Linearly Acting Patents (Class 323/273)
  • Patent number: 7425812
    Abstract: A fan controller may be integrated in silicon and may use an embedded microcontroller to implement a digital fan control algorithm. The microcontroller may continually monitor temperature and sample the speed of the controlled fan. The speed of the fan may be compared to RPM values fitted on a desired curve that is representative of the Temperature-versus-RPM function for the controlled fan. The fan control algorithm may be based on a ramp-rate closed-loop controller (RRCC), which may be operated to drive the fan to the desired speed at different rates, depending on the difference between the desired RPM and the actual RPM of the fan. The fan may also provide a Fan ID feedback signal to the microcontroller, which may use the Fan ID feedback signal upon system start-up to initialize the RRCC range settings and select the appropriate Temperature-versus-RPM function curve based on pre-determined values for the given fan.
    Type: Grant
    Filed: January 30, 2006
    Date of Patent: September 16, 2008
    Assignee: Standard Microsystems Corporation
    Inventor: Randy B. Goldberg
  • Publication number: 20080218137
    Abstract: A linear voltage regulator includes a first transistor, a feedback circuit, and a control circuit. The first transistor includes a first terminal coupled to an input terminal of the regulator, a second terminal coupled to an output terminal of the regulator, and a control terminal. The first transistor is configured to provide a load current to the output terminal at a desired voltage level based on a control signal on the control terminal. The feedback circuit is coupled to the output terminal and is configured to generate a feedback signal based on an actual voltage level at the output terminal. The control circuit is configured to provide, based on the feedback signal, the control signal at a level to substantially maintain an output voltage at the output terminal at the desired voltage level. An operating current of the control circuit is configured to increase, by a limited amount, responsive to a transient increase in the load current.
    Type: Application
    Filed: March 6, 2007
    Publication date: September 11, 2008
    Inventors: Fabio Hideki Okuyama, Andre Luis Do Couto
  • Publication number: 20080211469
    Abstract: A step-down circuit generates a second power supply lower than a first power supply. The step-down circuit includes an output terminal connected to a load circuit, an output transistor connected between the first power supply and the output terminal, and having a gate terminal connected to a first node, a monitor transistor connected between the first power supply and a second node, and having a gate terminal connected to the first node, and a feedback circuit which sets a gate voltage of the output transistor in accordance with a difference between a voltage obtained by dividing a voltage of the second node and a reference voltage. A size of the monitor transistor is changed in accordance with an operation mode of the load circuit.
    Type: Application
    Filed: January 9, 2008
    Publication date: September 4, 2008
    Inventors: Yasuhiro SUEMATSU, Katsumi Abe
  • Publication number: 20080211470
    Abstract: The present invention discloses an auto discharge linear regulator comprising: a basic linear regulator for converting an input voltage to an output voltage at an output node; a load detector circuit for detecting the load condition at the output node; and an discharge control circuit under control by the load detector circuit for discharging the voltage at the output node.
    Type: Application
    Filed: February 13, 2008
    Publication date: September 4, 2008
    Inventors: Tzu-Huan Chiu, Kwan-Jen Chu, Chien-Ping Lu
  • Patent number: 7414458
    Abstract: A power gating circuit of a signal processing system includes a low dropout linear regulator, a control circuit, and an output circuit. The low dropout linear regulator includes a first transistor, an operational amplifier, a first resistor, a second resistor, and an output end. The output circuit includes a fourth transistor and a step-down circuit. The control circuit controls output voltage of the output circuit according to a control signal.
    Type: Grant
    Filed: March 8, 2006
    Date of Patent: August 19, 2008
    Assignee: Faraday Technology Corp.
    Inventors: Jeng-Huang Wu, Yi-Hwa Chang, Shang-Chih Hsieh
  • Publication number: 20080191671
    Abstract: A regulator circuit for efficiently and accurately outputting a target voltage with a simple circuit configuration. The regulator circuit includes an output circuit, a comparator, a counter block, a latch block, and a decoder block. When the target voltage is applied to an output terminal of the output circuit, the output circuit supplies the comparator with feedback voltage. Further, the feedback signal is provided to the counter block. The counter block performs counting in correspondence with the feedback signal. The latch block holds the signal acquired from the counter block and provides the held signal to the decoder block. The decoder block supplies the comparator with reference voltage. The comparator compares the reference voltage and the feedback voltage and controls the counting.
    Type: Application
    Filed: January 30, 2008
    Publication date: August 14, 2008
    Applicant: FREESCALE SEMICONDUCTOR, INC.
    Inventor: Eiji SHIKATA
  • Publication number: 20080191670
    Abstract: A voltage regulator for providing a voltage regulated output to a load comprises a first loop and a second loop. The first loop comprises a first active device coupled to a first pass device and configured to provide a first, relatively high current output to the load. The second loop comprises a second active device coupled to a second pass device and configured to provide a second, relatively low current output to the load. In this manner, when the inventive concept is applied to low drop-out regulators, the provision of two independent loops reduces dramatically the quiescent current provided by the voltage regulator under low load conditions.
