Patents Examined by Toan Tran
  • Patent number: 6642749
    Abstract: A tri-state sense amplifier is provided, which includes an enable input, a latch and an output driver. The latch has first and second complementary inputs and first and second complementary latch outputs, which are gated by the enable input. The output driver includes a data output, a pull-up transistor coupled to the data output and having a control terminal coupled to the first latch output, and a pull-down transistor coupled to the data output and having a control terminal coupled to the second latch output.
    Type: Grant
    Filed: September 27, 2002
    Date of Patent: November 4, 2003
    Assignee: LSI Logic Corporation
    Inventors: Sifang Wu, Steven M. Peterson, Mai T. MacLennan
  • Patent number: 6642767
    Abstract: DC offset canceling is disclosed. A DC level fixing signal generator receives feedback input of two output signals from a mixer and generates a level fixing control signal to fix the DC level of the two output signals according to the input values. A DC offset canceling signal generator receives feedback input of two output signals from the mixer and generates offset canceling control signals to cancel the relative difference between the DC levels of the two output signals according to the input values. A DC level fixing and offset canceling circuit fixes the DC level of each of the two output signals from the mixer and cancels the relative difference between the DC levels of the two output signals according to the level fixing control signal and the offset canceling control signals.
    Type: Grant
    Filed: September 16, 2002
    Date of Patent: November 4, 2003
    Assignee: Berkana Wireless, Inc.
    Inventor: Sung-ho Wang
  • Patent number: 6642772
    Abstract: Current mirror circuits that are parts of a first circuit and a second circuit, respectively, allow the same constant current to flow through the input side and the output side. Therefore, the base-emitter voltages of transistors Tr1 and Tr4, which tend to vary due to a temperature variation, can be set identical and hence can cancel out each other sufficiently. The same is true of the base-emitter voltages of transistors Tr5 and Tr8. Therefore, an input signal can be converted by a function having reference voltages as change points without being affected by temperature. Desired function circuits can be obtained by combining first circuits and second circuits in various manners.
    Type: Grant
    Filed: October 15, 2002
    Date of Patent: November 4, 2003
    Assignee: Alps Electric Co., Ltd.
    Inventors: Daisuke Takai, Kazuo Hasegawa
  • Patent number: 6639430
    Abstract: In a latch circuit having a bistable pair of cross connected transistors of a first polarity and a third transistor of a second polarity, a current signal greater than a bias current is received at a latch circuit port, amplified with the third transistor, and applied to the latch circuit port. This decreases the time in which the latch circuit port receiving the current signal greater than the bias current reaches a steady state voltage.
    Type: Grant
    Filed: February 27, 2002
    Date of Patent: October 28, 2003
    Assignee: Broadcom Corporation
    Inventors: Klaas Bult, Rudy Van de Plassche, Jan Mulder
  • Patent number: 6639445
    Abstract: The gate terminals of several Pch transistors are connected to an output terminal and controlled with second and third potentials. The gate terminals of several Nch transistors are connected to the output terminal and controlled with first and fourth potentials. In this way, an input signal between a VDD potential and a GND potential can be level-shifted to an output signal between a VPP potential and a VBB potential with a simple circuit structure. Also, the operation speed in switching potentials can be improved.
    Type: Grant
    Filed: August 9, 2002
    Date of Patent: October 28, 2003
    Assignee: Seiko Epson Corporation
    Inventor: Akira Maruyama
  • Patent number: 6639431
    Abstract: A comparator circuit is disclosed that senses a differential input polarity even when operating with a common mode voltage near the power rails (e.g., 50 millivolts) and under a wide range of process, temperature, and power supply conditions. In one aspect, the comparator circuit uses a complementary pair of P-type and N-type differential amplifiers. A combined P-type and N-type differential amplifier provides good transconductance even with a common mode voltage near either voltage rail. Consequently, a larger current swing than prior art circuits is provided to a current-to-voltage converter, which results in an overall faster circuit. In another aspect, a bias circuit drives a source follower that biases transistors in the differential amplifiers to ensure high transconductance and, consequently, high gain. Thus, the disclosed comparator senses differential input polarity even with a common mode voltage of only 50 millivolts or less.
    Type: Grant
    Filed: March 29, 2002
    Date of Patent: October 28, 2003
    Assignee: Lattice Semiconductor Corporation
    Inventor: Dale A. Potter
  • Patent number: 6639437
    Abstract: A level-turning point of input data is detected; and a sampling clock is generated in response to the level-turning point of the input data. The input data are sampled in synchronization with the sampling clock.
