Patents Examined by Jung Ho Kim
  • Patent number: 6188271
    Abstract: A Norton equivalent implementation of a fail safe bias circuit drives a bus to provide a stable bias voltage which is not affected by an output impedance of a current source. The Norton equivalent implementation has first current source, a bias resistor and a current sink in series. The bias resistor is connected across a pair of differential bus lines so that the current flowing through the bias resistor causes a bias voltage to be generated between the bus lines. The current to the bias resistor is selectively switched on and off to control the bias voltage so that the bias voltage can be turned off during high speed data transfers on the bus.
    Type: Grant
    Filed: July 13, 1998
    Date of Patent: February 13, 2001
    Inventors: Minhui Wang, Dean A. Wallace
  • Patent number: 6188269
    Abstract: The circuits and methods of the present invention provide rail-to-rail output stages that cancel the non-linear components of the transconductances of transistors used in the output stages, that allow the idling current in the output stages to be controlled by external current sources and device size ratios, and that enable the idling current in the output stages to be maintained independently of manufacturing processes, temperature, and power supply voltages. The output stages generally comprise a complementary subcircuit, a current mirror and an output driver. The output stages receive an input signal and a bias voltage from an external source and responsively produce a push current that feeds current into a load and a pull current that pulls current from the load. When the push current matches the pull current, the output stages are said to be “idling.” The bias voltage controls the idling current.
    Type: Grant
    Filed: May 17, 2000
    Date of Patent: February 13, 2001
    Assignee: Linear Technology Corporation
    Inventor: Max Wolff Hauser
  • Patent number: 6184726
    Abstract: Level shifter circuits are used to configure analog or multilevel memory cells. A level shifter circuit generates an output voltage that is above the input voltage by an offset voltage value. The magnitude of this offset voltage or the relationship between the input and output voltages of the level shifter is adjustable or programmably selectable. Adjustments can be made after the integrated circuits is fabricated and packaged. Adjustments are made by configuring bits of data in the integrated circuit to indicate the offset voltage or other parameters. These configuration bits are implemented using latches, flip-flops, registers, memory cells, or other storage circuits.
    Type: Grant
    Filed: June 29, 1999
    Date of Patent: February 6, 2001
    Assignee: SanDisk Corporation
    Inventors: Andreas M. Haeberli, Carl W. Werner, Cheng-Yuan Michael Wang, Hock C. So, Leon Sea Jiunn Wong, Sau C. Wong
  • Patent number: 6184741
    Abstract: A charge pump comprises at least one charge pump stage including a first diode having an anode and a cathode, and a capacitor having a first plate connected to the cathode of the diode and a second plate connected to a clock signal that periodically varies between a reference voltage and a supply voltage, the anode of said diode forming a first terminal of the charge pump. The charge pump further comprises a second diode having an anode connected to the cathode of the first diode and a cathode forming a second terminal of the charge pump, first switching means for selectively coupling the first terminal of the charge pump to the voltage supply and second switching means for selectively coupling the second terminal of the charge pump to the reference voltage.
    Type: Grant
    Filed: July 28, 1997
    Date of Patent: February 6, 2001
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Andrea Ghilardelli, Giovanni Campardo, Jacopo Mulatti
  • Patent number: 6184744
    Abstract: An internal power supply voltage generation circuit includes a main amplifier that supplies a current from an external power supply node to an internal power supply line in accordance with the difference between a reference voltage from a reference voltage generation circuit and an internal power supply voltage on the internal power supply line. The current supply amount by the main amplifier is adjusted by a level adjust circuit, according to the difference between the external power supply voltage and the reference voltage. The internal power supply voltage generation circuit can suppress reduction in the internal power supply voltage in the vicinity of the lower limit area of the differential power supply voltage.
    Type: Grant
    Filed: September 8, 1998
    Date of Patent: February 6, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Fukashi Morishita
  • Patent number: 6181187
    Abstract: A method and circuit for automatically centering the control loop bias current by sensing and “memorizing” the total steady state bias current used by the function block (VGA or VCO) through the use of both digital and analog memory elements. The present invention uses an auto-centering, high-impedance current driver to supply the bias current. This current driver cancels out offset currents by exploiting the high output impedance nature of a CMOS current driver using cascoded or resistor source de-generated FET devices.
    Type: Grant
    Filed: September 30, 1999
    Date of Patent: January 30, 2001
    Assignee: Texas Instruments Incorporated
    Inventors: Christopher J. Daffron, James M. Aralis
  • Patent number: 6181189
    Abstract: The interface circuit of the present invention is composed to provide: changeover switch 24 that switches between a connection state in which pull-up resistor 23 is connected to input terminal 22 and a connection state in which pull-down resistor 23 is so connected; and microcomputer 26 that discriminates whether it is sink input or source input by discriminating the switch connection state of this changeover switch 24. Moreover, the interface circuit is composed to switch between a signal output state that outputs a signal that is an inversion of the input signal and a signal output state that outputs the input signal as it stands, based on the above discrimination result by this microcomputer 26.