    Type: Application
    Filed: July 21, 2005
    Publication date: August 14, 2008
    Applicant: Freescale Semiconductor, Inc.
    Inventors: Ludovic Oddoart, Gerhard Trauth
  • Patent number: 7411375
    Abstract: An apparatus for issuance of at least one electrical output signal (Iout), wherein the desired electrical current level of the output signal (Iout) is predeterminable, including: at least one measuring resistor, at which the electrical current level of the output signal (Iout) is measurable; at least one adjuster, via which the electrical current level of the output signal (Iout) is settable; and at least one controller, which compares the electrical current level of the output signal (Iout) measured at the measuring resistor with the electrical current level desired for the output signal (Iout), and which controls the electrical current level of the output signal (Iout) via the adjuster; wherein the controller and the measuring resistor are connected with an electric base-potential (VGND); and wherein the base-potential (VGND) is a reference potential for the controller.
    Type: Grant
    Filed: April 20, 2006
    Date of Patent: August 12, 2008
    Assignee: Endress + Hauser Wetzer GmbH + Co. KG
    Inventors: Stephan Konrad, Thomas Haerle, Christian Schneid
  • Publication number: 20080180073
    Abstract: The present invention discloses a power supply comprising: a switching regulator circuit converting an input voltage to an intermediate voltage; a low dropout linear regulator circuit converting the intermediate voltage to an output voltage so as to supply a load current to a load; and a feedback control circuit which increases the noise filtering effect of the low dropout linear regulator circuit when the load current increases.
    Type: Application
    Filed: January 10, 2008
    Publication date: July 31, 2008
    Inventors: Jing-Meng Liu, Chung-Lung Pai, Wei-Che Chiu
  • Patent number: 7405546
    Abstract: A voltage regulator circuit has a first amplifier stage with input and output terminals, a feedback terminal, a pole-inducing transistor, and a compensating network coupled to the output terminal. A second amplifier stage has an input coupled to the first amplifier output, first and second current mirrors, and a pass transistor.
    Type: Grant
    Filed: April 29, 2005
    Date of Patent: July 29, 2008
    Assignee: Atmel Corporation
    Inventors: Hafid Amrani, Hubert Cordonnier, Xavier Rabeyrin
  • Publication number: 20080174288
    Abstract: There is disclosed a regulator for a charge pump having an input signal and generating an output signal at a value greater than the input signal. The charge pump comprises at least a capacitor and at least a device for charging and discharging the capacitor; the regulator comprises means having at the input said signal exiting the charge pump and a reference signal. Said means are able to generate a supply signal for said at least a device in response to the value of the difference between the output signal of the charge pump and said reference signal.
    Type: Application
    Filed: December 28, 2007
    Publication date: July 24, 2008
    Applicant: STMICROELECTRONICS, S.R.L
    Inventors: Marco Poles, Marco Pasotti
  • Publication number: 20080169794
    Abstract: A system for providing a desired substantially constant resistance includes a first transistor interconnected between a first node and a second node. The system also includes a second transistor, the second transistor being diode connected, the first transistor and the second transistor forming a current mirror. A voltage divider is coupled to provide a portion of a voltage associated with the first transistor to the second transistor, the voltage divider being configured parallel to the first transistor to provide a substantially constant resistance between the first node and the second node. A current source is coupled to the second transistor, the current source being controlled to draw an amount of current through the second transistor to set the substantially constant resistance substantially equal to the desired substantially constant resistance.
    Type: Application
    Filed: January 12, 2007
    Publication date: July 17, 2008
    Inventors: Vijaya B. Rentala, Baher Haroun
  • Patent number: 7397227
    Abstract: A low-noise voltage regulator circuit with quick disablement includes an amplifier for outputting a driving voltage according to a reference voltage, a feedback voltage on a feedback node, and an enable signal; an output transistor coupled among the amplifier, an output node, and a first voltage source for outputting an output voltage at the output node; a first discharge transistor having a first size and coupled among the enable signal, the output node, and the feedback node; and a second discharge transistor having a second size being different than the first size and coupled among the enable signal, the feedback node, and a second voltage source; wherein when the enable signal disables the amplifier, the enable signal turns on the first discharge transistor and the second discharge transistor such that the output voltage is quickly pulled down to close a level provided by the second voltage source.
    Type: Grant
    Filed: May 17, 2006
    Date of Patent: July 8, 2008
    Assignee: MediaTek Inc.
