Field Effect Transistor Patents (Class 341/136)
  • Patent number: 9438268
    Abstract: This D/A converter includes a plurality of D/A converter elements, each comprising current sources configured to supply output currents to output nodes, and first switches configured to control the output currents. The output nodes are connected to a capacitor section having second switches and a capacitive load. The D/A converter further includes a switch control circuit configured to control the first switches responsive to digital signals, and also control the second switches in accordance with the control of the ON/OFF state of the first switches.
    Type: Grant
    Filed: January 8, 2016
    Date of Patent: September 6, 2016
    Assignee: SOCIONEXT INC.
    Inventors: Yosuke Mitani, Takashi Morie, Kazuo Matsukawa, Masashi Uchida
  • Patent number: 9432048
    Abstract: A D/A conversion circuit includes a plurality of resistors connected to each other in series, a plurality of MOS transistors connected to each other so as to correspond to a plurality of contacts, and a plurality of dummy electrodes respectively disposed on sides opposite to the plurality of MOS transistors with a resistive element interposed therebetween when seen in a plan view of a semiconductor substrate. Each of the dummy electrodes is set to be in a second potential state when a gate electrode of the MOS transistor disposed on a side opposite thereto with the resistive element interposed therebetween is in a first potential state, and is set to be in a first potential state when the gate electrode of the MOS transistor is in a second potential state.
    Type: Grant
    Filed: January 14, 2016
    Date of Patent: August 30, 2016
    Assignee: Seiko Epson Corporation
    Inventor: Shigenori Isozaki
  • Patent number: 9425816
    Abstract: Data converters convert signals in analog form to digital form or from digital form to analog form. Due to mismatches between devices that are intended to be identical (unary elements), some data converters outputs may have undesirable characteristics, such as non-linearities. Shuffling the inputs to the unary elements based on a pseudo-random sequence is a technique that can average out the mismatches over time. However, shuffling generally requires a complex switch matrix, and can potentially impact the speed of the converter. To address mismatches, a high speed technique for rotating comparator thresholds is implemented to effectively rotate an array of unary digital-to-analog converter elements. The technique is particularly advantageous for addressing mismatches in unary digital-to-analog converters used for reconstructing a quantized analog signal within delta-sigma analog-to-digital converter.
    Type: Grant
    Filed: June 3, 2015
    Date of Patent: August 23, 2016
    Assignee: Analog Devices Global
    Inventors: Wenhua W. Yang, Richard E. Schreier
  • Patent number: 9413381
    Abstract: A low-power reconfigurable voltage-mode digital-to-analog converter (DAC) driver circuit includes a first and a second supply voltage and a number of DAC units. Each DAC unit is coupled to a respective bit of a digital input. The DAC units are configured to maintain a constant output impedance. Each DAC unit includes one or more complementary switch pairs that couple first nodes of one or more respective impedances to one of the first or the second supply voltage, based on the respective bit of the digital input. Second nodes of the one or more respective impedances are coupled to an output node.
    Type: Grant
    Filed: February 6, 2015
    Date of Patent: August 9, 2016
    Assignee: Broadcom Corporation
    Inventors: Anand Jitendra Vasani, Ali Nazemi, Jun Cao, Afshin Momtaz
  • Patent number: 9397676
    Abstract: Embodiments of the present disclosure provide improved switching techniques for controlling three-level DAC cells employing a return-to-hold scheme. Disclosed techniques include switching a DAC cell off for at least the duration of a time period between two hold periods while a digital value of zero is being converted. Because the DAC cell is switched off between two hold periods, the current source drain voltage is not disturbed during the critical transient times when D flip-flop outputs change, which happens during the hold periods, in response to change of digital values to be converted. In this manner, power consumption may be reduced while preserving the high performance properties of a three-level return-to-hold DAC.
    Type: Grant
    Filed: September 29, 2015
    Date of Patent: July 19, 2016
    Assignee: Analog Devices, Inc.
    Inventor: Khiem Quang Nguyen
  • Patent number: 9385742
    Abstract: A current switching cell for a digital to analog converter. The switching cell includes three stages, a first control stage, a data stage, and a second control stage. The first control stage is configured to either disconnect the outputs of the digital to analog converter, or to connect them to the outputs of the data stage. The data stage is configured to operate in one of two states, depending on a data signal received, and the second control stage is configured to selectively invert the output of the digital to analog converter. The two control stages may be driven with several combinations of control waveforms to implement a non return to zero mode, a return to zero mode, inverse non return to zero mode, and inverse return to zero mode.