    Type: Grant
    Filed: January 14, 2003
    Date of Patent: October 28, 2003
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Kenichi Natsume
  • Patent number: 6636097
    Abstract: The invention relates to a method and to an input circuit for evaluating a data item in a data signal at an input of a memory component. The data signal is integrated between a start time and an end time that are specified by a control signal. An integration period between the start time and the end time depends on the frequency of the data signal. The data item is assigned a logic data value based on the result of the integration. The input circuit has a comparator device, an integration device and a switching device. The data signal is first integrated in order to obtain an integration value. The comparator device compares the integration value with a prescribed threshold value. A logic data value is assigned to the data item based on the result of the comparison.
    Type: Grant
    Filed: July 1, 2002
    Date of Patent: October 21, 2003
    Assignee: Infineon Technologies AG
    Inventors: Hermann Ruckerbauer, Andre Schäfer
  • Patent number: 6636089
    Abstract: In an integrated circuit, a detection device detects a drop in the supply voltage of the core of the integrated circuit or an excessively slow build-up of this voltage with respect to a supply voltage of the input/output interface circuits of the integrated circuit. Outputs of the interface circuits are set to a high impedance state by the detection device to minimize their power consumption.
    Type: Grant
    Filed: April 1, 2002
    Date of Patent: October 21, 2003
    Assignee: STMicroelectronics SA
    Inventors: Sylvain Majcherczak, Guy Mabboux
  • Patent number: 6633193
    Abstract: A switching device (20) is formed to generate a ramp voltage by using a capacitor (48) formed on the semiconductor die (90) with the switching device (20). The switching device (20) drives a high-power device to conduct load currents for a load. The ramp voltage is used to gradually increase the drive that is applied to the high-power device in order to gradually increase the current conducted by the high-power device.
    Type: Grant
    Filed: April 8, 2002
    Date of Patent: October 14, 2003
    Assignee: Wells Fargo Bank Minnesota, National Association, as Collateral Agent
    Inventors: Josef Halamik, Frantisek Sukup
  • Patent number: 6633192
    Abstract: A first and second circuits are connected in parallel between a first supply line supplying a first potential and a second supply line supplying a second potential. Each of the first and second circuits has first and second P-type transistors and an N-type transistor connected in series in order from the first-supply-line side. The gate of the first P-type transistor in the first circuit is connected to the drain of the N-type transistor in the second circuit. The gate of the first P-type transistor in the second circuit is connected to the drain of the N-type transistor in the first circuit. Input potentials opposite to each other are applied to the gates of the N-type transistors in the first and second circuits respectively and output potentials level-shifted from the input potentials are output from the drains of the N-type transistors in the first and second circuits respectively.
    Type: Grant
    Filed: August 14, 2001
    Date of Patent: October 14, 2003
    Assignee: Seiko Epson Corporation
    Inventor: Masahiko Tsuchiya
  • Patent number: 6630847
    Abstract: A full rail-to-rail CMOS comparator is provided. The comparator includes a gain stage and a bias stage. The bias stage is responsive to the common mode input voltage level to provide a bias signal that maintains the gain stage with an optimum operating range regardless of the level of the common mode input voltage, thus maintaining the comparator output responsive to the differential input voltage. Accordingly, when operating in the optimum operating range, duty cycle distortion of the signal at the comparator output is minimized. The comparator also offers improved performance due to a lower component count and fewer comparator stages, thus decreasing power consumption and improving propagation delays.
    Type: Grant
    Filed: December 31, 2002
    Date of Patent: October 7, 2003
    Assignee: Micron Technology, Inc.
    Inventor: Ken S. Hunt
  • Patent number: 6628150
    Abstract: Transitions (e.g. high to low and/or low to high) associated with operation of the driver are employed to implement control, which can be applied as a pulse in response to an occurrence of the transition. The control operates to speed up the transition at the output of the driver, such as can reduce driver switching times and enable a corresponding increase in data transmission rates.
    Type: Grant
    Filed: April 2, 2002
    Date of Patent: September 30, 2003
    Assignee: Texas Instruments Incorporated
    Inventors: Fernando D. Carvajal, Mark W. Morgan, Srikanth Gondi
  • Patent number: 6628147
    Abstract: A comparator comprises a switching means for supplying two different threshold voltages to the comparator upon a first and a second control signal, respectively. The second control signal is enabled by a rising or a falling edge of the comparator output that is coupled to a control means providing the second control signal. The time interval that a varying input signal requires to change its amplitude crossing and in between the two threshold voltages can thus be detected by two subsequent rising or falling edges of the comparator output without the adverse influence of the comparator's meta-stability.