    Inventors: Ling-Wei Ke, Chi-Kun Chiu
  • Patent number: 7397226
    Abstract: A circuit and method for providing voltage regulation that operates with relatively low noise, low power, fast start up and low dropout. The invention includes a constant voltage reference that is coupled to a reference amplifier which amplifies the reference voltage to a selectable level. The output of the reference amplifier is provided to an integrated low pass noise filter which suppresses at least the noise generated by the constant voltage reference and the reference amplifier. The output of the integrated noise filter is provided to the inverting input of an error amplifier, whose non-inverting input is coupled to the output voltage (VOUT). Also, the output of the error amplifier is coupled to a gate of a pass transistor that is coupled between the input voltage (VIN) and the output voltage (VOUT) of the invention.
    Type: Grant
    Filed: January 13, 2005
    Date of Patent: July 8, 2008
    Assignee: National Semiconductor Corporation
    Inventors: Vello Mannama, Rein Sabolotny, Viktor Strik, Rein Tiikmaa
  • Patent number: 7394306
    Abstract: A regulator circuit having a voltage output terminal is provided. The regulator circuit includes a current mirror module, a plurality of source followers, and a switch. The current module receives a driving voltage, and has a first current terminal coupled to a driving current and a plurality of second current terminals, so that the driving current is copied to each second current terminal. Furthermore, each of second current terminals is coupled to one of source followers respectively. An output terminal of each source follower is coupled to an input terminal of next source, and the input terminal of the first source follower receives a control voltage. So that the source followers can determine whether the switch conducts the driving voltage to the voltage output terminal or not according to the copied driving current and the control voltage.
    Type: Grant
    Filed: June 16, 2006
    Date of Patent: July 1, 2008
    Assignee: eMemory Technology Inc.
    Inventor: Yin-Chang Chen
  • Publication number: 20080150501
    Abstract: Constant voltage regulator includes an output terminal, an output transistor, an output voltage controller, and a switching circuit. The output terminal outputs a first voltage to an external host apparatus. The output transistor outputs a current in accordance with a signal. The output voltage controller amplifies a difference between a reference voltage and a feedback voltage produced in proportion to the first voltage, and outputs the amplified voltage to the control gate of the output transistor. The switching circuit selectively outputs one of a second voltage greater than the first voltage and a third voltage greater than the second voltage to a substrate gate of the output transistor in response to an operation mode switchable between a first mode in which an output current to the external host apparatus is smaller than a predetermined value and a second mode in which the output current is greater than the predetermined value.
    Type: Application
    Filed: February 22, 2008
    Publication date: June 26, 2008
    Inventor: Kohzoh Itoh
  • Publication number: 20080143308
    Abstract: A power circuit and a charge pumping circuit add one control switch of small size to control a power transistor, and save one switch of large area and one capacitor of large area as compared with a conventional power circuit and a conventional charge pumping circuit. The power circuit includes a power processing circuit, a linear voltage-regulating switch, and a capacitor. The linear voltage-regulating switch includes a power transistor and a control switch. The control switch has a first end coupled to a gate of the power transistor and a second end coupled to one of a drain and a source of the power transistor. When the control switch is “on”, the power transistor is “off”. When the control switch is “off”, the voltage on the drain of the power transistor is maintained at a predetermined value by the linear voltage-regulating switch.
    Type: Application
    Filed: October 3, 2007
    Publication date: June 19, 2008
    Applicant: NOVATEK MICROELECTRONICS CORP.
    Inventors: Chih-Yuan Hsieh, Jiunn-Way Miaw
  • Patent number: 7388354
    Abstract: Systems and methods for increasing driver power dissipation efficiency in a low noise current supply utilizing a power supply and a voltage regulator to power an output current regulator. An analog processing circuit adjusts the voltage drop on the voltage regulator, to make it equal with the voltage drop on current regulator.
    Type: Grant
    Filed: April 11, 2005
    Date of Patent: June 17, 2008
    Assignee: Newport Corporation
    Inventor: Adrian S. Nastase
  • Publication number: 20080136385
    Abstract: A power transmission system is described. The power transmission system comprises a local power converter, a dedicated power transmission cable and a regulating unit. The power transmission system couples the local power converter to the KVM circuit of the remote KVM device via the dedicated power transmission cable and the regulating unit. The local power converter converts a first power signal into a second power signal. The dedicated power transmission cable has a first end and a second end. The remote regulating unit is able to regulate the second power signal to generate a third power signal. The first end of the dedicated power transmission cable is coupled to the power converter for receiving the second power signal from the local power converter. The second end of the dedicated power transmission cable is coupled to the remote regulating unit for supplying the regulated second power signal to the remote KVM device.
    Type: Application
    Filed: December 8, 2006
    Publication date: June 12, 2008
    Applicant: Aten International Co., Ltd.
