For Current Stabilization Patents (Class 323/312)
  • Publication number: 20140145643
    Abstract: The present application describes a current regulator for providing a regulated current from an input voltage. The current regulator comprises a voltage regulator circuit, operable to provide a regulated voltage, which comprises a plurality of Zener diodes connected in parallel.
    Type: Application
    Filed: June 22, 2012
    Publication date: May 29, 2014
    Applicant: ACCURIC LTD.
    Inventor: Dave Bannister
  • Publication number: 20140139134
    Abstract: The present invention relates to reference voltage regulating methods and circuits for a constant current driver. In one embodiment, a method can include: setting a reference voltage circuit matching with a current output channel of a constant current source; setting a first resistor of the reference voltage circuit to follow an ideal equivalent resistor of the current output channel, and maintaining a proportion of the first resistor and the ideal equivalent resistor to be no less than a predetermined value M; setting a first current of the reference voltage circuit to follow an ideal output current of the current output channel, and maintaining a proportion of the first current and the ideal output current to be no less than 1/M; and setting a product of the first current and the first resistor to be a reference voltage of the reference voltage circuit.
    Type: Application
    Filed: January 24, 2014
    Publication date: May 22, 2014
    Applicant: Silergy Semiconductor Technology (Hangzhou) LTD
    Inventor: Shuai Cheng
  • Patent number: 8729815
    Abstract: A current control system, and method for controlling current, and a lighting system including the same, are provided. The current control system includes front end circuitry to receive an input voltage and provide a regulated DC voltage to current source circuitry via a first input voltage terminal. Dimming interface circuitry provides a pulse width modulation signal to conversion circuitry, which uses the pulse width modulation signal to generate an analog voltage. The conversion circuitry sends the analog voltage to the current source circuitry via a second input voltage terminal. The current source circuitry uses the regulated DC voltage and the analog voltage to create an output current. The output current drives a load, which, in the lighting system, is one or more solid state light sources.
    Type: Grant
    Filed: March 12, 2012
    Date of Patent: May 20, 2014
    Assignee: OSRAM SYLVANIA Inc.
    Inventors: Ankit Sanghvi, Biju Antony, Chaim Becerra
  • Patent number: 8729883
    Abstract: A current source with low power consumption and reduced on-chip area occupancy. The current source for providing a constant current to a load includes a first circuit that generates a reference current. The first circuit includes a first plurality of interconnected transistors. The current source also includes a characteristic resistor, coupled to the first circuit, that determines value of the reference current. The current source further includes a second circuit and a third circuit. The second circuit, coupled to the first circuit and to the load, generates an output current that is identical to the reference current. The second circuit includes a second plurality of interconnected transistors. The third circuit, coupled to the first circuit, drives a multiple of the reference current into the characteristic resistor. The third circuit includes a third plurality of interconnected transistors.
    Type: Grant
    Filed: June 29, 2011
    Date of Patent: May 20, 2014
    Assignee: Synopsys, Inc.
    Inventors: Yanyi L. Wong, Agustinus Sutandi
  • Publication number: 20140132312
    Abstract: Driver circuitry and methods are provided for driving a semiconductor device. The driver circuitry includes a buck converter configured to generate a baseline current, and a capacitor coupled between an output of the buck converter and ground, the capacitor configured to store charge during an off-state of the buck converter and to discharge the stored charge as a peak current during an on-state of the buck converter, wherein the baseline current reaches a current limit prior to the capacitor being fully discharged, and an output current at an output of the buck converter is based, at least in part, on the baseline current and the peak current.
    Type: Application
    Filed: November 15, 2013
    Publication date: May 15, 2014
    Applicant: Fairchild Semiconductor Corporation
    Inventor: Laszlo Balogh
  • Publication number: 20140125307
    Abstract: A method and apparatus for self-referenced Alternating Current (AC) voltage chopping using non-linear dual switches configured in series with the Load to regulate voltage according to a positive or negative instantaneous voltage value and a positive going or negative going state is disclosed. Power applied to inductive Loads is conserved by automatically tracking the current demand of the Load and reusing the reactive energy held by the Load. A source AC power signal is converted to a representative digital logic square wave pulse signal referenced to ground, and conditioned for precision timing of power and regeneration switching circuits. Power and regeneration switching circuits are differential circuits referenced only to themselves. These floating circuits are not Direct Current circuits and are never referenced to ground or any specific voltage. The value of the source voltage is irrelevant because the differential voltage is re-routed on to itself.