    Type: Grant
    Filed: November 16, 2015
    Date of Patent: July 5, 2016
    Assignee: RAYTHEON COMPANY
    Inventors: William W. Cheng, Michael H. Liou
  • Patent number: 9368996
    Abstract: Provided are an apparatus and a method for simultaneously transmitting and receiving a wireless power and data. A wireless power and data transmission apparatus may include: a modulator configured to modulate first data by adjusting a power amount to be charged in one or more capacitors; a switch controller configured to control one or more switches corresponding the one or more capacitors based on a charging time to charge the one or more capacitors and a transfer time to transfer a power charged in the one or more capacitors and the modulated first data to a source resonator; and a transmitter configured to transmit the charged power and the modulated first data using the source resonator.
    Type: Grant
    Filed: September 9, 2011
    Date of Patent: June 14, 2016
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Sang Joon Kim
  • Patent number: 9323273
    Abstract: A current source circuit is configured to receive a reference current at the input circuit path of a current mirror circuit. The current mirror circuit mirrors the reference current and generates mirror currents at a number of output circuit paths. A corresponding number of control transistors are connected in series with the output circuit paths. Each control transistor is selectively actuated in response to a control signal. A decoder circuit is configured to receive a variable control signal and generate actuation signals in response thereto to selective actuate the control transistors to pass the mirror current to an output node. At the output node, the passed mirror currents are summed to generate a variable output current. The variable current is monotonically modulated in response to the variable control signal.
    Type: Grant
    Filed: October 2, 2014
    Date of Patent: April 26, 2016
    Assignee: STMICROELECTRONICS (SHENZHEN) R&D CO. LTD
    Inventors: Meng Wang, Xue Lian Zhou
  • Patent number: 9325337
    Abstract: In contrast to some existing techniques, a calibration technique compares multiple outputs which may be, for example, successive or different outputs from the digital-to-analog converter (DAC) in an analog environment and determines differences between at least two outputs in an analog environment. A feedback signal is provided in the digital environment to provide an internal or self-calibration regime. The digital feedback signal is provided to a digital signal processing (DSP) component of the calibration circuitry which uses the feedback signal to determine appropriate input codes to provide to the DAC. The same DAC can be used for both signal generation and feedback DAC purposes, and this provides a self-calibration of the DAC performance which is typically related to the integral non-linearity (INL) characteristics of the DAC transfer function.
    Type: Grant
    Filed: January 9, 2015
    Date of Patent: April 26, 2016
    Assignee: ANALOG DEVICES GLOBAL
    Inventor: Dennis A. Dempsey
  • Patent number: 9288416
    Abstract: A reference voltage circuit for generating a reference voltage to be referred when a pixel signal is digitally converted, includes ramp voltage generating means for generating a ramp voltage which drops from a predetermined initial voltage at a certain gradient, a transistor for forming, together with the ramp voltage generating means, a current mirror circuit, and gain change means for changing a current value of a current flowing from a predetermined power supply via the transistor to change the gradient of the ramp voltage generated by the ramp voltage generating means.
    Type: Grant
    Filed: May 19, 2015
    Date of Patent: March 15, 2016
    Assignee: SONY CORPORATION
    Inventor: Hayato Wakabayashi
  • Patent number: 9264060
    Abstract: A new approach is disclosed concerning offset cancellation methods in analog to digital converters and analog to digital converters implementing the same. Such approach allows to efficiently cancel offset drifts in analog to digital converters.
    Type: Grant
    Filed: November 7, 2013
    Date of Patent: February 16, 2016
    Assignee: ST-ERICSSON SA
    Inventors: Pierangelo Confalonieri, Federico Guanziroli, Alberto Minuti
  • Patent number: 9214953
    Abstract: A multi-level data weighted averaging circuit for inclusion in a multi-bit DAC circuit has a thermometer encoder that includes a binary to thermometer code conversion array configured for retaining or generating a multi-bit code representing an amplitude to be developed by each of the DAC element of the DAC circuit. The thermometer encoder is in communication with a multi-bit delta/sigma modulator to receive an oversampled binary coding representing an amplitude of a sampling of an analog signal. The oversampled binary coding is applied to an element selector to select the elements retaining or generating the element binary strings of bits of the multi-bit thermometer code. The multi-bit thermometer code is transferred to a rotational dynamic element matching circuit that rotationally selects order that the DAC elements are to receive each of the element binary strings of bits of the multi-bit thermometer code.