    Inventors: Chih-tao Hsieh, Fu-Chih Shen, Kuan-Lun Chzu
  • Publication number: 20080136384
    Abstract: A voltage regulator circuit for a CAN transceiver has a preregulator circuit which reduces an input voltage to a maximum predetermined voltage. The preregulator circuit is built with diffused MOS (DMOS) or drain extended MOS (DEMOS) transistors or laterally diffused MOS (LDMOS) transistors that are usable with the higher input voltages. A main regulator is coupled to the preregulated voltage to generate the output voltage. The main regulator utilizes lower voltage but faster core transistors and is stable without a load capacitance.
    Type: Application
    Filed: December 6, 2006
    Publication date: June 12, 2008
    Applicant: TEXAS INSTRUMENTS, INCORPORATED
    Inventors: Mohammad A Al-Shyoukh, Kannan Soundarapandian
  • Publication number: 20080129261
    Abstract: A linear voltage regulator is provided having a first transistor connected between a terminal for an input voltage and a terminal for an output voltage, a reference voltage source for producing a reference voltage, a first resistor, a second resistor, a second transistor, wherein the first resistor, the second resistor, and the second transistor are series-connected between the terminal for the output voltage and a reference voltage, and constitute a voltage divider, wherein a divided output voltage is present at a tap of the voltage divider, and also having a differential amplifier with an inverting input and a non-inverting input, wherein the inverting input is connected to the reference voltage source, the non-inverting input is connected to the tap of the voltage divider, and an output terminal of the differential amplifier is connected to a control terminal of the first transistor.
    Type: Application
    Filed: September 5, 2007
    Publication date: June 5, 2008
    Inventor: Reinhard Oelmaier
  • Publication number: 20080122416
    Abstract: An LDO regulator includes two linear regulator circuits and an internal priority logic scheme that favors generating a regulated output voltage using a regulated supply voltage over an unregulated supply voltage. The unregulated supply voltage is applied to a first input terminal from a raw voltage source. The regulated supply voltage is applied to a second input terminal from, for example, a switching (e.g., BUCK) regulator. Two output devices are respectively connected between the first and second input terminals and the LDO output terminal. The first regulator circuit causes the first output device to supply the desired regulated output voltage while the switching regulator ramps up. Once the regulated supply voltage is high enough to allow regulation, the internal priority logic scheme disables the first regulator circuit, whereby the desired regulated output voltage is generated solely by the second regulator circuit through the second output device.
    Type: Application
    Filed: November 6, 2006
    Publication date: May 29, 2008
    Applicant: Micrel, Incorporated
    Inventors: Andrew Cowell, David Wayne Ritter
  • Publication number: 20080116864
    Abstract: A detection resistor is disposed in a main current path in order to detect an output current flowing through an output switching device in a conventional DC-DC converter that converts a DC input voltage into a stepped down DC output voltage by turning on/off of the output switching device. At that time, the detection resistor generates heat that is not negligible. In a DC-DC converter of this invention, a voltage detection circuit is connected in parallel with an output switching device, and the voltage detection circuit is put into operation a predetermined time after the output switching device is turned on. In addition, a detection switching device, which constitutes the voltage detection circuit, is designed to have a higher ON resistance than an ON resistance of the output switching device.
    Type: Application
    Filed: October 24, 2007
    Publication date: May 22, 2008
    Inventors: Yukio Goto, Madoka Nishikawa
  • Patent number: 7375502
    Abstract: A method and a circuit for scrambling the current signature of a load comprising at least one integrated circuit executing digital processings, including supplying at least the integrated circuit from a supply voltage external to the circuit by combining a current provided by a first linear regulator with a current provided by at least one capacitive switched-mode power supply circuit with one or several switched capacitances.
    Type: Grant
    Filed: February 7, 2006
    Date of Patent: May 20, 2008
    Assignees: STMicroelectronics S.A., Universite D.Aix-Marseille I
    Inventors: Alexandre Malherbe, Edith Kussener, Vincent Telandro
  • Publication number: 20080111525
    Abstract: A reference voltage supply circuit includes a first supply circuit that includes a reference-voltage first-type operational amplifier and supplies an analog reference voltage to a first analog reference voltage line, and a second supply circuit that includes a reference-voltage second-type operational amplifier and supplies the analog reference voltage to a second analog reference voltage line. When a channel width and a channel length of a differential-stage transistor of a differential section of the reference-voltage first-type operational amplifier are respectively referred to as W1a and L1a, a bias current flowing through the differential section is referred to as Ia, a channel width and a channel length of a differential-stage transistor of a differential section of the reference-voltage second-type operational amplifier are respectively referred to as W1b and L1b, and a bias current flowing through the differential section is referred to as Ib, W1b×L1b>W1a×L1a and Ia>Ib are satisfied.