    Type: Application
    Filed: November 2, 2012
    Publication date: May 8, 2014
    Inventor: Fred Verd
  • Patent number: 8716950
    Abstract: Data may be encoded onto a direct current power line by modulating the current on that direct current power line. One method of modulating the current is by placing an inductor on the power line and then using a controlled transistor that turns on and turns off. The inductor will ensure that current keeps flowing but the transistor will induce changes in the current pattern. The excess current from when transistor is turned off must be diverted. Furthermore, to create symmetrical current changes, the inductor should be reverse biased. Thus, a circuit is created that sinks the excess current from when the transistor is turned off and used to reverse bias the inductor.
    Type: Grant
    Filed: May 8, 2012
    Date of Patent: May 6, 2014
    Assignee: Neofocal Systems, Inc.
    Inventors: Mark Peting, Dale Beyer, Tsutomu Shimomura
  • Publication number: 20140111180
    Abstract: Systems and methods are provided for power control. In some implementations, a power control system includes a first transistor having a drain coupled to a first conductor (e.g., first pair of wires of an Ethernet cable), a second transistor having a drain coupled to a second conductor (e.g., second pair of wires of the Ethernet cable), a current sensor coupled to sources of the first and second transistors, and a current management circuit. The current management circuit may detect drain voltages of the first transistor and the second transistor, and adjust gate voltages of the first transistor and the second transistor to keep the drain voltages of the first transistor and the second transistor approximately equal. The current management circuit may detect a current through the current sensor, and adjust the gate voltages of the first transistor and the second transistor to limit the detected current to a current limit.
    Type: Application
    Filed: October 23, 2012
    Publication date: April 24, 2014
    Applicant: Broadcom Corporation
    Inventors: Marius VLADAN, Sesha Panguluri
  • Publication number: 20140111179
    Abstract: A DC-DC converter includes a first differential voltage sensor to detect a first inductor current by sensing a first differential voltage across a first power stage of the DC-DC converter. A second differential voltage sensor detects a second inductor current by sensing a second differential voltage across a second power stage of the DC-DC converter. An integrator stage combines the first differential voltage from the first power stage and the second differential voltage from the second power stage to generate a compensation signal to adjust current balancing for the DC-DC converter.
    Type: Application
    Filed: October 23, 2012
    Publication date: April 24, 2014
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: MICHAEL COULEUR, STEFAN HERZER, NICOLA FLORIO
  • Publication number: 20140097823
    Abstract: Circuits and related methods for artificial ramp generation for pulse-width modulators (PWM) for current control mode switch mode power supplies (SMPS).are disclosed. The artificial ramp generation is separated from a current sensing part and allows easy trimming of both paths. Artificial ramp is generated as a voltage on a capacitor biased by constant current and placed between a voltage sensing node and an input of a PWM comparator. The circuit disclosed reduces circuit complexity and susceptibility to noise and spikes from the input voltage.
    Type: Application
    Filed: October 11, 2012
    Publication date: April 10, 2014
    Applicant: Dialog Semiconductor GmbH
    Inventor: Jindrich Svorc
  • Patent number: 8686707
    Abstract: A voltage regulator with a low quiescent current is provided. The voltage regulator includes a pulse voltage generating unit, a first switch unit, a regulating unit and a power output unit. The pulse voltage generating unit receives an input voltage to provide an intermittent signal with a predetermined period, and output a pulse voltage according to the intermittent signal. The first switch unit is turned on according to the intermittent signal. The regulating unit converts the pulse voltage into a continuous voltage. The power output unit receives the continuous voltage to output a voltage power through a power output terminal. And, the power output unit detects an output current of the power output terminal to adjust current drive capability of the power output unit dynamically. Thus, the pulse voltage generating unit consumes power while the intermittent signal is enabled, so as to achieve the power saving effect.
    Type: Grant
    Filed: November 16, 2011
    Date of Patent: April 1, 2014
    Assignee: SONIX Technology Co., Ltd.
    Inventors: Yu-Pao Kung, Chih-Ping Chen
  • Patent number: 8669753
    Abstract: Provided is a voltage regulator including a phase compensation circuit capable of obtaining an accurate output voltage. The phase compensation circuit includes: a first constant current circuit connected to a gate of an output transistor; a first transistor having a drain connected to the gate of the output transistor; and a second transistor having a drain connected to a gate of the first transistor, a second constant current circuit, and a resistor and having a gate connected to the resistor and any one terminal of a first capacitor, the first capacitor having the other terminal connected to an output terminal of the voltage regulator. This configuration prevents a current from flowing from an output terminal of the differential amplifier circuit to the drain of the first transistor, to thereby reduce an offset voltage to be generated in input transistors of the differential amplifier circuit, thus obtaining an accurate output voltage.
    Type: Grant
    Filed: November 4, 2011
    Date of Patent: March 11, 2014
    Assignee: Seiko Instruments Inc.
