With A Specific Feedback Amplifier (e.g., Integrator, Summer) Patents (Class 323/280)
  • Patent number: 9078292
    Abstract: A monitoring system for monitoring the temperature of equipment, comprising a central digital computer, a MESH communication network, wherein the network feeds signals to the central digital computer, a plurality of heating elements for heating the equipment, temperature sensors adapted to measure the temperature of the equipment, wherein each sensor is adapted to provide a signal representing the temperature of the piece of equipment to which the sensor is associated, to the network, wherein each temperature sensor can also be used to control the electric heaters, a temperature sensor that monitors the ambient temperature of the facility, and current transducers associated with the heaters, to monitor the energy use and current loss of the heaters, wherein the central computer uses the data it receives from the other elements of the monitoring system to determine when the equipment is not at the correct temperature and diagnoses the reason why.
    Type: Grant
    Filed: October 1, 2008
    Date of Patent: July 7, 2015
    Inventor: Timothy R. Mullen
  • Patent number: 9052730
    Abstract: A voltage regulator calibration circuit including a voltage regulator and a calibration unit is provided. The voltage regulator regulates an output voltage according to a reference voltage and a feedback voltage. The feedback voltage is in direct proportion to the output voltage. The calibration unit is coupled to the voltage regulator. The calibration unit generates a control code through binary search according to the output voltage and a target voltage. The control code determines the proportion of the feedback voltage to the output voltage.
    Type: Grant
    Filed: November 14, 2012
    Date of Patent: June 9, 2015
    Assignee: Faraday Technology Corp.
    Inventors: Chi-Yang Chen, San-Yueh Huang
  • Patent number: 9052728
    Abstract: Methods and circuits related to power regulator start-up are disclosed. In one embodiment, a start-up circuit can include: (i) a delay circuit having a resistor and a capacitor, where the capacitor is coupled between ground and a common node; and (ii) a control chip that receives a reference voltage, and includes an input pin coupled to an input source, an output pin supplying power for a device, and a multiplexed pin coupled to the resistor at the common node to receive an enable signal. The start-up circuit outputs an electrical signal at the output pin based on a comparison of a voltage at the multiplexed pin against the reference voltage, and after a delay time determined by the capacitor and the reference voltage. The voltage at the multiplexed pin can increase continuously with a rising slope determined by input current flowing through the multiplexed pin during a start-up process.
    Type: Grant
    Filed: July 11, 2013
    Date of Patent: June 9, 2015
    Assignee: Silergy Semiconductor Technology (Hangzhou) LTD
    Inventor: Wei Chen
  • Patent number: 9048788
    Abstract: In a semiconductor device, power consumption is reduced. Further, a standby circuit is formed of a few elements, and thus increase in the circuit area of the semiconductor device is prevented. The standby circuit provided in the semiconductor device is formed of only one transistor and voltage supplied to the transistor is switched, whereby output current of the semiconductor device is controlled. As a result, the output current of the semiconductor device in a standby state can be substantially zero, so that the power consumption can be reduced. By using an oxide semiconductor for a semiconductor layer of a transistor, leakage current can be suppressed as low as possible.
    Type: Grant
    Filed: April 24, 2012
    Date of Patent: June 2, 2015
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Atsushi Hirose
  • Publication number: 20150137781
    Abstract: A low dropout (LDO) circuit capable of controlled startup and a method of controlling the same are disclosed herein. The LDO circuit includes an amplifier, a pass element, and a startup control circuit. The amplifier receives a feedback voltage determined by an output voltage and a predetermined reference voltage, and provides a first voltage determined by the feedback voltage and the reference voltage. The pass element is connected to an input power and an output node for providing the output voltage. The startup control circuit includes a current source, and forward one of the first voltage, provided by the amplifier based on the level of the output voltage, and a second voltage, generated using the current source, to the gate of the pass element.
    Type: Application
    Filed: January 9, 2015
    Publication date: May 21, 2015
    Inventors: Wanyuan Qu, Young Jin Woo, Jin Yong Jeon, Dae Keun Han, Young Suk Son
  • Publication number: 20150137780
    Abstract: A self-adjustable current source control circuit utilizes a replica output stage, a sink current source that generates a reference current, and a negative feedback circuit to generate a sink current between a linear regulator output terminal and ground only when a load circuit connected to the linear regulator is in a low power consuming state. The replica output stage includes an 1:N scaled replica of the linear regulator's NMOS (or NPN) output stage transistor, and the negative feedback circuit utilizes two PMOS (or PNP) negative feedback transistors having the same N:1 size ratio and connected as a common gate amplifier, whereby one of the two negative feedback transistors turns on to draw the desired sink current from the regulator output terminal only when the load current falls below N times the reference current (i.e., only the load current is drawn through the output stage transistor during high load current conditions).
    Type: Application
    Filed: November 19, 2013
    Publication date: May 21, 2015
    Applicant: Tower Semiconductor Ltd.