    Type: Application
    Filed: November 8, 2007
    Publication date: May 15, 2008
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Akihiro Fukuzawa
  • Publication number: 20080106244
    Abstract: An exemplary DC-DC converting circuit (2) includes an input terminal (20), a regulating circuit (21), a bleeder circuit (23), an output terminal (25), a voltage-controlling terminal (26), and a load (24). The input terminal, the regulating circuit, the bleeder circuit, and the output terminal are connected in series. The output terminal is grounded via the load. The voltage-controlling terminal is configured to supply a controlling voltage that controls the regulating circuit, and the bleeder circuit is configured to supply a stable divided voltage to the output terminal for output.
    Type: Application
    Filed: November 5, 2007
    Publication date: May 8, 2008
    Inventors: Hong-Bo Zhou, Tong Zhou
  • Patent number: 7358709
    Abstract: Constant voltage regulator includes an output terminal, an output transistor, an output voltage controller, and a switching circuit. The output terminal outputs a first voltage to an external host apparatus. The output transistor outputs a current in accordance with a signal. The output voltage controller amplifies a difference between a reference voltage and a feedback voltage produced in proportion to the first voltage, and outputs the amplified voltage to the control gate of the output transistor. The switching circuit selectively outputs one of a second voltage greater than the first voltage and a third voltage greater than the second voltage to a substrate gate of the output transistor in response to an operation mode switchable between a first mode in which an output current to the external host apparatus is smaller than a predetermined value and a second mode in which the output current is greater than the predetermined value.
    Type: Grant
    Filed: January 29, 2007
    Date of Patent: April 15, 2008
    Assignee: Ricoh Company, Ltd.
    Inventor: Kohzoh Itoh
  • Patent number: 7358708
    Abstract: A linear voltage regulator provides a regulated load voltage to a load. In a preferred embodiment, the linear voltage regulator includes: a regulating circuit for receiving an input voltage and providing an output voltage to a load, the regulating circuit being driven by a driving voltage; and two resistors connected to each other in series receiving the output voltage and providing an adjusting current to the regulating circuit. The linear voltage regulator is capable of providing a greater current to the load, and having a wide range of input voltages.
    Type: Grant
    Filed: November 17, 2005
    Date of Patent: April 15, 2008
    Assignees: Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd., Hon Hai Precision Industry Co., Ltd.
    Inventors: Wu Jiang, Yong-Zhao Huang, Yun Li
  • Publication number: 20080067991
    Abstract: The present invention discloses a current generating apparatus for generating an output current. The current generating apparatus includes: a first current mirror; a first bias current generator for providing a first bias current, and the first bias current generator includes: a first current source for providing the first current; and a capacitive device for conducting a reference current; a second current mirror for generating a second mirror current; a second bias current generator for generating a second current; a third current source for providing a third current, wherein the second mirror current is equal to the third current; a feedback circuit; and a fourth current source for providing a fourth current, wherein the output current is outputted at an output node of the first current mirror.
    Type: Application
    Filed: December 6, 2006
    Publication date: March 20, 2008
    Inventors: Chien-Lung Lee, Yi-Wen Huang
  • Patent number: 7342440
    Abstract: The invention relates to a current regulator having the following features: a first semiconductor body (1; 1?) having a first and second terminal contact (11, 12), a transistor (T) having a control terminal and a load path, which is integrated in the semiconductor body (1; 1?) and the load path of which runs between the terminal contacts (11, 12) of the semiconductor body, a current measuring resistor (22), which is at least partly formed by a section of the load path of the transistor, an evaluation and drive circuit (3), which is connected to the current measuring resistor (22) and which is designed to drive the transistor depending on a voltage across the measuring resistor (22).
    Type: Grant
    Filed: March 3, 2006
    Date of Patent: March 11, 2008
    Assignee: Infineon Technologies Austria AG
    Inventors: Emanuele Bodano, Michael Lenz
  • Patent number: 7312598
    Abstract: A low drop out (LDO) regulator that includes a novel error amplifier, which is arranged with a first stage that employs both NMOS and PMOS devices that are similarly doped in differential pairs and a second stage that operates with NMOS and PMOS devices in a push-pull arrangement. In addition to the error amplifier, the LDO regulator can also include a startup circuit coupled to an enable voltage, a reference filter circuit coupled to a reference voltage, an output circuit, a quiescent current control circuit, and a pulse generator circuit. Also, an internal RC network is provided to compensate for phase shift. The integrated operation of the components of the regulator enables stable and fast operation of an LDO regulator with no external capacitors connected to the input or output terminals.
    Type: Grant
    Filed: August 25, 2006
    Date of Patent: December 25, 2007
    Assignee: National Semiconductor Corporation
    Inventor: Shengming Huang
  • Patent number: 7307434
    Abstract: The voltage application probe (54) and the voltage measurement probe (56) are connected to the voltage application pad (74) and the voltage measurement pad (76) of the semiconductor device (70). The voltage application pad (74) and the voltage measurement pad (76) are connected by the conductor (78), measuring the voltage applied to the voltage application pad (74) through the voltage measurement probe (56). The voltage compensation circuit (14) in the voltage development device (10) operates to make the voltage applied to the voltage application pad (74) equal to the set voltage for the voltage development device (10). Even when the resistance between the voltage application probe (54) and the voltage application pad (74) increases, the accurate setting voltage is applied to the voltage application pad (74).