    Inventor: Socheat Heng
  • Publication number: 20140068301
    Abstract: To reduce a variation in the electrical characteristics of a transistor. A potential generated by a voltage converter circuit is applied to a back gate of a transistor included in a voltage conversion block. Since the back gate of the transistor is not in a floating state, a current flowing through the back channel can be controlled so as to reduce a variation in the electrical characteristics of the transistor. Further, a transistor with low off-state current is used as the transistor included in the voltage conversion block, whereby storage of the output potential is controlled.
    Type: Application
    Filed: August 29, 2013
    Publication date: March 6, 2014
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Kazunori Watanabe
  • Patent number: 8659275
    Abstract: According to an exemplary embodiment, a III-nitride power conversion circuit includes a gate driver having a plurality of cascaded inverters, each of the plurality of cascaded inverters including at least one III-nitride transistor. At least one of the plurality of cascaded inverters has a cutoff switch and a III-nitride depletion mode load where the cutoff switch is configured to disconnect the III-nitride depletion mode load so as to prevent current from flowing from a supply voltage of the at least one of the plurality of cascaded inverters. The cutoff switch of the at least one of the plurality of cascaded inverters can be driven by one of the plurality of cascaded inverters. The III-nitride power conversion circuit can also include an output driver driven by the gate driver where the output driver has a segmented III-nitride transistor. Furthermore, a selector circuit can be configured to selectively disable at least one segment of the segmented III-nitride transistor.
    Type: Grant
    Filed: March 8, 2011
    Date of Patent: February 25, 2014
    Assignee: International Rectifier Corporation
    Inventor: Tony Bahramian
  • Publication number: 20140049243
    Abstract: A current generator includes an amplifier having a first terminal configured to receive an input voltage, at least one tunable resistor coupled to a second terminal of the amplifier, a resistor calibration circuit coupled to the at least one tunable resistor, and at least one transistor. A gate of the at least one transistor is coupled to an output of the amplifier, and a terminal of the at least one transistor is coupled to the at least one tunable resistor or a load. The resistor calibration circuit is configured to adjust a resistance setting of the at least one tunable resistor to control a current level of the current generator based on a power supply voltage or a current of a reference resistor.
    Type: Application
    Filed: October 29, 2013
    Publication date: February 20, 2014
    Applicant: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.
    Inventors: Ming-Chieh HUANG, Chan-Hong CHERN, Chih-Chang LIN
  • Patent number: 8648580
    Abstract: A regulator for providing a low dropout voltage at an output node of the regulator is provided. An amplifier has a non-inverting input terminal for receiving an input voltage, an inverting input terminal and an output terminal. A first resistor is coupled between a ground and the inverting input terminal of the amplifier. A second resistor is coupled to the inverting input terminal of the amplifier. A first transistor is coupled between a voltage source and the second resistor. A current source coupled between the voltage source and a gate of the first transistor provides a bias current. A second transistor coupled between the first transistor and a current mirror has a gate coupled to the output terminal of the amplifier. The first and second transistors are different type MOS transistors. The replica unit generates the low dropout voltage according to a voltage of the output terminal of the amplifier.
    Type: Grant
    Filed: August 2, 2011
    Date of Patent: February 11, 2014
    Assignee: Mediatek Singapore Pte. Ltd.
    Inventor: KianTiong Wong
  • Publication number: 20140028280
    Abstract: A device, comprising: first and second signal lines; first and second transistors of first conductivity type coupled in series between first and second signal lines and coupled to each other at first node; third and fourth transistors of second conductivity type coupled in series between first and second lines and coupled to each other at second node; power supply node coupled in common to first and second nodes; fifth transistor of first conductivity type coupled between first and second signal lines; and sixth transistor of second conductivity type coupled between first and second signal lines, wherein each of first, second and fifth transistors is configured to receive first control signal at gate electrode thereof, each of the third and fourth transistors is configured to receive second control signal at gate electrode thereof, and sixth transistor is configured to receive third control signal at gate electrode thereof.
    Type: Application
    Filed: July 19, 2013
    Publication date: January 30, 2014
    Applicant: ELPIDA MEMORY, INC.
    Inventor: Yumiko YAMAMOTO
  • Patent number: 8638162
    Abstract: A reference current generating circuit with high current mirror accuracy is provided by low power supply voltage operation. The reference current generating circuit includes a cascode current mirror circuit 1 outputting mirror currents I1 and I2, and a reference current Iref, a current-voltage converter circuit 2 converting the mirror current I1 into a voltage V1, a current-voltage converter circuit 3 converting the mirror current I2 into a voltage V2, a differential amplifier 4 in which the voltage V1 is input to a first input terminal and the voltage V2 is input to a second input terminal, a voltage-current converter circuit 5 converting a voltage V3 output from the differential amplifier 4 into currents I3 and I4, and a current-voltage converter circuit 6 converting the current I3 into a voltage V4 which is output to a gate of a transistor in the cascode current mirror circuit.