    Type: Grant
    Filed: September 8, 2014
    Date of Patent: December 15, 2015
    Assignee: Dialog Semiconductor (UK) Limited
    Inventor: Zakaria Mengad
  • Patent number: 9210349
    Abstract: In an A/D conversion circuit and a solid-state imaging device, a latch circuit is in a disable state until a first timing at which an output signal of a comparison unit has been inverted, and is in an enable state until a second timing at which a delay time of the inversion delay circuit has passed from the first timing. The latch circuit is in the enable state until the second timing according to comparison start in the comparison unit. The latch circuit latches an output signal of a delay unit at the second timing. A determination unit determines whether the latch circuit accurately latches the output signal of the delay unit, and outputs a signal indicating a determination result to a delay controller. The delay controller controls the delay time of the inversion delay circuit based on the determination result.
    Type: Grant
    Filed: November 19, 2013
    Date of Patent: December 8, 2015
    Assignee: OLYMPUS CORPORATION
    Inventor: Susumu Yamazaki
  • Patent number: 9098104
    Abstract: A low drop out voltage regulator comprising: a transistor having an input node, an output node, and a control node; a differential amplifier having an output connected to the control node of the transistor and having a first input node; and a feedback capacitor connected between the output node of the transistor and the first input of the differential amplifier, wherein a voltage at the output of the transistor is dependent on a charge across the feedback capacitor.
    Type: Grant
    Filed: March 7, 2013
    Date of Patent: August 4, 2015
    Assignee: ANALOG DEVICES GLOBAL
    Inventors: Ramon Tortosa Navas, Enrique Company Bosch, Santiago Iriarte
  • Patent number: 9081395
    Abstract: A direct current (DC) power supply apparatus includes an input unit configured to receive an outside DC power; a plurality of polarity correction units configured to correct the polarity of the outside DC power; a plurality of switch units installed to correspond to each of the plurality of polarity correction units; a detection unit configured to detect a flow of current of the plurality of polarity correction unit; and a control unit configured to determine a polarity correction unit, at which current of DC power flows, among the plurality of correction units based on a detection signal of transmitted from the detection unit, and control the switch unit corresponding to the determined polarity correction unit at an ON position such that the current of DC power flows through the switch unit which is controlled at the ON position.
    Type: Grant
    Filed: January 31, 2013
    Date of Patent: July 14, 2015
    Assignees: SAMSUNG ELECTRONICS CO., LTD., SUNGKYUNKWAN UNIVERSITY RESEARCH & BUSINESS FOUNDATION
    Inventors: Hyun Cheol Jin, Sun Jin Kim, Han Sol Seo, Seung Min Shin, Byoung Kuk Lee, Joon Young Jeon
  • Patent number: 9046573
    Abstract: Test circuitry for characterizing manufacturing variations in semiconductor devices is provided. The test circuitry may include an array of devices under test and associated decoder circuitry for addressing the array of devices under test. In one arrangement, the test circuitry may be formed on a wafer at a scribe line located between adjacent integrated circuit dies on the wafer. In another arrangement, the test circuitry may be formed within an integrated circuit to provide on-chip variation monitoring capabilities. A measurement circuit may be used to gather test data from the array of devices under test and may be used to generate control signals that compensate for the manufacturing variations detected in the array of devices under test.
    Type: Grant
    Filed: December 20, 2013
    Date of Patent: June 2, 2015
    Assignee: Altera Corporation
    Inventor: Jeffrey T. Watt
  • Patent number: 9035680
    Abstract: Embodiments of the present invention provide a comparator and an analog-to-digital converter. A sampling module, a pre-amplifying module, and a coupling module in the comparator obtain a third differential voltage signal according to a positive input signal and a negative reference signal, and obtain a fourth differential voltage signal according to a negative input signal and a positive reference signal. A latch that is in the comparator and formed by a first P-type field effect transistor, a second P-type field effect transistor, a third field effect transistor, a fourth field effect transistor, a first switch, and a second switch is directly cross-coupled through gates, and directly collects the third differential voltage signal and the fourth differential voltage signal to the gates, so as to drive the latch to start positive feedback.