    Type: Grant
    Filed: September 9, 2004
    Date of Patent: December 11, 2007
    Assignee: Oki Electric Industry Co., Ltd
    Inventor: Shinobu Watanabe
  • Publication number: 20070279023
    Abstract: According to one exemplary embodiment, a voltage up-conversion circuit includes a modulated voltage generator circuit, where the modulated voltage generator circuit is configured to receive an input voltage and generate a modulated voltage, and where the modulated voltage generator circuit includes at least one transistor. The voltage up-conversion circuit further includes a switching circuit coupled to the modulated voltage generator circuit, where the switching circuit is configured to couple the modulated voltage to a load capacitor when the modulated voltage is at a high level and decouple the modulated voltage to the load capacitor when the modulated voltage is at a low level. In the voltage up-conversion circuit, the load capacitor reaches a voltage greater a breakdown voltage of the at least one transistor in the modulated voltage generator circuit. The breakdown voltage can be a reliability breakdown voltage.
    Type: Application
    Filed: June 6, 2006
    Publication date: December 6, 2007
    Inventor: Bin Zhao
  • Patent number: 7289308
    Abstract: An overcurrent protection circuit has an output voltage detection resistor for detecting an output voltage. A foldback overcurrent protection circuit detects an output current flowing through an output transistor and controls the output current flowing through the output transistor in accordance with the detected output current. A first logic generating circuit receives an overcurrent detection signal from the foldback overcurrent protection circuit corresponding to the detected output current. A second logic generating circuit receives a detection signal from the output voltage detection resistor corresponding to a decrease in the detected output voltage. An AND circuit receives and processes an overcurrent delay signal generated by the first logic generating circuit and a voltage detection signal generated by the second logic generating circuit.
    Type: Grant
    Filed: November 24, 2004
    Date of Patent: October 30, 2007
    Assignee: Seiko Instruments Inc.
    Inventor: Katsunori Kimura
  • Patent number: 7285940
    Abstract: A voltage regulator configured to receive a supply voltage from a voltage supply and provide a regulated voltage to digital circuitry is provided. The voltage regulator comprises first circuitry configured to inhibit high frequency energy generated by the digital circuitry from transmitting into the voltage supply, second circuitry configured to inhibit low frequency energy generated by the digital circuitry from transmitting into the voltage supply, and third circuitry configured to maintain the regulated voltage at a substantially constant value in response to a current drawn by the digital circuitry.
    Type: Grant
    Filed: September 7, 2005
    Date of Patent: October 23, 2007
    Assignee: NXP B.V.
    Inventors: Donald A. Kerth, Russell Croman, Brian D. Green, Lysander Lim, James Maligeorgos, Xiachuan Guo, Augusto M. Marques
  • Publication number: 20070241728
    Abstract: A low-dropout (LDO) voltage regulator for generating an output voltage is disclosed. The voltage regulator includes a startup circuit, a curvature corrected bandgap circuit, an error amplifier, a metal oxide semiconductor (MOS) pass device and a voltage slew rate efficient transient response boost circuit. The MOS pass device has a gate node which is coupled to the output of the error amplifier, and a drain node for generating the output voltage. The voltage slew rate efficient transient response boost circuit applies a voltage to the gate node of the MOS pass device to accelerate the response time of the error amplifier in enabling the LDO voltage regulator to reach its final regulated output voltage when an output voltage drop occurs in the LDO voltage regulator.
    Type: Application
    Filed: February 20, 2007
    Publication date: October 18, 2007
    Applicant: ATMEL CORPORATION
    Inventor: Frederic Demolli
  • Publication number: 20070216381
    Abstract: A linear regulator circuit for suppressing power supply noise that propagates to an output voltage. An LDO circuit functioning as the linear regulator circuit is provided with an output transistor including a source for receiving input voltage, a drain for outputting the output voltage, and a control terminal. An error amplifier powered by the input voltage generates a control voltage for controlling the output transistor based on a potential difference between a feedback voltage, which corresponds to the output voltage, and a reference voltage. A first capacitor and a resistor are connected in series between the source of the output transistor and an output terminal of the error amplifier.
    Type: Application
    Filed: August 7, 2006
    Publication date: September 20, 2007
    Inventors: Chikara Tsuchiya, Eiji Nishimori
  • Publication number: 20070216382
    Abstract: A compensated regulator includes a transconductance stage having a positive input for receiving a reference voltage, a negative input, and an output, an adjustable compensation block coupled between the output of the transconductance stage and ground, a feedback circuit having a first node coupled to the output of the compensated regulator, a second node coupled to the negative input of the transconductance stage, and a third node coupled to ground, and a driver stage having an input coupled to the output of the transconductance stage, a current output coupled to the output of the compensated regulator, and a sense output coupled to the adjustable compensation block.