    Type: Grant
    Filed: September 23, 2011
    Date of Patent: January 28, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Kazunori Watanabe
  • Publication number: 20140009139
    Abstract: A differential current source includes two source transistors, sources of which are respectively connected to a power source, and a mixer circuit having a first terminal, a second terminal, a third terminal and a fourth terminal, the first terminal and the second terminal being respectively connected to drains of the two source transistors, and the third terminal and the fourth terminal being respectively output terminals, wherein the mixer circuit changes a connection state in accordance with a local signal between a first connection state where the first terminal and the third terminal are connected and also the second terminal and the fourth terminal are connected, and a second connection state where the first terminal and the fourth terminal are connected and also the second terminal and the third terminal are connected.
    Type: Application
    Filed: September 13, 2013
    Publication date: January 9, 2014
    Applicant: FUJITSU LIMITED
    Inventor: Kazuaki OISHI
  • Publication number: 20140009138
    Abstract: A circuit may include an input node configured to receive a signal and an output node configured to be coupled to a load. The circuit may also include a first circuit coupled between the input node and the output node. The first circuit may be configured to receive the signal and to drive the signal on the output node at a first voltage. The circuit may also include an active device coupled to the output node and a second circuit coupled to the active device and the input node. The second circuit may be configured to receive the signal and to drive the signal to the active device at a second voltage that is approximately equal to the first voltage.
    Type: Application
    Filed: July 9, 2012
    Publication date: January 9, 2014
    Applicant: FINISAR CORPORATION
    Inventors: Jason Y. MIAO, Georgios KALOGERAKIS, The'linh NGUYEN
  • Patent number: 8619401
    Abstract: A current source regulator for controlling an output device (Mp) of current source, the output device (Mp) providing an output current (Isrc) to a load. The current source regulator comprises a first feedback loop (1) and second feedback loop (2). The first feedback loop (1) includes a first sensing path to provide a first sensing signal (Is1) for comparison with a first reference to generate a first control signal. The second feedback loop (2) comprises a second sensing path to provide a second sensing signal (Is3, Is3?) for comparison with a second reference (Ib5) to generate a charging current signal (Icharge). The charging current signal (Icharge) is applied to the control signal during a transient state of the current source regulator.
    Type: Grant
    Filed: June 21, 2010
    Date of Patent: December 31, 2013
    Assignee: AMS AG
    Inventor: Pramod Singnurkar
  • Patent number: 8610413
    Abstract: An integrated circuit that includes a power stage and a driver stage, all stages using III-nitride power devices.
    Type: Grant
    Filed: November 18, 2011
    Date of Patent: December 17, 2013
    Assignee: International Rectifier Corporation
    Inventors: Hamid Tony Bahramian, Jason Zhang, Michael A. Briere
  • Patent number: 8604826
    Abstract: A system and method for calibrating bias in a data transmission system including a calibrated bias having impedance calibration for accommodating parameter variations in the data transmission system. A current mirror receives and balances bias currents between the calibrated bias and an output driver from the data transmission system. A digital compensation logic circuit is connected to the calibrated bias to adjust the calibrated bias for variations in parameters causing a current tail effect. A calibration logic circuit adjusts calibration due to variations in operational parameters, such that the tail current variations are minimized.
    Type: Grant
    Filed: December 16, 2011
    Date of Patent: December 10, 2013
    Assignees: Advanced Micro Devices, Inc., ATI Technologies ULC
    Inventors: Junho J. H. Cho, Chihou C. L. Lee
  • Patent number: 8604761
    Abstract: In one embodiment, the current source arrangement comprises a current source (B), that has two output terminals (102, 103) and a control input (101) to be supplied with a control voltage (Vgs) and is set up to provide a current (I) as a function of a voltage (Vds) at the output terminals (102, 103) and the control voltage (Vgs), an operating point adjustment unit (E) that is supplied with an actual value (Vi) proportional to an actual value of the current (I) and is set up to provide the control voltage (Vgs) as a function of the actual value (Vi) and a predetermined target value (Iz) of the current (I), and a comparison unit (A) coupled to the control input (101) of the current source (B) for providing a monitoring signal (100), wherein the monitoring signal (100) is provided as a function of a predetermined limit voltage (VG) and the control voltage (Vgs). A method for operating a current source arrangement is also specified.
    Type: Grant
    Filed: June 1, 2011
    Date of Patent: December 10, 2013
    Assignee: AMS AG
    Inventors: Gilbert Promitzer, Peter Rust, Peter Boesmueller
  • Publication number: 20130307515
    Abstract: The present invention discloses a circuit for generating a dual-mode proportional to absolute temperature (PTAT) current. The circuit includes a voltage stabilizing circuit to provide a voltage reference, and a load current control circuit comprising a first transistor to provide a first load current based on the voltage reference, a second transistor to provide a second load current based on the voltage reference, a first switch to control whether to allow the first load current to flow therethrough in response to different predetermined temperatures, and a second switch to control whether to allow the second load current to flow therethrough in response to the different predetermined temperatures. A resultant current resulting from at least one of the first load current or the second load current has different current magnitudes at the different predetermined temperatures.