    Inventors: Valentin Lerner, Danny Pollak
  • Patent number: 9035631
    Abstract: The phase margin compensation method according to an exemplary embodiment of the present invention includes: outputting reference voltage (Vout2); outputting a first reference voltage (Vout1) actually supplied to the target circuit; comparing the reference voltage (Vout2) with the first reference voltage (Vout1) by the comparator; counting any section of an output signal (pulse signal) from the comparator by a predetermined frequency by the duty cycle calculator; and controlling a phase margin of a frequency of output voltage supplied to the target circuit by controlling buffer current based on the duty cycle ratios and the output bit information fed back from the duty cycle calculator.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: May 19, 2015
    Assignee: SAMSUNG ELECTRO-MECHANICS CO., LTD.
    Inventor: Soo Woong Lee
  • Publication number: 20150130434
    Abstract: A circuit and method for providing a current limiting feature in a low dropout (“LDO”) linear voltage regulator. A pass element generates an output voltage that is less than the input voltage. The pass element is normally enabled by an error amplifier that compares a feedback signal from the output of the pass element with a reference signal. However, the pass element may be enabled by a current limiting circuit that bypasses the error amplifier to limit the current generated at the output of the pass element.
    Type: Application
    Filed: July 30, 2014
    Publication date: May 14, 2015
    Inventors: Karan Singh Jain, Timothy Bryan Merkin, Susan Curtis
  • Patent number: 9030178
    Abstract: A power converter used in the current control circuit and control method, consisting of a converter, a voltage divider circuit, a current sampling circuit, a first gain circuit, a differential amplifier, a second gain circuit, a multiplier, a saw tooth wave generator, a modulation comparator, and a driver. The invention samples inductor current through the current sampling circuit and generates the current sense signal, then processes again. With the differential amplifier, it compares the feedback voltage from the voltage divider circuit with the reference voltage, and the results along a modulation comparator output a drive signal to control the duty cycle in order to avoid the generation of inrush current. The present invention avoids inrush current caused by the large drive signal and achieves a good response rate and better system stability.
    Type: Grant
    Filed: August 26, 2013
    Date of Patent: May 12, 2015
    Assignee: Luxmill Electronic Co., Ltd.
    Inventors: Yu-Cheng Chang, Mao-feng Lan, Chung-hung Lin
  • Patent number: 9030179
    Abstract: A switching regulator circuit includes a power stage and a compensation network. The compensation network includes a programmable transconductance (gm), having a first selectable transconductance such a closed loop transfer function of the switching regulator circuit may be characterized by a first transfer function having a having a first DC open loop gain and a first bandwidth, and by a second transfer function having a second DC open loop gain and a second bandwidth.
    Type: Grant
    Filed: July 23, 2012
    Date of Patent: May 12, 2015
    Assignee: QUALCOMM, Incorporated
    Inventor: Zhaohui Zhu
  • Publication number: 20150123634
    Abstract: An integrated regulator, in particular a voltage regulator, for a personal protection arrangement in a vehicle, includes a regulating element that converts an input signal into an output signal having a defined value, and a control application circuit that applies control to the regulating element to generate the output signal having the defined value. The control application circuit outputs the output signal via the regulating element with at least two different selectable values as a function of a specifying signal, such that for selection of the value of the output signal, a configuration circuit receives at least one configuration signal and, as a function of a configuration ascertained in the context of evaluation, selects one of at least two different specifying signals and applies it to the control application circuit to output the output signal having the selected value.
    Type: Application
    Filed: May 14, 2013
    Publication date: May 7, 2015
    Inventors: Carsten List, Hartmut Schumacher, Falko Sievers
  • Patent number: 9024602
    Abstract: The regulator with low dropout voltage comprises an error amplifier and an output stage comprising an output transistor and a buffer circuit comprising an input connected to the output node of the error amplifier, an output connected to the output transistor, a follower amplifier connected between the input and the output of the buffer circuit. The buffer circuit furthermore comprises a transistor active load connected to the output of the follower amplifier and a negative feedback amplifier arranged in common gate configuration and connected between the output of the follower amplifier and the gate of the transistor of the active load.
    Type: Grant
    Filed: March 21, 2013
    Date of Patent: May 5, 2015
    Assignee: STMicroelectronics (Rousset) SAS
    Inventors: Jimmy Fort, Thierry Soude
  • Patent number: 9024601
    Abstract: A voltage converting apparatus is disclosed. The voltage converting apparatus includes a pulse width modulation (PWM) signal generating circuit, a power transistor, a first inductor, a second inductor and a feedback rectifier. The PWM signal generating circuit receives a feedback power to be an operating power and generates a PWM signal. A first terminal of the power transistor receives an input voltage, and a control terminal of the power transistor receives the PWM signal. The second inductor couples with a voltage on the first inductor and generates a coupling voltage. The feedback rectifier rectifies the coupling voltage to generate a feedback power.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: May 5, 2015
    Assignee: Excelliance MOS Corporation
    Inventor: Yung-Chen Lu
  • Publication number: 20150115918
    Abstract: Methods and apparatus for a dynamic bias generator are provided. In an example, a dynamic bias generator for a voltage regulator can include a slope generator and a peak detector coupled to the slope generator. In certain examples, the slope generator and the peak detector can receive a representation of output current of the voltage regulator and can adjust a bias control voltage at an output of the peak detector in response to a change in the output current of the voltage regulator.