    Type: Grant
    Filed: October 8, 2014
    Date of Patent: May 19, 2015
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Jinda Yang, Liren Zhou, Jun Xiong
  • Patent number: 9000812
    Abstract: An apparatus relating generally to a current steering cell includes a first bleeder circuit, a second bleeder circuit, a steering circuit, and an output circuit. The first bleeder circuit and the second bleeder circuit are coupled to receive a first current-source bias voltage. The steering circuit is coupled to receive a second current-source bias voltage independent from the first current-source bias voltage.
    Type: Grant
    Filed: April 4, 2014
    Date of Patent: April 7, 2015
    Assignee: Xilinx, Inc.
    Inventors: Donnacha Lowney, Christophe Erdmann
  • Patent number: 8994569
    Abstract: The semiconductor integrated circuit device includes a T-type switch circuit TS[k] that is between an input port A[k] and an input terminal Ain of an analog/digital conversion circuit and that includes first, second, and third PMOS transistors MP1, MP2, and MPc, and first, second, and third NMOS transistors MN1, MN2, and MNc; and a fourth PMOS transistor MPu for pre-charging the input terminal Ain to a power supply voltage VCCA. In detecting the presence or absence of a disconnection from the input port A[k] to a signal input terminal Vint[k], first, the input terminal Ain is pre-charged to the power supply voltage VCCA via the fourth PMOS transistor MPu and also the second NMOS transistor MN2 and the second PMOS transistor MP2 are turned on, and the first NMOS transistor MN1, the first PMOS transistor MP1, the third PMOS transistor MPc, and third the NMOS transistor MNc are turned off.
    Type: Grant
    Filed: September 11, 2013
    Date of Patent: March 31, 2015
    Assignee: Renesas Electronics Corporation
    Inventors: Tomohiko Ebata, Takuji Aso
  • Patent number: 8988259
    Abstract: A data converter can include a resistor network, a switch network connected to the resistor network and having a plurality of switch circuits, each with an NMOS and a PMOS switch transistor, and a voltage generator to generate a drive voltage for driving a gate of at least one of the NMOS or PMOS switch transistors of at least one of the switch circuits. The voltage generator can include first and second pairs of transistors, each pair having connected control terminals and being connected to a second NMOS or PMOS transistor, a first or second resistor, and the other pair of transistors. The first and second resistors can have substantially equal resistance values. A ratio of width-to-length ratios of the second NMOS to PMOS transistors can be substantially equal to such a ratio of the switch circuit NMOS to PMOS transistors.
    Type: Grant
    Filed: February 19, 2013
    Date of Patent: March 24, 2015
    Assignee: Analog Devices Global
    Inventors: Avinash Gutta, Alan Gillespie, Roderick McLachlan
  • Patent number: 8988266
    Abstract: A method, comprising: receiving an analog input; determining an upper outer rail and a lower outer rail as polling values to be used by voltage comparators; blanking at least three comparators; determining which two of the at least three comparators are closest to the input analog voltage levels; defining the two comparators which are closest to the analog input signal to be the next comparators of the next sampling process; assigning a remaining comparator at a voltage level in between the new top and bottom voltage levels; enabling the outer rails, but blanking the inner rail; progressively narrowing down the voltage range spanned by the two outer comparators; and generating a 2-tuple value of an asynchronous voltage comparator crossing.
    Type: Grant
    Filed: February 28, 2014
    Date of Patent: March 24, 2015
    Assignee: Texas Instruments Incorporated
    Inventors: Janakiraman S, Udayan Dasgupta, Ganesan Thiagarajan, Abhijit A. Patki, Madhulatha Bonu, Venugopal Gopinathan
  • Patent number: 8928513
    Abstract: A current steering digital-to-analog converter (DAC) switch driver circuit is provided. The circuit is composed of a conditioning module having a signal input to accept a binary logic digital signal, and signal outputs to supply differential driver signals V+ and V? with a low voltage level (Vlow) greater than the binary logic digital signal low voltage level. Typically, Vlow has a greater potential than ground (0V). A DAC current steering cell has a signal input to accept the differential driver signals and an output to supply a differential analog current responsive to the differential driver signals. The DAC current steering cell may be an NMOS DAC current steering cell. The conditioning module may be a CMOS switch driver, or composed of a level shifter followed by a CMOS switch driver.