    Type: Application
    Filed: May 21, 2012
    Publication date: November 21, 2013
    Applicant: ELITE SEMICONDUCTOR MEMORY TECHNOLOGY INC.
    Inventor: Ming-Sheng Tung
  • Publication number: 20130307514
    Abstract: An I/O circuit for use with an industrial controller provides a photovoltaic optical isolator communicating between a controller and a field-side of the I/O circuit, the photovoltaic optical isolator eliminating the need for high wattage power dropping circuits for powering the field-side of the I/O circuit from high-voltage field signals. The field effect transistor type transistors permit use of the low-power photovoltaic optical isolator while allowing flexible connections to various field circuit types.
    Type: Application
    Filed: May 17, 2012
    Publication date: November 21, 2013
    Inventors: John O'Connell, Dale Terdan, David A. Pasela, Charmaine J. Van Minnen, Bret S. Hildebran
  • Patent number: 8581659
    Abstract: Current sources, systems including the current source, and methods for regulating and/or controlling a circuit using the current source. The current source is generally configured to (i) receive a reference current, a bias voltage and a feedback/input current and (ii) provide an output current. The systems generally include the current source, a circuit directly or indirectly receiving the output current, a bias source/generator configured to provide the bias voltage, and a current reference configured to sink or source a predetermined amount of current from or to the output current. The method generally includes (a) applying a bias voltage to the current source, the current source receiving an input current and providing an output current; (b) sinking or sourcing a reference current from or to the output current; (c) applying the output of the current source directly or indirectly to a regulated circuit; and (d) providing the input current from the regulated circuit.
    Type: Grant
    Filed: January 25, 2010
    Date of Patent: November 12, 2013
    Assignee: Dongbu Hitek Co., Ltd.
    Inventors: Steven Ulbrich, Kenneth Kwok, Jan Krellner, Joon Park
  • Patent number: 8570098
    Abstract: A voltage reducing circuit includes an internal power supply section configured to reduce an external power supply voltage supplied from an external power supply to an internal power supply voltage which is lower than the external power supply voltage based on a reference voltage. A first current control section is configured to control a current flowing through the internal power supply section when the internal power supply voltage is lower than a setting voltage. A second current control section is configured to control the current flowing through the internal power supply section when the internal power supply voltage exceeds the setting voltage.
    Type: Grant
    Filed: August 8, 2012
    Date of Patent: October 29, 2013
    Assignee: Renesas Electronics Corporation
    Inventor: Toshikatsu Jinbo
  • Patent number: 8564274
    Abstract: An improved reference voltage (Vref) generator useable, for example, in sensing data on single-ended channels is disclosed. The Vref generator can be placed on the integrated circuit containing the receivers, or may be placed off chip. In one embodiment, the Vref generator comprises an adjustable-resistance voltage divider in combination with a current source. The voltage divider is referenced to I/O power supplies Vddq and Vssq, with Vref being generated at a node intervening between the adjustable resistances of the voltage divider. The current source injects a current into the Vref node and into a non-varying Thevenin equivalent resistance formed of the same resistors used in the voltage divider. So constructed, the voltage generated equals the sum of two terms: a first term comprising the slope between Vref and Vddq, and a second term comprising a Vref offset.
    Type: Grant
    Filed: January 24, 2009
    Date of Patent: October 22, 2013
    Assignee: Micron Technology, Inc.
    Inventors: Dragos Dimitriu, Timothy M. Hollis
  • Patent number: 8552698
    Abstract: A voltage regulator circuit comprising a first circuit functioning as a voltage dependent resistor, the first circuit having an input coupled to a voltage source and an output and having a resistance dependent on the voltage applied across the circuit by the voltage source such that the resistance increases as the applied voltage increases; and a regulator coupled to the output of the first circuit for providing a regulated output voltage.
    Type: Grant
    Filed: February 28, 2008
    Date of Patent: October 8, 2013
    Assignee: International Rectifier Corporation
    Inventor: Melvin Kit Ho Chow
  • Publication number: 20130249428
    Abstract: A two-wire load control device (such as, a dimmer switch) is operable to control the amount of power delivered from an AC power source to an electrical load (such as, a high-efficiency lighting load) and has substantially no minimum load requirement. The dimmer switch includes a bidirectional semiconductor switch, which is operable to be rendered conductive each half-cycle and to remain conductive independent of the magnitude of a load current conducted through semiconductor switch. The dimmer switch comprises a control circuit that conducts a control current through the load in order to generate a gate drive signal for rendering the bidirectional semiconductor switch conductive and non-conductive each half-cycle. The control circuit may provide a constant gate drive to the bidirectional semiconductor switch after the bidirectional semiconductor switch is rendered conductive each half-cycle.