    Type: Application
    Filed: October 24, 2014
    Publication date: April 30, 2015
    Inventor: Juha Joonas Oikarinen
  • Patent number: 9018576
    Abstract: Disclosed is a low drop-out voltage regulator circuit with a distributed output network coupled to a pixel array for use in image sensor circuitry. The regulator circuit comprises voltage regulating circuitry and a distributed output network, wherein the distributed output network comprises drive transistors disposed along and connected between a supply track and an output track. The spatial distribution of the drive transistors improves heat dissipation within the regulator circuit, and a combination of low current flow and regulated output voltage reduces IR drop across the output track. The improved heat dissipation increases device lifespan and performance, whereas the reduction in IR drop across the output track provides better pixel response, readout uniformity, and image quality.
    Type: Grant
    Filed: May 10, 2011
    Date of Patent: April 28, 2015
    Assignee: STMicroelectronics Asia Pacific Pte Ltd
    Inventors: Jingfeng Gong, Yann Desprez-le-Goarant
  • Patent number: 9000743
    Abstract: A multi-channel constant voltage and constant current converting controller is provided. It comprises a multi-channel balance circuit and an error amplifier circuit. The multi-channel balance circuit receives a first voltage signal and load current detecting signals and outputs a second voltage signal and amplifying load current detecting signals. The error amplifier circuit receives the second voltage signal, the amplifying load current detecting signals and a reference voltage and outputs an error amplifying signal. The error amplifier circuit outs the error amplifying signal according to the reference voltage and the maximum value between the second voltage signal and amplifying load current detecting signals.
    Type: Grant
    Filed: October 4, 2012
    Date of Patent: April 7, 2015
    Assignee: Green Solution Technology Co., Ltd.
    Inventor: Ming-Chiang Ting
  • Publication number: 20150084609
    Abstract: A circuit may include a differential amplifier and a feedback network. The feedback network may have a chain of resistance sets coupled in series, with a first end terminal coupled to an output terminal of the differential amplifier and a second end terminal coupled to a power reference terminal of the differential amplifier. Respective nodes may be coupled between successive ones of the resistance sets. A feedback terminal may be coupled to an inverting input terminal of the differential amplifier. A controller may control a set of switches to electrically couple a given node to the feedback terminal. A first resistance set of the chain adjacent the first end terminal may be two resistance subsets coupled in series, with an intermediate node coupled therebetween. A programmable current generator may have a current output coupled to the intermediate node and may produce a controlled current flowing at the current output terminal.
    Type: Application
    Filed: September 22, 2014
    Publication date: March 26, 2015
    Applicant: STMICROELECTRONICS INTERNATIONAL N.V.
    Inventors: Alexandre Pons, Karel Napravnik
  • Publication number: 20150077076
    Abstract: A dual mode low dropout voltage regulator has a low dropout regulation mode and a bypass mode and provides a smooth transition between mode transitions taking place under load. When an accessory requires a larger voltage level, a bypass signal commands the dual mode low dropout voltage regulator to go into bypass mode and transfer voltage level of the unregulated input voltage source to the output of the dual mode low dropout voltage regulator. The dual mode low dropout voltage regulator provides a smooth transition to the bypass to prevent the output of the dual mode low dropout voltage regulator from decreasing or having a “brown out” until a pass transistor is forced to turn on fully to provide the voltage level of the unregulated input voltage source to fully bypass the low dropout regulating mode of operation.
    Type: Application
    Filed: September 19, 2013
    Publication date: March 19, 2015
    Applicant: Dialog Semiconductor GmbH
    Inventor: Ambreesh Bhattad
  • Patent number: 8981840
    Abstract: A pass device configured from a common gate transistor, wherein an input voltage is applied to the source and an output at the drain is applied to a load. The input resistance of the pass device increases as the input voltage is reduced and limits the useful range of the input voltage. Increasing the gate to source voltage (Vgs) by applying a negative voltage to the gate reduces the input resistance and increases the range of operation of the pass device.