    Type: Grant
    Filed: September 18, 2014
    Date of Patent: January 6, 2015
    Assignee: IQ-Analog Corporation
    Inventor: Mikko Waltari
  • Patent number: 8928512
    Abstract: A digital to analog converter and a method for controlling a current source array in a digital to analog converter relate to the field of electronics technologies, and are used to reduce a system error. The digital to analog converter includes: a decoding module, a switch array, and a current source array, where the decoding module is configured to generate a 2n?1-bit first temperature code by using high n bits of an input 2n-bit binary digital signal, generate a 2n?1-bit second temperature code by using low n bits of the 2n-bit binary digital signal, and control, by using the 2n?1-bit first temperature code and the 2n?1-bit second temperature code, a working sequence of 2n×2n?1 unit switches.
    Type: Grant
    Filed: December 27, 2013
    Date of Patent: January 6, 2015
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Haiquan Yuan, Peng Gao
  • Patent number: 8922409
    Abstract: A switch-driving circuit and a Digital-to-Analog Converter (DAC) using the switch-driving circuit are provided. The switch-driving circuit includes a main cell and a reference cell. The main cell includes a current source and a resistance-control component electronically connected to the current source. The reference cell is coupled to the current source and the resistance-control component, and includes a first loop, the first loop is configured to track a target reference voltage so as to provide at least one first control voltage to control a resistance change of the resistance-control component. The reference cell and the main cell are implemented by MOS transistors in place of capacitors which occupy an increased circuit area, rendering reduced circuit area for the switch-driving circuit, and decreasing manufacturing costs. Further, the switch-driving circuit outputs a voltage signal with reduced noise, increasing the performance of the Digital-to-Analog Converter.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: December 30, 2014
    Assignee: MediaTek Singapore Pte. Ltd.
    Inventors: Cheng Tao, Yue Feng, Kun Lan, Yu-Kai Chou
  • Patent number: 8890735
    Abstract: A multi-level sigma-delta Analog to Digital converter provides multi-level outputs using a quantizer with reduced quantization levels. The converter comprises a direct path comprising a computation block, an analog integrator and the quantizer with reduced quantization levels. Further, the converter comprises a feedback path arranged to provide to the computation block a feedback analog signal. The direct path comprises a first amplification block having a gain factor which is the inverse of the gain factor of a second amplification block of the feedback path. The converter allows reduction of the complexity of the quantizer.
    Type: Grant
    Filed: October 8, 2012
    Date of Patent: November 18, 2014
    Assignee: ST-Ericsson SA
    Inventor: Carlo Pinna
  • Patent number: 8872685
    Abstract: A digital-to-analog converter (DAC) includes, in part, a multitude of input stages that supply currents to a pair of current summing nodes in response to a digital signal, and an impedance attenuator coupled between the current summing nodes and the output of the DAC. The impedance attenuator is adapted, among other function, to increase the range of impedances of the output load, to account for changes in the output load impedance due to variations in the process, voltage and temperature, and to decouple the impedances seen by the summing nodes from the load impedance. The impedance attenuator further includes a differential-input, differential-output amplifier with programmable common-mode gain bandwidth to control the harmonic distortion of the amplifier. The impedance attenuator optionally includes a pair of cross-coupled capacitors to control the harmonic distortion of the amplifier.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: October 28, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Tongyu Song, Sang Min Lee, Derui Kong, Dongwon Seo
  • Patent number: 8836561
    Abstract: A D/A conversion circuit includes: current generation circuits each including a constant current source configured to generate a current, a first MOSFET connected to the constant current source and configured to control a supply destination of the current, a first gate control section configured to exclusively supply a first voltage and a second voltage to a gate of the first MOSFET, and a first discharge switch connected to the first gate control section and the gate of the first MOSFET, controlled to be turned on at the same time as the first gate control section supplies the second voltage and controlled to be turned off before the first gate control section supplies the first voltage; a first current addition line; a discharge line; a first resistor connected to the first current addition line; and a voltage source configured to supply the second voltage to the first gate control sections.
    Type: Grant
    Filed: September 12, 2013
    Date of Patent: September 16, 2014
    Assignee: Sony Corporation
    Inventors: Norifumi Kanagawa, Yasuhide Shimizu
  • Patent number: 8816887
    Abstract: A sampling circuit comprising: an input node; a first signal path comprising a first sampling capacitor and a first signal path switch in a signal path between the input node and a first plate of the first sampling capacitor; a second signal path comprising a second sampling capacitor and a second signal path switch in a signal path between the input node and a first plate of the second sampling capacitor, and a signal processing circuit for forming a difference between a signal sampled onto the first sampling capacitor and a signal sampled onto the second sampling capacitor.