    Type: Grant
    Filed: November 25, 1998
    Date of Patent: January 30, 2001
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tamotsu Endo, Youichi Goushi
  • Patent number: 6181191
    Abstract: A dual current source circuit provides dual currents of the same magnitude and having coefficients of temperature compensation that are also equal but opposite. The core of the circuit is a degenerated differential pair of bipolar junction transistors wherein the base of a first transistor of the pair is connected to a bandgap voltage reference. The base of the second transistor of the pair is connected to a PTAT current source having only one of a positive or a negative coefficient of temperature compensation and a resistor which generates a voltage difference between the bases of the two transistors. This voltage difference generates dual currents, each having equal but opposite coefficients of temperature compensation. A temperature independent stable tail current is provided to the transistors and can be generated by summing the current output of a negative PTAT current source and a positive PTAT current source.
    Type: Grant
    Filed: September 1, 1999
    Date of Patent: January 30, 2001
    Assignee: International Business Machines Corporation
    Inventor: Matthew James Paschal
  • Patent number: 6181192
    Abstract: A constant voltage circuit having excellent temperature characteristics at a wide temperature range. Temperature characteristics control means constructed by connecting a voltage dividing circuit formed by connecting fixed resistors in series to a diode in parallel is provided between a fixed resistor and a Zener diode having a positive temperature coefficient of a bridge circuit, and the output of a connection point between the fixed resistors of the temperature characteristics control means is applied to the non-inversion input terminal of a differential amplifier to correct the temperature change of the Zener diode.
    Type: Grant
    Filed: November 17, 1999
    Date of Patent: January 30, 2001
    Assignee: Mitsubishi Denki Kaibushiki Kaisha
    Inventors: Ryuji Tohyama, Naruki Suetake, Minoru Abe
  • Patent number: 6175262
    Abstract: The present invention relates to a booster circuit including a first P-MOS transistor, the source of which is connected to a high voltage line; a second N-MOS transistor, the drain of which is connected to a first supply potential and the source of which is connected to the drain of the first transistor; a first capacitor connected between the gate of the first transistor and a terminal of reception of a first clock signal; a second capacitor connected between the gate of the second transistor and the reception terminal for the first clock signal; a third capacitor connected between the drain of the first transistor and a reception terminal for a second clock signal, complementary to the first clock signal; two precharge diodes the first capacitor from the high voltage line; and one precharge diode for the second capacitor.
    Type: Grant
    Filed: December 31, 1997
    Date of Patent: January 16, 2001
    Assignee: SGS-Thomson Microelectronics S.A.
    Inventors: Laurent Savelli, David Novosel
  • Patent number: 6172555
    Abstract: A bandgap voltage reference circuit wherein a voltage change is induced across one element to compensate for the temperature-induced voltage change across another element. A stable voltage reference is realized across the series combination of the two elements. The circuit includes an operational amplifier, two transistors, a voltage divider and a non-linear temperature-dependent element. The operational amplifier has two input terminals and an output terminal. The voltage divider includes two resistor in series and is coupled to the operational amplifier output terminal. Each of the transistors has a collector corresponding to one of the operational amplifier input terminals, a base corresponding to one of the voltage divider resistor terminals, and an emitter coupled to a common voltage terminal. The non-linear temperature-dependent element is disposed between the voltage divider output terminal providing the lower voltage and the common voltage terminal.
    Type: Grant
    Filed: October 1, 1997
    Date of Patent: January 9, 2001
    Assignee: Sipex Corporation
    Inventor: Alex Gusinov
  • Patent number: 6172553
    Abstract: A circuit comprising a positive switch and a steering network. The positive switch may be configured to present a first and a second switch signal in response to a first select signal. The steering network may be configured to present a high voltage output that may transition between a very high positive and a very low negative voltage, where the transition may respond to a high positive voltage input, a low negative voltage input, a first and second switch signal, and a second select signal.
    Type: Grant
    Filed: June 25, 1998
    Date of Patent: January 9, 2001
    Assignee: Cypress Semiconductor Corp.
    Inventors: Kenelm Murray, Donato Montanari
  • Patent number: 6169444
    Abstract: A regulating system (10) for a charge pump (12) employing a detection sub-circuit (28) and an enable sub-circuit (30) to operate an oscillator (26) and a channel-switching sub-circuit (32) in an automatic manner producing many of the advantages of previously unreconcilable skip mode and constant frequency mode type regulation. The detection sub-circuit (28) compares a feedback signal (52) from the output terminal (18) of the charge pump (12) to a reference signal (56) and produces an error signal (42) representative of output voltage deviation. Concurrently, the enable sub-circuit (30) compares a threshold signal (72) set for a minimum energy quanta which it is efficient for the flying capacitor (24) of the charge pump (12) to transfer to the error signal (42) and produces an enable signal (38) to enable the oscillator (26).
    Type: Grant
    Filed: July 15, 1999
    Date of Patent: January 2, 2001
    Assignee: MAXIM Integrated Products, Inc.
    Inventor: Charles R. Thurber, Jr.
