end coupled to the output end of the error amplifier, a second end coupled to the input voltage source, and a control end for receiving the adjustable reference voltage. When the N-type transistor is turned on, the voltage of the current control signal is clamped by the adjustable reference voltage.
    Type: Grant
    Filed: November 13, 2008
    Date of Patent: November 3, 2009
    Assignee: Advanced Analog Technology, Inc.
    Inventors: Shun-Hau Kao, Mao-Chuan Chien
  • Patent number: 7589505
    Abstract: A power supply having a control circuit for controlling an output of the power supply, and a voltage monitor circuit for detecting a voltage at a first location and providing the detected voltage to a second location in the control circuit independent of any difference in ground voltage between the first location and the second location. The control circuit is configured to control the output of the power supply in response to the detected voltage provided by the voltage monitor circuit.
    Type: Grant
    Filed: June 14, 2005
    Date of Patent: September 15, 2009
    Assignee: Astec International Limited
    Inventor: Wing Ling Cheng
  • Patent number: 7579818
    Abstract: In one embodiment, a current regulator is configured to form a first signal representative of a current flow through a power switch and to use the first signal to determine an off-time of the power switch.
    Type: Grant
    Filed: July 28, 2005
    Date of Patent: August 25, 2009
    Assignee: Semiconductor Components Industries, L.L.C.
    Inventors: Alan R. Ball, David M. Heminger
  • Patent number: 7576524
    Abstract: In a constant voltage generating apparatus where an output circuit is controlled in accordance with a control voltage, a voltage detection signal generating circuit generates a voltage detection signal in accordance with a difference between an output voltage signal of the output circuit and a first reference signal. A current detection signal generating circuit generates a current detection signal in accordance with a difference between an output current signal of the output circuit and a second reference signal. A control current generating circuit generates a control current in accordance with the voltage detection signal and the current detection signal. A control current-to-control voltage converting circuit converts the control current into the control voltage.
    Type: Grant
    Filed: November 2, 2006
    Date of Patent: August 18, 2009
    Assignee: NEC Electronics Corporatioon
    Inventor: Tsukasa Ohoka
  • Patent number: 7557550
    Abstract: A technique includes using a first stored energy source to generate a reference signal to circuitry of a supply regulator in response to the regulator being in a startup state. The technique includes using an output signal that is provided by the regulator to generate the reference signal in response to the regulator not being in the startup state.
    Type: Grant
    Filed: November 14, 2005
    Date of Patent: July 7, 2009
    Assignee: Silicon Laboratories Inc.
    Inventors: Murthy R. Mellachurvu, Scott D. Willingham, Peter J. Vancorenland, G. Tyson Tuttle
  • Patent number: RE42335
    Abstract: A low-dropout regulator with a single-transistor-control providing improved transient response and stability is disclosed. The single-transistor-control provides a dynamic resistance at the output of the regulator for minimizing undershoot and overshoot, and hence improves transient response. Since the single-control transistor reduces the output resistance of the regulator, the output pole is pushed to a sufficiently high frequency without affecting stability. Therefore, the limited choice of combinations of the output capacitance and its equivalent-series-resistance is substantially relaxed.
    Type: Grant
    Filed: October 23, 2009
    Date of Patent: May 10, 2011
    Assignee: The Hong Kong University of Science and Technology
    Inventors: Tsz Yin Man, Chi Yat Leung, Ka Nang Leung, Philip Kwok Tai Mok, John Man Sun Chan