    Type: Application
    Filed: March 9, 2007
    Publication date: September 20, 2007
    Applicant: Shenzhen STS Microelectronics Co., Ltd.
    Inventors: DaSong Lin, Gang Zha
  • Patent number: 7262585
    Abstract: A power supply system having a transistor, a linear regulator, a DC-DC converter, and a control circuit. The transistor has an input, a substrate, a first node, and a second node. The first node is operably coupled to a non-battery power source. A linear regulator is operably coupled to the second node to produce a regulated output voltage based on the non-battery power source, when enabled. A DC-DC converter is operably coupled to produce the regulated output voltage based on a battery power source, when enabled. A control circuit is operably coupled to the input node and the substrate of the transistor wherein when the DC-DC converter is enabled, the control circuit controls a reverse leakage current of the transistor, and when the linear regulator is enabled in a zero load-state, the control circuit controls a forward leakage current of the transistor, and when the linear regulator is enabled in a non-zero load-state, the control circuit provides a current limit for the linear regulator.
    Type: Grant
    Filed: May 17, 2005
    Date of Patent: August 28, 2007
    Assignee: Sigmatel, Inc.
    Inventor: Marcus W. May
  • Patent number: 7262583
    Abstract: A regulator system for supplying power to a microelectronic device is disclosed. The system includes an array of a plurality of regulators, where each regulator provides a portion of power required to operate the device. The system may further include an intermediate power regulator that supplies power to the array of regulators.
    Type: Grant
    Filed: December 15, 2003
    Date of Patent: August 28, 2007
    Assignee: Primarion, Inc.
    Inventors: William Pohlman, Michael Eisele
  • Publication number: 20070188154
    Abstract: A linear voltage regulator comprises a transistor for converting a supply voltage to an output voltage. By directly monitoring the supply voltage and thereby rapidly responding when the supply voltage suffers a ripple, the linear voltage regulator enhances the stability of the output voltage.
    Type: Application
    Filed: February 12, 2007
    Publication date: August 16, 2007
    Inventors: Cheng-Hsuan Fan, Chao-Hsuan Chuang, Hung-Che Chou, Ching-Hsiang Yang, Chih-Ping Tan
  • Patent number: 7248025
    Abstract: In a voltage regulator, a reference voltage generating circuit generates a reference voltage. A drive transistor is connected between a first power supply terminal and an output terminal and has a control terminal. A voltage divider generates a feedback voltage which is an intermediate voltage between voltages at the output terminal and a first power supply terminal. A differential amplifier generates an error voltage in accordance with the feedback voltage of the voltage divider and the reference voltage, and transmits it to the control terminal of the drive transistor. An oscillation preventing capacitor is connected between the control of the drive transistor and the output terminal. A capacitor is connected between the first power supply terminal and the first input of the differential amplifier.
    Type: Grant
    Filed: April 29, 2005
    Date of Patent: July 24, 2007
    Assignee: NEC Electronics Corporation
    Inventor: Masahiro Adachi
  • Patent number: 7230408
    Abstract: A PFM-type voltage regulator circuit converts an unregulated input voltage into a regulated output voltage using a first transistor controlled by a pulse control circuit and a second transistor controlled by a linear regulator circuit. The linear regulator circuit controls the second transistor when the regulated output voltage falls to a predetermined minimum target voltage level, thereby maintaining the regulated output voltage at the minimum target voltage level. The pulse control circuit detects the current passing through the second transistor, and in response generates a pulse signal having a predetermined duration that fully turns on the first transistor. The voltage through the first transistor is converted to an increasing inductor current that refreshes the regulated output voltage to a maximum target voltage level. When the pulse signal ends, the regulated output voltage again begins to fall toward the predetermined minimum target voltage level, and the cycle is repeated.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: June 12, 2007
    Assignee: Micrel, Incorporated
    Inventors: Charles L. Vinn, Raymond D. Zinn
  • Patent number: 7227343
    Abstract: A linear voltage regulator provides a selectable output voltage to a load. The linear voltage regulator includes: a regulating circuit including an input terminal for receiving an input voltage, an output terminal for providing an output voltage to a load, and an adjusting terminal; a first resistor and a second resistor connected between the output terminal and ground for receiving the output voltage; and a voltage sampling control circuit electrically connected to a node between the first resistor and the second resistor for receiving logic signals from a controlling chip, and generating a reference current to the adjusting terminal of the regulating circuit to provide the selectable output voltage.
    Type: Grant
    Filed: April 22, 2006
    Date of Patent: June 5, 2007
    Assignees: Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd., Hon Hai Precision Industry Co., Ltd.