    Type: Grant
    Filed: September 17, 2013
    Date of Patent: March 17, 2015
    Assignee: Dialog Semiconductor GmbH
    Inventors: Julian Tyrrell, Ambreesh Bhattad
  • Patent number: 8981747
    Abstract: The regulator has a differential circuit that generates a comparison signal corresponding to the difference between an input voltage and a voltage related to the output voltage, a first transistor that adjusts the output voltage in accordance with the comparison signal, a first current mirror circuit connected to a pair of differential output lines of the differential circuit, a second transistor that amplifies the high frequency signal superposed on the output voltage and sends the amplified signal to one of the differential output lines, a second current source that feeds current for amplifying the high frequency signal to the second transistor, a first capacitor, which accumulates charge therein as a result of the high frequency signal and controls the current flowing to one the pair of differential output lines via the second transistor in accordance with the charge quantity, and a second capacitor connected to the output voltage line.
    Type: Grant
    Filed: August 9, 2012
    Date of Patent: March 17, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Saito, Yuichi Goto
  • Patent number: 8981746
    Abstract: A low-dropout linear regulator includes an error amplifier which includes a cascaded arrangement of a differential amplifier and a gain stage. The gain stage includes a transistor driven by the differential amplifier to produce at a drive signal for an output stage of the regulator. The transistor is interposed over its source-drain line between a first resistive load included in a RC network creating a zero in the open loop gain of the regulator, and a second resistive load to produce a drive signal for the output stage of the regulator. The second resistive load is a non-linear compensation element to render current consumption linearly proportional to the load current to the regulator. The first resistive load is a non-linear element causing the frequency of said zero created by the RC network to decrease as the load current of the regulator decreases.
    Type: Grant
    Filed: March 15, 2012
    Date of Patent: March 17, 2015
    Assignee: STMicroelectronics Design and Application S.R.O.
    Inventor: Karel Napravnik
  • Patent number: 8975882
    Abstract: A regulating circuit includes a first comparator configured to control a turning on and a turning off of a first transistor based on a first comparison a reference voltage to a feedback voltage. The first transistor is coupled between an output node and a first voltage supply. A second comparator is configured to control a turning on and a turning off of a second transistor based on a second comparison of the reference voltage to the feedback voltage. The second transistor is coupled to the output node. A high-impedance circuit is coupled in series with the second transistor such that the high-impedance block is disposed between the second transistor and a second power supply. The high-impedance circuit is configured to generate a constant current between the output node and the second voltage supply when the second transistor is turned on.
    Type: Grant
    Filed: October 31, 2012
    Date of Patent: March 10, 2015
    Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventor: Chih-Feng Li
  • Patent number: 8975883
    Abstract: A soft start circuit includes an error amplifier for generating a control signal according to an input voltage, a feedback voltage and a reference voltage, a feedback circuit for generating the feedback voltage according to an output voltage, an internal voltage source for generating a soft start voltage, and a sink circuit including a first transformation module for generating a first transformation current according to the soft start voltage, a second transformation module for generating a second transformation current according to the feedback voltage, a comparison module coupled to the first transformation module and the second transformation module for generating a comparison result according to the first transformation current and the second transformation current, and an output module coupled to the comparison module for generating a sink current according to the comparison result, so as to control the control signal.
    Type: Grant
    Filed: August 27, 2012
    Date of Patent: March 10, 2015
    Assignee: Anpec Electronics Corporation
    Inventors: Chih-Ning Chen, Yen-Ming Chen
  • Publication number: 20150061623
    Abstract: There are provided a voltage regulator of a low-drop-output type, and an operation method of the same. The voltage regulator includes: an error amplifying unit providing a gate signal according to a voltage difference between a reference voltage and a feedback voltage; a semiconductor switch regulating a current between a supply voltage terminal and a ground according to the gate signal; a voltage detecting unit detecting the supply voltage to provide a detected voltage; a feedback control unit providing a feedback control signal according to the detected voltage; and a feedback voltage regulating unit connected between the semiconductor switch and the ground to regulate the feedback voltage according to the feedback control signal.
    Type: Application
    Filed: November 22, 2013
    Publication date: March 5, 2015
    Applicant: SAMSUNG ELECTRO-MECHANICS CO., LTD.
    Inventor: Soo Woong LEE
  • Publication number: 20150061622
    Abstract: A low dropout (LDO) regulator with a limited startup inrush current is disclosed. The LDO includes a power source, error amplifier, pass transistor, feedback network, and a current limit control whose input is electrically connected to the pass transistor and the electrical output of the error amplifier and whose output limits current during startup. The LDO can include a current control limit comparator including a power source, and output of the pass transistor. The LDO can also include a bypass mode current control limit comparator having a first input voltage of the error amplifier, and a second input voltage from the error amplifier.