    Type: Grant
    Filed: June 27, 2002
    Date of Patent: September 30, 2003
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Lutz Dathe, Thorsten Riedel
  • Patent number: 6621309
    Abstract: To improve a control circuit for at least one inductive load, comprising a first load branch, which lies between a first voltage terminal and a second voltage terminal and comprises an electronic switch and the inductive load connected in series, the electronic switch lying between a first terminal of the inductive load and the first voltage terminal, and a second terminal of the inductive load being in connection with the second voltage terminal, a freewheeling diode, via which a freewheeling current of the inductive load flows when the electronic switch is open, in such a way that smallest possible fluctuations of the supply current and smallest possible voltage peaks occur at the voltage terminals, it is proposed that there is provided a freewheeling branch which has, as a series connection, a capacitance connected to the first voltage terminal and an inductance connected to the second terminal of the inductive load, and also a freewheeling diode lying between a center tap between the capacitance and the i
    Type: Grant
    Filed: August 8, 2002
    Date of Patent: September 16, 2003
    Assignee: AFL Germany Electronics GmbH
    Inventors: Matthias Roder, Horst Flock
  • Patent number: 6621319
    Abstract: An edge-triggered flip-flop circuit in which a pair of capacitors are alternately charged and discharged to voltages approximating supply rail values and, in combination of with a small number of switches, present high or low impedance paths for input signal transitions of a predetermined polarity to trigger state changes. In an alternative embodiment large switching capacitors are avoided in a circuit that employs a pair of pass-transistor configurations to connect respective capacitors to output terminals of a bistable device. The voltages on the capacitors track the corresponding bistable device output voltages when the input signal is in a given state (illustratively low), and store the value of the corresponding voltage when turned off by the (illustratively high) other state of the input signal. Then, the voltage on the capacitors and the selected input signal transition is used to effectively trigger a transition in the bistable device.
    Type: Grant
    Filed: September 29, 1999
    Date of Patent: September 16, 2003
    Assignee: Agere Systems Inc.
    Inventors: Ruben Herrera, Rahul Sarpeshkar
  • Patent number: 6617886
    Abstract: A buffer circuit includes a differential pair output switch having an additional NPN device and resistor operational to increase the common mode output voltage of the buffer during a switching event, such that the voltage movement at the common emitter node of the differential pair output switch for the buffer circuit is decreased to substantially reduce distortion of an output signal associated with a DAC that employs the buffer circuit.
    Type: Grant
    Filed: June 26, 2002
    Date of Patent: September 9, 2003
    Assignee: Texas Instruments Incorporated
    Inventors: William J. Bright, Ranjit Gharpurey
  • Patent number: 6617888
    Abstract: The invention provides a low voltage differential signaling driver (LVDS) which can operate with a lower supply voltage than conventional LVDS drivers. The common-mode voltage of the driver circuit is set to a certain level, or maintained within a certain range, by adjusting the driver current, the pull-up resistance, or both. In one implementation, the common-mode voltage of a differential driver circuit is regulated via a feedback signal.
    Type: Grant
    Filed: January 2, 2002
    Date of Patent: September 9, 2003
    Assignee: Intel Corporation
    Inventor: Andrew M. Volk
  • Patent number: 6617906
    Abstract: Systems and methods are provided for limiting voltage to low-voltage devices employing a high-voltage supply. The systems and methods employ voltage limiting devices to bias cascode devices. The cascode devices are serially connected from a high-voltage supply to a low-voltage node. The voltage limiters are serially connected from the high-voltage supply to ground to bias the cascode devices. Current sources are connected in parallel with the voltage limiters except the one connected to ground. If the current sources are set to deliver substantially equal currents, then the order in which the cascode transistors are biased becomes nondeterministic, but the circuit continues to finction and the overall supply current is thereby minimized.
    Type: Grant
    Filed: October 1, 2002
    Date of Patent: September 9, 2003
    Assignee: Texas Instruments Incorporated
    Inventor: Roy Alan Hastings
  • Patent number: 6617897
    Abstract: The present invention discloses an output circuit that is able to adjust the output voltage slew rate and avoid short-circuit current, comprising: a control circuit for receiving an input data and generating a first set of control signals based on the input data; an output control device consisting of a first field effect transistor (FET) connected in series with a second field effect transistor (FET) and the point of connection is the output end for generating an output signal; a first capacitor having one end connected to a first working voltage and generates a first control voltage by charging/discharging on another end to control the gate of the first field effect transistor; a first switch for controlling charging/discharging of the first capacitor device based on the first set of control signals; a first current source for providing charging current for the first capacitor device; a second capacitor having one end connected to a second working voltage and generates a second control voltage by charging/d
    Type: Grant
    Filed: September 27, 2002
    Date of Patent: September 9, 2003
    Assignee: Realtek Semiconductor Corp.
    Inventor: An-Ming Lee