    Inventors: Wu Jiang, Yong-Zhao Huang, Yong-Xing You
  • Patent number: 7224156
    Abstract: A voltage regulator includes a first stage capable having a first current flowing through it. A second stage has a second current. A third stage is capable of outputting an output voltage and has a third current flowing through it. The first, second and third currents are proportional to each other throughout a range of operation of the voltage regulator between substantially zero output current and maximum output current. The first stage drives the second stage as a low input impedance load.
    Type: Grant
    Filed: January 19, 2005
    Date of Patent: May 29, 2007
    Assignee: Broadcom Corporation
    Inventor: Chun-Ying Chen
  • Patent number: 7218084
    Abstract: A low dropout voltage (LDO) regulator comprises an output stage (EtS) of the amplifier (AMP), which has a main output and n auxiliary outputs which can respectively deliver a main control voltage (VGPRINC) and n auxiliary control voltages (VG1, . . . , VGn); and a power stage (EtP) which has a main power transistor (PmosPrinc), controlled at its gate by the main control voltage (VGPRINC), and p power modules (module 1, . . . , module n) of identical layout with p less than or equal to n, respectively having p auxiliary power transistors (PMos1, . . . , PMosn) each controlled at their gate by p auxiliary control voltages (VG1, . . . , VGn). The number p is selected as a function of an intended maximum output current.
    Type: Grant
    Filed: July 12, 2005
    Date of Patent: May 15, 2007
    Assignee: STMicroelectronics S.A.
    Inventors: Alexandre Pons, Fabienne Grigis
  • Patent number: 7218083
    Abstract: The present invention is a voltage regulator circuit with enhanced frequency compensation. The voltage regulator includes an error amplifier, a dynamic bias circuit, an enhanced frequency compensation unit, a pass device and a compensation circuit. A signal from the pass device acts as an input signal of the error amplifier and is compared with another input signal, producing a differential signal. The differential signal is amplified and then provided to the dynamic circuit and the enhanced frequency compensation unit. The enhanced frequency compensation unit is provided such that a zero reference value in a left-hand plane can be generated to optimize the compensation for the voltage regulator circuit. The error amplifier includes a capacitor for compensating an output voltage of the voltage regulator circuit.
    Type: Grant
    Filed: May 23, 2005
    Date of Patent: May 15, 2007
    Assignee: O2Mincro, Inc.
    Inventors: Wei Wang, XiaoHu Tang, XiaoHua Hou
  • Patent number: 7218082
    Abstract: A disclosed amplifier and buffer circuit, for example for a linear voltage regulator, comprises an input gain stage, an integrator and a unity-gain output stage. An output stage compensation scheme enables stable operation over a broad range of output capacitance. For low to moderate output capacitance, the design of the output stage effectively pushes the output pole to high frequencies while an internal pole provided by the integrator is dominant and rolls off the gain at lower frequencies. For high output capacitance, an input impedance of the buffer couples the internal pole and output pole, such that the output pole becomes dominant while the internal pole gets pushed to higher frequencies, maintaining stability. This input impedance connection may utilize the base-emitter resistance of a bipolar junction transistor connected to the internal node, or the connection may use an MOS transistor and a separate RC circuit.
    Type: Grant
    Filed: January 21, 2005
    Date of Patent: May 15, 2007
    Assignee: Linear Technology Corporation
    Inventors: William Louis Walter, Joseph Sinohin Panganiban
  • Patent number: 7218168
    Abstract: A voltage regulator and a method for voltage regulation are described. An adjustable driver is coupled to receive an input voltage, a gating voltage, and first control signaling. The adjustable driver includes driver transistors. The adjustable driver is configured to provide a drive current responsive to the gating voltage. The drive current is provided through one or more of the driver transistors at least a portion of which are selectively gated responsive to the first control signaling. A controller is coupled to receive the input voltage and the gating voltage. The controller is configured to provide the first control signaling responsive to the gating voltage. Control circuitry is configured to provide the gating voltage responsive to load current.
    Type: Grant
    Filed: August 24, 2005
    Date of Patent: May 15, 2007
    Assignee: Xilinx, Inc.
    Inventor: Arifur Rahman
  • Patent number: RE40320
    Abstract: A permanent magnet alternator including a stationary stator including a plurality of spaced stator poles projecting inwardly from the stator, a winding circuit wound through the spaces between the stator poles, a rotor assembly mounted for rotation within the stator, including a plurality of permanent magnets fixedly mounted on an outer circumferential surface of the rotor in alternating polarity, and a retaining shield for reducing the effects of centrifugal motion of the rotor during operation of the alternator.
    Type: Grant
    Filed: March 4, 2005
    Date of Patent: May 20, 2008
    Assignee: E-Tech Corporation
    Inventors: Julius J. Stevens, William C. Edmundson, Ronald E. Murray, Craig G. Young