    Type: Application
    Filed: September 9, 2013
    Publication date: March 5, 2015
    Applicant: Dialog Semiconductor GmbH
    Inventor: Ambreesh Bhattad
  • Publication number: 20150061621
    Abstract: A circuit including a low drop-out regulator (LDO) has a current control loop configured and connected to detect whether an external capacitor is connected to the output of the LDO. The current control loop includes a differential amplifier, a current source capable to output different reference currents and a small MOS transistor. The circuit may be operated in an output capacitor detection mode when started and in a regulated voltage source mode otherwise. In the output capacitor detection mode, the small MOS transistor is driven by the differential amplifier and drives the LDO's power MOS transistor depending on a difference between a current through the small MOS transistor and the reference current output by the current source. Components of the current control loop may be used during regulated voltage source mode for short circuit protection.
    Type: Application
    Filed: September 5, 2013
    Publication date: March 5, 2015
    Inventor: Alexandre PONS
  • Patent number: 8970189
    Abstract: A voltage generation circuit supplies an internal power supply voltage to an internal circuit via an output terminal and includes a regulator, a second drive element, and a control circuit. The regulator includes a first drive element disposed between an external power supply VDD (first power supply) and an output terminal, and supplies a voltage based on a reference voltage to the output voltage by controlling the first drive element. The second drive element is disposed between the external power supply VDD and the output terminal, and supplies a voltage of the external power supply VDD to the output terminal when activated. When a voltage of the external power supply is a previously set detection voltage value or less, the control circuit activates the first and the second drive element, and when the voltage of the external power supply exceeds the detection voltage value, deactivates the second drive element.
    Type: Grant
    Filed: August 9, 2012
    Date of Patent: March 3, 2015
    Assignee: Renesas Electronics Corporation
    Inventor: Shingo Nakashima
  • Patent number: 8970197
    Abstract: A voltage regulator circuit includes a plurality of transistors and a control circuit. Each transistor has two source/drain terminal and a gate terminal. One source/drain terminal of each transistor is electrically coupled to a source voltage, and the other source/drain terminals of the transistors are electrically coupled to each other and corporately referred to as an output terminal of the voltage regulator circuit. The control circuit is electrically coupled to the gate terminals of the transistors and configured to determine the number of the transistors to be turned on according to the difference between the voltage at the output terminal and a predetermined reference voltage.
    Type: Grant
    Filed: August 3, 2012
    Date of Patent: March 3, 2015
    Assignee: United Microelectronics Corporation
    Inventor: Shi-Wen Chen
  • Patent number: 8957648
    Abstract: An output switching circuit includes a switching circuit having a first transistor connected to a high-voltage power supply, a second transistor connected to a low-voltage power supply, and an output terminal at a connection node between the first and second transistors; a comparison unit that compares an input signal with a feedback signal obtained by feedback of an output signal of the output terminal via a low-pass filter to generate a comparison signal; and a drive pulse generating unit that generates first drive pulses for driving the first transistor and second drive pulses for driving the second transistor in accordance with the comparison signal.
    Type: Grant
    Filed: May 27, 2011
    Date of Patent: February 17, 2015
    Assignee: Spansion LLC
    Inventors: Takeshi Wakii, Akihito Yoshioka
  • Patent number: 8952619
    Abstract: A distributed system for driving strings of series-connected LEDs for backlighting, display and lighting applications includes multiple intelligent satellite LED driver ICs connected to a an interface IC via serial bus. The interface IC translates information obtained from a host microcontroller into instructions for the satellite LED driver ICs pertaining to such parameters as duty factor, current levels, phase delay and fault settings. Fault conditions in the LED driver ICs can be transmitted back to, the interface IC. An analog current sense feedback system which also links the LED driver ICs determines the supply voltage for the LED strings.
    Type: Grant
    Filed: January 10, 2012
    Date of Patent: February 10, 2015
    Assignee: Advanced Analogic Technologies Incorporated
    Inventors: Richard K. Williams, Kevin D'Angelo, David A. Brown, George A. Hariman
  • Patent number: 8947125
    Abstract: A comparator circuit comprising an operational amplifier configured to compare a difference between a switching voltage and a reference voltage, and a dynamically adjustable bias current generator coupled to the operational amplifier. A method of conserving power in a comparator circuit includes estimating a switching regulator load current value, communicating the value to a current bias generator, enabling the bias generator with a signal from a switching regulator PFM logic circuit, and establishing a bias current at an operational amplifier of the comparator circuit on the basis of the enabling.
    Type: Grant
    Filed: February 21, 2013
    Date of Patent: February 3, 2015
    Assignee: QUALCOMM Incorporated
    Inventor: Vijayakumar Dhanasekaran
  • Patent number: 8947060
    Abstract: An embodiment of the invention relates to a power converter formed with an error amplifier and a related method. In an embodiment, a first switch is coupled in series with an error amplifier compensation capacitor. Upon detection of a current level greater than a threshold level, the compensation capacitor is decoupled from the error amplifier by opening the first switch. In an embodiment, a second switch is coupled in parallel with the compensation capacitor, and the current-sensing circuit enables conductivity of the second switch to discharge the compensation capacitor upon detection of the current level greater than the threshold level. The second switch is opened upon detection of the current level less than the threshold level. In an embodiment, the current-sensing circuit controls an output current of the power converter at a current-limit level upon detection of the internal current level greater than the threshold level.