    Type: Application
    Filed: May 15, 2013
    Publication date: September 26, 2013
    Applicant: Lutron Electronics Co., Inc.
    Inventors: Robert C. Newman, JR., Christopher J. Salvestrini
  • Publication number: 20130249524
    Abstract: This document discusses, among other things, voltage converters and computed on-time voltage converters. In an example, an on-time generator for a voltage converter can include a timing capacitor configured to provide a timing voltage, a comparator configured to receive the timing voltage and a threshold voltage and to provide the timing signal using a comparison of the timing voltage and the threshold voltage, a current source configured to discharge the timing voltage of the timing capacitor after a start-up delay, and first and second compensation capacitors configured to bias the timing voltage of the timing capacitor to compensate for the start-up delay.
    Type: Application
    Filed: March 14, 2013
    Publication date: September 26, 2013
    Applicant: Fairchild Semiconductor Corporation
    Inventors: Juha-Matti Kujala, Jouni MiKa Kalervo Vuorinen
  • Patent number: 8536852
    Abstract: A current balance circuit includes a first and a second current sensors, an averager, a first and a second control modules, and a first and a second rheostat elements. The first and second current sensors receive a first current and a second current from a power source respectively and convert the first and second currents into a first and a second voltages. The averager receives the first and second voltages and calculates to obtain an average voltage. The first and second control modules receive the first voltage, the second voltage, and the average voltage, to obtain a first and a second control signals, to control current conduction ability of the first and second rheostat elements, to make the first and second currents keep a dynamic balance.
    Type: Grant
    Filed: March 23, 2010
    Date of Patent: September 17, 2013
    Assignee: Hon Hai Precision Industry Co., Ltd.
    Inventors: Tsung-Sheng Huang, Chun-Jen Chen, Duen-Yi Ho
  • Publication number: 20130234617
    Abstract: A current control system, and method for controlling current, and a lighting system including the same, are provided. The current control system includes front end circuitry to receive an input voltage and provide a regulated DC voltage to current source circuitry via a first input voltage terminal. Dimming interface circuitry provides a pulse width modulation signal to conversion circuitry, which uses the pulse width modulation signal to generate an analog voltage. The conversion circuitry sends the analog voltage to the current source circuitry via a second input voltage terminal. The current source circuitry uses the regulated DC voltage and the analog voltage to create an output current. The output current drives a load, which, in the lighting system, is one or more solid state light sources.
    Type: Application
    Filed: March 12, 2012
    Publication date: September 12, 2013
    Applicant: OSRAM SYLVANIA INC.
    Inventors: Ankit Sanghvi, Biju Antony, Carlos Becerra
  • Publication number: 20130229166
    Abstract: An apparatus is configured to provide a voltage rising at the output with a programmable slew rate. The apparatus comprises a ramp-up control circuit module for supplying an increasing output voltage that is output to a load circuit. The ramp-up control circuit comprises an amplifier that receives the output of a plurality of selectable mirrored current sources that build up voltage across a capacitor for programming a selected linear slew rate for the increasing output voltage. The apparatus further comprises a glitch filter circuit for stabilizing the increasing output voltage so as to minimize glitches, including current and voltage stress, in the output voltage.
    Type: Application
    Filed: March 1, 2012
    Publication date: September 5, 2013
    Applicant: SANDISK TECHNOLOGIES INC.
    Inventors: Alexander TETELBAUM, Tomer Shaul ELRAN
  • Publication number: 20130221943
    Abstract: A system includes a constant input current filter configured to draw a constant input current from a power source and to generate a variable output current. The constant input current filter includes a capacitor, a boost converter, and a buck converter. The boost converter is configured to receive at least a portion of the input current and to charge the capacitor using at least the portion of the input current during first time periods associated with operation of a load. The buck converter is configured to discharge the capacitor and to provide an additional current as part of the output current during second time periods associated with operation of the load. The load could represent an electronic device having a time-varying output power characteristic, such as a wireless radio.
    Type: Application
    Filed: February 27, 2012
    Publication date: August 29, 2013
    Applicant: Raytheon Company
    Inventors: Everett E. Baker, Bashirul A. Polash, Christopher D. Ballard
  • Publication number: 20130193948
    Abstract: A power circuit for reducing a leakage power using a negative voltage is provided. The power circuit includes a current source including a transistor including a gate. The power circuit further includes a current source control circuit connected to the gate of the transistor, and configured to apply a positive voltage to the gate of the transistor if the current source is to operate in an active mode, and apply the negative voltage to the gate of the transistor if the current source is to operate in an inactive mode.