    Type: Grant
    Filed: September 21, 2012
    Date of Patent: August 26, 2014
    Assignee: Analog Devices, Inc.
    Inventors: Christopher Peter Hurrell, Roberto Maurino
  • Patent number: 8736480
    Abstract: An apparatus and method of successive approximation analog-to-digital conversion for receivers comprising that during a sample mode, connecting an array of capacitors to a plurality of sampling switches coupled to a plurality of amplified input signals, and during a conversion mode, connecting in common the array of capacitors to a comparator and isolating the array of capacitors from the plurality of sampling switches. Additionally, filtering is done by the summation of samples at phase offsets.
    Type: Grant
    Filed: January 11, 2013
    Date of Patent: May 27, 2014
    Assignee: Intel Corporation
    Inventors: Nicholas P. Cowley, Isaac Ali, Viatcheslav I. Suetinov, Keith Pinson
  • Patent number: 8730083
    Abstract: According to an embodiment, there are provided a capacitor DAC for generating an output signal in accordance with a connection state of a capacitor element, a reference voltage generation circuit for supplying a reference voltage to the capacitor DAC, a comparator for outputting a comparison result in accordance with the output signal, a successive approximation register for outputting a digital signal in accordance with the comparison result, and a control circuit for controlling a connection state of the capacitor element in accordance with the comparison result and comparing an ideal code with a digital signal obtained by sampling a predetermined voltage, thereby correcting an error of the digital signal.
    Type: Grant
    Filed: September 11, 2012
    Date of Patent: May 20, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hirotomo Ishii, Tomohiko Sugimoto, Masanori Furuta
  • Patent number: 8723709
    Abstract: There is provided a digital-to-analog converter including: a mirror circuit including a first transistor to copy a reference current at a predetermined mirror ratio, and a second transistor cascade coupled with the first transistor; and an analog switch coupled with a gate of the second transistor, the analog switch being configured to be controlled, by a digital signal input from outside, so as to be turned on or off.
    Type: Grant
    Filed: September 5, 2012
    Date of Patent: May 13, 2014
    Assignee: Fujitsu Limited
    Inventor: Hideki Oku
  • Patent number: 8717220
    Abstract: Methods for reading a data location coupled to an electrical conductor. A counter receives a signal from an analog-to-digital converter coupled to the electrical conductor. The counter produces two or more counts, and in some embodiments, the counts are based in part on a variable reference voltage. An interfuser may be coupled to an output of the counter. The interfuser receives the two or more counts from the counter and reads data conveyed by the data location based on the two or more counts.
    Type: Grant
    Filed: November 29, 2011
    Date of Patent: May 6, 2014
    Assignee: Micron Technology, Inc.
    Inventor: R. Jacob Baker
  • Patent number: 8686886
    Abstract: A device monitoring unit obtains, through respective digital communication routes, a combination of a digital setting value for an analog output value to an analog communication route in a field device, a digital value of an AD converting device in an input/output unit, and one of the digital setting values stored in a memory of the input/output unit, to check the status of the communication through the analog communication route based on the values obtained.
    Type: Grant
    Filed: February 17, 2012
    Date of Patent: April 1, 2014
    Assignee: Azbil Corporation
    Inventors: Kouki Sasaki, Hiroyuki Tsugane
  • Patent number: 8681028
    Abstract: An analog to digital converter includes: a first pulse delay circuit forming a multi-stage delay unit of which each delay unit have a pulse signal delayed with a delay time responding to an input voltage; a first encoding circuit that detects the number of delay units in the first pulse delay circuit through which the pulse signal passes during a predetermined measurement period, and outputs the AD conversion data based on the number of delay units; and a timing generation circuit which, in response to receiving the start signal, generates an end signal when the input voltage of the first pulse delay circuit is a specified voltage within an allowable input voltage range, in order to determine the measurement period which is a time required for the pulse signal to pass through a predetermined number of the delay units which is specified in advance.