    Type: Grant
    Filed: November 23, 2010
    Date of Patent: February 3, 2015
    Assignee: STMicroelectronics (Shenzhen) R&D Co., Ltd.
    Inventors: Da Song Lin, Ni Zeng, Gang Zha, Xianfeng Xiong, Yiwei Zhang
  • Publication number: 20150028835
    Abstract: A DC-to-DC converter includes an error integrator that further includes a first amplifier and a second amplifier that each includes a first input for receiving a reference voltage and a second input for receiving a feedback voltage, a capacitor to an output of the second amplifier, and a resistor including a first end being coupled to an output of the first amplifier and a second end being coupled to the capacitor.
    Type: Application
    Filed: July 26, 2013
    Publication date: January 29, 2015
    Applicant: ANALOG DEVICES, INC.
    Inventors: Sejun Kim, Khiem Quang Nguyen
  • Patent number: 8941320
    Abstract: A method of driving a light source includes outputting a variable driving voltage to a light source part, sensing a first voltage based on the driving voltage and developed at a first end of the light source part, sensing a second voltage developed at a second end of the light source part due to current passing through the light source part and adjusting the driving voltage while using the first and second voltages so that power consumption by the light source part is substantially constant irrespective of temperature of the light source part and/or irrespective of a duty cycle ration being used to drive the light source part. Thus, a luminance of the light source part may be maintained at substantially uniform levels.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: January 27, 2015
    Assignee: Samsung Display Co., Ltd.
    Inventors: Min-Soo Choi, Won-Sik Oh, Eun-Chul Shin
  • Publication number: 20150022166
    Abstract: A low-dropout voltage regulator includes a power transistor configured to receive an input voltage and to provide a regulated output voltage at an output voltage node. The power transistor includes a control electrode configured to receive a driver signal. A reference circuit is configured to generate a reference voltage. A feedback network is coupled to the power transistor and is configured to provide a first feedback signal and a second feedback signal. The first feedback signal represents the output voltage and the second feedback signal represents an output voltage gradient. An error amplifier is configured to receive the reference voltage and the first feedback signal representing the output voltage. The error amplifier is configured to generate the driver signal dependent on the reference voltage and the first feedback signal. The error amplifier includes an output stage that is biased with a bias current responsive to the second feedback signal.
    Type: Application
    Filed: October 3, 2014
    Publication date: January 22, 2015
    Inventors: Giovanni Bisson, Marco Flaibani, Marco Piselli
  • Publication number: 20150015224
    Abstract: A power supply circuit includes a transistor disposed between an input terminal to which an input voltage is applied and an output terminal to which an output voltage is applied, and an error amplifier configured to compare a feedback voltage varied based on the output voltage and a reference voltage, and control the transistor based on a result of the comparison, the reference voltage being generated by selectively using the input voltage or the output voltage.
    Type: Application
    Filed: July 10, 2014
    Publication date: January 15, 2015
    Inventor: Makoto Yasusaka
  • Publication number: 20150015223
    Abstract: A device includes an error amplifier, a standby current source, a charging current source, a voltage divider, and a first switch. The error amplifier has a negative input terminal and a positive input terminal. The standby current source has a control terminal electrically connected to an output terminal of the error amplifier. The voltage divider has an input terminal electrically connected to an output terminal of the standby current source, and an output terminal electrically connected to the positive input terminal of the error amplifier. The charging current source has a control terminal electrically connected to the output terminal of the error amplifier. The first switch has a first terminal electrically connected to an input terminal of the charging current source, and a second terminal electrically connected to a first power supply node.
    Type: Application
    Filed: July 15, 2013
    Publication date: January 15, 2015
    Inventors: Jerry Chen, Cheng-Hsiung Kuo, Yue-Der Chih
  • Patent number: 8933634
    Abstract: A distributed system for driving strings of series-connected LEDs for backlighting, display and lighting applications includes multiple intelligent satellite LED driver ICs connected to a an interface IC via serial bus. The interface IC translates information obtained from a host microcontroller into instructions for the satellite LED driver ICs pertaining to such parameters as duty factor, current levels, phase delay and fault settings. Fault conditions in the LED driver ICs can be transmitted back to the interface IC. An analog current sense feedback system which also links the LED driver ICs determines the supply voltage for the LED strings.
    Type: Grant
    Filed: January 10, 2012
    Date of Patent: January 13, 2015
    Assignee: Advanced Analogic Technologies Incorporated
    Inventors: Richard K. Williams, Kevin D'Angelo, David A. Brown, George A. Hariman
  • Patent number: 8928296
    Abstract: A low dropout voltage regulator (LDO) includes first and second amplifiers and a current mirror. The first amplifier includes a first input receiving a reference voltage and a second input receiving a voltage proportional to an output of the LDO. The current mirror includes an input current at a first end of the current mirror to an output current at a second end of the current mirror, the input current controlled by an output of the first amplifier and the output current being supplied to the output of the LDO. The second amplifier includes a first input coupled to the first end of the current mirror and a second input coupled to the second end of the current mirror.