    Type: Application
    Filed: November 17, 2012
    Publication date: August 1, 2013
    Inventors: Jae Sup LEE, Seong Joong KIM, Bum Man KIM, Han-Kyu LEE, Dae-Chul JEONG, Tae Young CHUNG
  • Patent number: 8497671
    Abstract: The load driving device disclosed in the specification includes a controller to generate a first control signal based on an input signal, a first output transistor to supply an output current to a load according to the first control signal, a first dividing circuit to output a first divided voltage by dividing a voltage across a first primary electrode and a second primary electrode of the first output transistor by a first transistor and a second transistor connected in serial, a first voltage generating circuit to output a first reference voltage, and a first comparator to supply a first over current detection signal to the controller based on the first reference voltage and the first divided voltage.
    Type: Grant
    Filed: June 7, 2011
    Date of Patent: July 30, 2013
    Assignee: Rohm Co., Ltd.
    Inventor: Ryosuke Kanemitsu
  • Patent number: 8482817
    Abstract: An image reading apparatus capable of reading documents includes a reading unit including a light emitting element, a mechanism configured to move the reading unit, and a control unit configured to control the reading unit and the mechanism both to carry out reading by turning on the light emitting element and moving the reading unit and to temporarily stop moving the reading unit upon occurrence of a predetermined factor. The control unit sets a first current value which is caused to flow through the light emitting element when reading is carried out and sets a second current value which is less than the first current value and which is caused to flow through the light emitting element when the reading unit is temporarily stopped.
    Type: Grant
    Filed: April 23, 2010
    Date of Patent: July 9, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Kubozono, Yasuyuki Shinada
  • Publication number: 20130170311
    Abstract: The present invention discloses a power supply. The power supply may comprise an input power terminal, a capacitor module, a first converter module and a second converter module. The first converter module may have a first terminal and a second terminal, wherein the first terminal is coupled to the input power terminal and the second terminal is coupled to the capacitor module. The second converter module may comprise an input and an output, wherein the input of the second converter module is coupled to the input power terminal, and the output of the second converter module is configured to supply a load.
    Type: Application
    Filed: December 28, 2011
    Publication date: July 4, 2013
    Inventors: Pengjie Lai, Jian Jiang
  • Publication number: 20130169177
    Abstract: The present invention discloses an active bleeder circuit capable of triggering a tri-electrode AC switch (TRIAC) circuit in all phase. The active bleeder circuit receives a rectified signal having an OFF phase and an ON phase. The active bleeder includes: a detection circuit for generating a detection signal according to the rectified signal and accumulating the detection signal in the OFF phase of the rectified signal; and a current sinker circuit coupled to the detection circuit, for generates a latching current to trigger the TRIAC circuit by operating a switch when the detection signal exceeds a predetermined level. The present invention also discloses a light emitting device power supply circuit and a TRIAC control method using the active bleeder circuit.
    Type: Application
    Filed: December 27, 2012
    Publication date: July 4, 2013
    Applicant: Richtek Technology Corporation
    Inventors: Chia-Wei Liao, Leng-Nien Hsin, Pei-Yuan Chen, Roland Van Roy, Jing-Meng Liu
  • Patent number: 8471548
    Abstract: A power supply circuit includes an output driver transistor, a buffer circuit, and an error amplification circuit. The buffer circuit includes a first transistor connected to an output terminal and a second transistor functioning as a load for the first transistor. The error amplification circuit includes a differential pair including a first pair of transistors, a current mirror circuit including a second pair of transistors, a constant current source supplying a current and driving the differential pair and the current mirror circuit, a third transistor connected between one of the differential pair and the current mirror circuit. The first and second transistor have the same polarity as the transistors constituting the current mirror circuit, and control terminals of the first and third transistors are connected at a first junction node that is connected to a second junction node between the one of the differential pair and the third transistor.
    Type: Grant
    Filed: October 15, 2010
    Date of Patent: June 25, 2013
    Assignee: Ricoh Company, Ltd.
    Inventor: Ippei Noda
  • Publication number: 20130154603
    Abstract: A Maintain Power Signature (MPS) Powered Device (PD) is described. In one or more implementations, the MPS device comprises a current sensor configured to sense current flowing from Power Sourcing Equipment (PSE) to the PD. The current sense based MPS device also comprises a current generator configured to sink electrical current to prevent the PSE from removing power to the PD. Thus, the electrical current comprises a current amplitude characteristic selected based upon MPS requirements of the PSE. In some implementations, the current is sunk to a ground. In other implementations, the current is sunk to a storage device, such as a storage device included with the PD and/or external to the PD.
    Type: Application
    Filed: December 19, 2012
    Publication date: June 20, 2013
    Applicant: MAXIM INTEGRATED PRODUCTS, INC.