  • Patent number: 6166589
    Abstract: The present invention relates to a reference voltage generator circuit for a semiconductor device that enables generating a reference voltage considering various parameters such as temperature variation. There is provided a reference voltage generator circuit coupled between a power supply voltage and a ground voltage for generating a reference voltage responsive to a plurality of current path control signals. A control circuit generates the plurality of the current path control signals. The control circuit includes a voltage division circuit coupled between the power supply voltage and the ground voltage for generating a divided voltage responsive to a plurality of externally applied code signals. A comparison circuit compares the divided voltage and the reference voltage and generates a comparison signal as a result of the comparison.
    Type: Grant
    Filed: September 2, 1999
    Date of Patent: December 26, 2000
    Assignee: Samsung Electronics, Co., Ltd.
    Inventor: Jong-Min Park
  • Patent number: 6166583
    Abstract: There is disclosed a semiconductor device in which capacitor means are connected to multiple input terminals via latch means, and the terminals on one side of the capacitor means are commonly connected to the input of a sense amplifier, thereby attaining a reduction of the circuit scale, improvement of the operation speed, saving of the consumption power, reduction of the manufacturing cost, and improvement of the manufacturing yield.
    Type: Grant
    Filed: October 26, 1995
    Date of Patent: December 26, 2000
    Assignee: Canon Kabushi Kaisha
    Inventors: Tetsunobu Kochi, Mamoru Miyawaki
  • Patent number: 6166587
    Abstract: A current reference generator comprises a pair of identical units (G1, G2) which generate respective current references (I1, I2), and a circuit (CL) for the linear combination of the two references. In each of the two units, the elements (S1, S2) which, by their current-voltage characteristics, determine the working point comprise respectively a single transistor (T1) and a pair of transistors (T2, T3), of the same type as the first, connected in series. A differential amplifier (AD) maintains stable the working point of the respective unit as power supply voltage varies. (FIG.
    Type: Grant
    Filed: September 29, 1999
    Date of Patent: December 26, 2000
    Assignee: CSELT-Centro Studi E Laboratori Telecomunicazioni S.p.A.
    Inventors: Marco Burzio, Emanuele Balistreri
  • Patent number: 6166578
    Abstract: A circuit arrangement (100) is coupled to a resistor (150) having at least two portions (110, 120). The arrangement (100) provides a substantially linear performance of the resistor (150). The arrangement (100) comprises a differential difference amplifier (160) (with input stages (170, 180) and output stage (190)) and a feedback unit (130). The input stages (170, 180) modify first (161) and second (162) measurement signals (e.g., (V.sub.B -V.sub.A) and (V.sub.A -GND), respectively) from the resistor portions (110, 120) to intermediate signals (OPH, OMH, OPL, OML). The output stage (190) differentially amplifies sums (at nodes 191, 192) of the intermediate signals and provides a control signal (CONTROL) which corresponds to a magnitude difference between the first and second measurement signals. The feedback unit (130) receives the control signal and supplies a corrective current (I) to the resistor (150) to offset non-linearity.
    Type: Grant
    Filed: August 31, 1998
    Date of Patent: December 26, 2000
    Assignee: Motorola Inc.
    Inventors: Joseph Shor, Vladimir Koifman, Yachin Afek
  • Patent number: 6166585
    Abstract: A charge pump circuit includes MOS capacitors configured to operate in the accumulation region, resulting in a substantially constant capacitance over the operational range. In a particularly preferred embodiment, a char ge pump uses multiple stages of p-channel MOS capacitors. In accordance with a further aspect of the present invention, oxide thicknesses of the p-channel MOS capacitors are optimized in accordance with the requirements of each stage.
    Type: Grant
    Filed: August 31, 1998
    Date of Patent: December 26, 2000
    Assignee: Conexant Systems, Inc.
    Inventor: Cristiano Bazzani
  • Patent number: 6163191
    Abstract: In a non-volatile memory capable of electrically rewriting data, a timer circuit for determining writing time that is operable at any time at a voltage of under 1.0 V. The timing circuit has a regulated voltage circuit for outputting a regulated output voltage no greater than 1.0 V, a constant current circuit for producing a constant current having a value determined by the regulated output voltage, a voltage comparing circuit for comparing an input voltage input to one terminal with a reference voltage input to another terminal, and a capacitive element connected to a constant current output terminal of the constant current circuit.
    Type: Grant
    Filed: June 12, 1998
    Date of Patent: December 19, 2000
    Assignee: Seiko Instruments Inc.
    Inventor: Masanori Miyagi
  • Patent number: 6160440
    Abstract: A scaleable charge pump. The charge pump is configured on an integrated circuit device that operates at a supply voltage and includes a predetermined number of pump stages coupled in series, at least one of the stages being coupled to receive a first pumped clock signal. An output node coupled in series to one end of the predetermined number of series coupled pump stages provides a pumped output voltage.
    Type: Grant
    Filed: September 25, 1998
    Date of Patent: December 12, 2000
    Assignee: Intel Corporation
    Inventors: Jahanshir J. Javanifard, Mase J. Taub