    Type: Grant
    Filed: May 20, 2011
    Date of Patent: January 6, 2015
    Assignee: Analog Devices, Inc.
    Inventors: Santiago Iriarte, Alberto Marinas
  • Patent number: 8922179
    Abstract: A low dropout (LDO) voltage regulator includes a voltage regulation loop for providing a gate drive signal to an output device, the gate drive signal proportional to an output current. The voltage regulation loop includes a current bias input for receiving a bias current. The LDO voltage regulator further includes a current bias control circuit for providing the adaptive bias current at a first value that is proportional to current limit value lab and the width-to-length ratio of transistors of the transconductance amplifier when the output current less than or equal to a threshold and increases the bias current from a threshold to a current limit value. The output current varies substantially linearly over a range of output current values between the threshold and the current limit value.
    Type: Grant
    Filed: December 12, 2011
    Date of Patent: December 30, 2014
    Assignee: Semiconductor Components Industries, LLC
    Inventor: Petr Kadanka
  • Publication number: 20140375289
    Abstract: The present document relates to multi-stage amplifiers, such as linear regulators or linear voltage regulators (e.g. low-dropout regulators) configured to provide a constant output voltage subject to load transients. A multi-stage amplifier is described, having a differential amplification stage configured to provide a stage output voltage at an output node, based on a first input voltage and a second input voltage. Furthermore, the multi-stage amplifier comprises a second amplification stage comprising an amplifier current source configured to provide an amplifier current; and an amplifier transistor arranged in series with the amplifier current source; wherein a gate of the amplifier transistor is coupled to the output node of the differential amplification stage. In addition, the multi-stage amplifier comprises a detection circuit.
    Type: Application
    Filed: February 27, 2014
    Publication date: December 25, 2014
    Applicant: Dialog Semiconductor GmbH
    Inventors: Frank Kronmueller, Mahir Uka
  • Patent number: 8917071
    Abstract: There is provided a regulator circuit capable of increasing the capacity of the output transistor for supplying current, stably generating an internal power supply voltage and adapting to the reduction of a power supply voltage. The regulator circuit includes an output transistor which is supplied with an external power supply voltage and supplies dropped voltage to an internal circuit, a differential amplifier for outputting a gate potential applied to the gate of the output transistor, a reference voltage generating circuit for supplying a reference voltage to the differential amplifier, and a cut-off transistor for turning off the output transistor to stop supplying power to the internal circuit. The output transistor is comprised of a depression NMOS transistor whose threshold voltage is a negative voltage. The regulator circuit further includes substrate potential control means for controlling the substrate potential of the depression NMOS transistor.
    Type: Grant
    Filed: April 11, 2013
    Date of Patent: December 23, 2014
    Assignee: Renesas Electronics Corporation
    Inventor: Hiromi Notani
  • Patent number: 8917069
    Abstract: A low dropout voltage regulator circuit that dynamically adjusts its output voltage has a voltage adjustment circuit in communication with a dynamic voltage controlling circuit for modifying the output voltage of the low dropout voltage regulator. A first amplification circuit is connected to receive an adjusted reference voltage from the voltage adjustment circuit and compare it with a feedback signal from the output voltage to provide a drive signal to a signal input terminal of a follower output transistor. An output terminal of the follower output transistor provides the output voltage of the regulation circuit. An adjustable internal load circuit applies a load current to the output terminal of the follower output transistor to increase the bandwidth of the output of the voltage regulation circuit that is sensed by a dynamic biasing sensing circuit to generate a dynamic biasing signal that modifies the bandwidth of the first amplification circuit.
    Type: Grant
    Filed: June 10, 2011
    Date of Patent: December 23, 2014
    Assignee: Dialog Semiconductor GmbH
    Inventors: Rupert Howes, Alexandre Tavares, Anthony Clowes, Mark Childs
  • Publication number: 20140368176
    Abstract: In an embodiment, an electronic includes a feedback-coupled circuit stage and a compensation circuit stage. The feedback-coupled stage is configured to drive a load, and the compensation stage is coupled to the feedback-coupled stage such that a combination of the compensation and feedback-coupled stages has a frequency response including a first root and an opposite second root that depend on the load. For example, an embodiment of such an electronic circuit may be a low-dropout (LDO) voltage regulator that lacks a large output capacitance for forming a dominant pole to stabilize the regulator. The regulator includes a feedback-coupled stage that generates and regulates an output voltage, and includes a compensation stage that is designed such that the frequency response of the regulator includes a zero that tracks a non-dominant output pole of the regulator so that the output pole does not adversely affect the stability of the regulator.