    Inventor: Maxim Integrated Products, Inc.
  • Publication number: 20130155787
    Abstract: A digital voltage boost circuit, optionally working in parallel with an analog voltage regulator, periodically injects a constant amount of current each cycle into the bit line of a high density memory array to eliminate the bias voltage reduction which would otherwise occur. This results in a much faster recovery time and reduces the semiconductor real estate required. A pulse generator in the boost circuit generates one or more current modulation signals which control corresponding current supply devices in a current source. The boost circuit drives a constant amount of current to the bias voltage node each memory cycle.
    Type: Application
    Filed: December 15, 2011
    Publication date: June 20, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: James W. Dawson, Noam Jungmann, Elazar Kachir, Udi Nir, Donald W. Plass
  • Patent number: 8466666
    Abstract: A multi-stage voltage regulating circuit and method with automatic temperature compensation comprises a plurality of charge-pumps, a temperature compensator, a comparative unit and a control logic circuit; wherein, the temperature compensator detects the ambient temperature and outputs a reference voltage related to the ambient temperature, the comparative unit compares the voltage of the output power source to the reference voltage output by the temperature compensator and outputs a comparative signal based on the comparison, and the control logic circuit controls the charging/discharging operations of the charge-pumps based on the comparative signal and voltages of input power sources connected to said charge-pumps to automatically regulate the voltage of the output power source.
    Type: Grant
    Filed: April 5, 2011
    Date of Patent: June 18, 2013
    Assignee: Richtek Technology Corp.
    Inventors: Der-Jiunn Wang, Kuo-Chen Tsai
  • Patent number: 8461913
    Abstract: An integrated circuit comprising an adjustable voltage source to allow a plurality of voltage values to be selected; means for measuring a voltage value derived from the adjustable voltage source; and means for configuring the adjustable voltage source to provide a selected voltage value, wherein the selected voltage value is selected based upon a voltage value measured by the means for measuring and a voltage selected by a controller.
    Type: Grant
    Filed: September 21, 2005
    Date of Patent: June 11, 2013
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Michael Garrard, Daniel Ziegler
  • Publication number: 20130141006
    Abstract: A device includes a positive power supply voltage node; and a first operational amplifier including a first input, a second input, and an output coupled to the second input. The device further includes a first resistor coupled between the second input of the first operational amplifier and the positive power supply voltage node; a second resistor coupled between the output of the first operational amplifier and an electrical ground, and is configured to receive a same current flowing through the first resistor; a second operational amplifier including a first input coupled to the second resistor, and an output coupled to an output node; and a third resistor coupled between the electrical ground and a second input of the second operational amplifier.
    Type: Application
    Filed: November 18, 2011
    Publication date: June 6, 2013
    Applicant: STMicroelectronics, Inc.
    Inventor: Wei Song
  • Patent number: 8456235
    Abstract: The present invention is contrived to adopt a differential pair type amplifier circuit comprising a differential pair constituted by a first transistor receiving an input of a first signal and by a second transistor receiving an input of a third signal generated by outputting a second signal of which the voltage level is a power supply voltage. Elements requiring a matching are two transistors constituting the differential pair for the amplifier circuit. Because of this, the elements requiring a matching can be placed close to each other regardless of a layout between the amplifier circuits.
    Type: Grant
    Filed: August 4, 2009
    Date of Patent: June 4, 2013
    Assignee: Fujitsu Semiconductor Limited
    Inventors: Suguru Tachibana, Kenta Aruga, Tatsuo Kato
  • Patent number: 8456224
    Abstract: By maintaining a substantially constant total die power during the entire lifetime of sophisticated integrated circuits, the performance degradation may be reduced. Consequently, greatly reduced guard bands for parts classification may be used compared to conventional strategies in which significant performance degradation may occur when the integrated circuits are operated on the basis of a constant supply voltage.
    Type: Grant
    Filed: October 13, 2009
    Date of Patent: June 4, 2013
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Maciej Wiatr, Richard Heller, Rolf Geilenkeuser
  • Publication number: 20130127437
    Abstract: A system includes a capacitor and a current source configured to draw a constant input current from a power source and to generate an output current. The current source includes an n-type field effect transistor that is biased to operate as a constant current source. The current source is configured to provide the output current to the capacitor and charge the capacitor during a first time period associated with operation of a load. The current source is also configured to provide the output current to the load and the capacitor is configured to provide an additional current to the load during a second time period associated with operation of the load. The load could represent an electronic device having a time-varying output power characteristic, such as a wireless radio.
    Type: Application
    Filed: November 22, 2011
    Publication date: May 23, 2013
    Applicant: Raytheon Company
    Inventors: Everett E. Baker, Bashirul A. Polash, Christopher D. Ballard