    Type: Application
    Filed: June 12, 2013
    Publication date: December 18, 2014
    Inventors: Pralay MANDAL, Sajal Kumar MANDAL
  • Patent number: 8912772
    Abstract: A low drop-out (LDO) voltage regulator which parallels a second pass device to a first pass device, where the second pass device has in series a small resistor. The small value resistor is a substitute for bond wires or capacitors with very low equivalent series resistances (ESR). A fast feedback loop is coupled to the junction of the second pass device and the small resistor and provides, via a Miller capacitor, a feedback signal to the amplifier of the voltage regulator. The added second pass device returns circuit stability by moving the fast-loop high frequency zero node back within the bandwidth of the circuit.
    Type: Grant
    Filed: April 19, 2011
    Date of Patent: December 16, 2014
    Assignee: Dialog Semiconductor GmbH
    Inventor: Mark Childs
  • Publication number: 20140340060
    Abstract: Devices and methods are provided for generating a regulated output voltage with improved line rejection based on an input voltage and a reference voltage. The device may include a pass transistor and a replica transistor, wherein source ports of the pass transistor and the replica transistor are coupled to the input voltage, a drain port of the pass transistor is coupled to the output voltage, and a gate port of the pass transistor is coupled to a gate port of the replica transistor. The device may further include a coupling circuit configured to couple current from the drain port of the replica transistor to the gate port of the replica transistor, the coupling circuit further configured to control voltage on the drain port of the replica transistor based on the reference voltage.
    Type: Application
    Filed: May 16, 2013
    Publication date: November 20, 2014
    Inventor: Peter Capofreddi
  • Publication number: 20140344589
    Abstract: Methods and systems to regulate a voltage with multiple selectable voltage regulator (VR) modes, using multiple corresponding circuits and/or a configurable circuit. The circuit may be configurable for one or more of a power-gate VR mode, a switched-capacitor VR (SCVR) mode, and a linear mode, such as a low drop-out (LDO) VR mode. A feedback controller, such as a proportional-integral-derivative (PID) controller, may configure and/or control a multi-mode VR for a selected VR mode. The feedback controller may select a VR mode based on a reference voltage and voltage ranges associated with the VR modes. The circuit may be configurable as banks of VRs, and the controller may be implemented to transition between VR modes by switching sub-banks between modes until the transition is complete.
    Type: Application
    Filed: December 21, 2012
    Publication date: November 20, 2014
    Inventors: Ramnarayanan Muthukaruppan, Pradyumna Agashe, Uday Bhaskar Kadali, Jnaneshwar Madugonda
  • Patent number: 8884595
    Abstract: In a power supply circuit, an error amplifier controls a main transistor based on a detection voltage according to an output voltage and a reference voltage corresponding to a target voltage of the output voltage such that the output voltage coincides with the target value. A phase compensation circuit for the power supply circuit includes a level shift circuit and a phase compensation capacitor. The level shift circuit generates a shift voltage by shifting a dc component of the output voltage toward a ground potential by a predetermined voltage, and outputs the shift voltage from an output terminal of the level shift circuit. The phase compensation capacitor is disposed on a route between the output terminal of the level shift circuit and an input terminal of an amplifier circuit of the error amplifier.
    Type: Grant
    Filed: November 26, 2012
    Date of Patent: November 11, 2014
    Assignee: DENSO CORPORATION
    Inventor: Takashi Imura
  • Patent number: 8884594
    Abstract: Provided is a voltage regulator having improved overshoot characteristics. In the voltage regulator, a current limiting circuit formed of, for example, a constant current source is provided in series to an output transistor, to thereby limit an output overcurrent. Further, a voltage limiting circuit formed of, for example, a diode is provided to an output terminal, to thereby limit an output voltage.
    Type: Grant
    Filed: February 13, 2012
    Date of Patent: November 11, 2014
    Assignee: Seiko Instruments Inc.
    Inventor: Masakazu Sugiura
  • Patent number: 8884604
    Abstract: A current mirror for generating a substantially identical current flow in two parallel current paths, each current path comprising a switching device and each switching device comprising first and second active terminals and a control terminal for controlling current flow between the first and second active terminals, the current mirror comprising a first switching device arranged such that its first active terminal is arranged to receive a first voltage, its second active terminal is arranged to receive a variable voltage that varies independently of the first voltage and its control terminal is arranged to receive a control voltage, a second switching device connected such that its first active terminal is arranged to receive the first voltage and its control terminal is arranged to receive the control voltage and a voltage control device connected to the second switching device such that an input of the voltage control device is connected to the second active terminal of the second switching device, the vo
    Type: Grant
    Filed: November 6, 2007
    Date of Patent: November 11, 2014
    Assignee: Cambridge Silicon Radio Limited
    Inventor: Jens Bertolt Zolnhofer