    Type: Grant
    Filed: September 19, 2012
    Date of Patent: March 25, 2014
    Assignee: DENSO CORPORATION
    Inventor: Tomohito Terazawa
  • Patent number: 8674866
    Abstract: In one method embodiment, receiving a data signal; and converting the data signal to an analog signal over plural clock cycles, the converting comprising: during a first clock cycle of the plural clock cycles, switching on one or more first current cells of a first bank while simultaneously a second bank comprising second current cells is switched off or almost off; and during a second clock cycle of the plural clock cycles, the second clock cycle immediately subsequent to the first clock cycle, switching on one or more of the second current cells of the second bank while simultaneously the first bank is switched off or almost off.
    Type: Grant
    Filed: June 21, 2012
    Date of Patent: March 18, 2014
    Assignee: Broadcom Corporation
    Inventors: Christopher Ward, Frank Van der Goes
  • Patent number: 8653995
    Abstract: This disclosure relates to a compensating for nonlinearity resulting from a capacitance feedback in current cells of a single ended digital to analog circuit.
    Type: Grant
    Filed: May 9, 2011
    Date of Patent: February 18, 2014
    Assignee: Intel Mobile Communications GmbH
    Inventor: Franz Kuttner
  • Patent number: 8643521
    Abstract: A DAC has at least one bit current-steering circuit. In the DAC, the current-steering circuit has a current source circuit, a switch, a feedback circuit, and an amplifier circuit. The current source circuit is disposed for outputting a bias current to the switch and coupled to the amplifier circuit. The switch has a first input/output terminal coupled to output an analog signal, a control terminal coupled to the feedback circuit, and a second input/output terminal for receiving the bias current, so that the first switch determines whether the first and the second input/output terminals are conducted according to a status of the control terminal.
    Type: Grant
    Filed: November 28, 2012
    Date of Patent: February 4, 2014
    Assignee: United Microelectronics Corp.
    Inventors: Hsueh-Chen Cheng, Wen-Hong Hsu, Po-Hua Chen, Yu-Yee Liow
  • Patent number: 8643520
    Abstract: An equalized-impedance shadowed current cell can be arrayed in a Digital-to-Analog Converter (DAC) or other converters or applications. The Equalized-impedance shadowed current cell has primary differential transistors in parallel with shadow differential transistors that have gates driven inversely to gates of the primary differential transistors. A shadow current from the shadow differential transistors is much smaller than a primary current switched by the primary differential transistors. Cell current is not switched off to zero but to the shadow current. The ON state and OFF state impedances of the current cell may be matched during circuit design so that the impedance is the same regardless of digital input values. The Width and Length of the shadow differential transistors are adjusted so that overall output impedances for the ON and OFF states of the current cell are matched. Since output impedance is input code independent, high-speed performance is improved.
    Type: Grant
    Filed: November 27, 2012
    Date of Patent: February 4, 2014
    Assignee: Hong Kong Applied Science & Technology Research Institute Company Ltd.
    Inventors: Xiao Huo, Beiping Yan, Zhongzi Chen, Xiaowu Cai
  • Patent number: 8624766
    Abstract: Embodiments of the present disclosure provide a method and system for an auto-ranging analog-to-digital converter (ADC) for dynamically scaling inputs to an ADC. The auto-ranging ADC includes a dynamically configurable transistor arrangement for delivering a load current and a replica device for replicating the load current. A current sense resistor generates a replicated load voltage based on the replicated current. The ADC generates a digital value based on the replicated load voltage. The auto-ranging ADC also includes an auto-ranging controller for dynamically configuring the transistor arrangement based on the digital value to scale the inputs to the ADC.
    Type: Grant
    Filed: November 30, 2011
    Date of Patent: January 7, 2014
    Assignee: Standard Microsystems Corporation
    Inventor: Srinivas K. Pulijala
  • Patent number: 8610609
    Abstract: The present disclosure provides techniques for using an NMOS field effect transistor-based buffer to buffer a pair of complementary digital signals and output a pair of equivalently fast rising and fast falling complementary signals to simultaneously drive a differential pair of PMOS transistors of a unit cell that output an analog signal for a current steering DAC. Accordingly, a DAC comprises a latch circuit and a unit cell circuit. The latch circuit includes an NMOS field effect transistor-based buffer and is capable of receiving a first digital signal and a clock signal and outputting a second digital signal through the NMOS field effect transistor-based buffer according to the clock signal. The second digital signal is associated with the first digital signal. The unit cell circuit, coupled to the latch circuit, receives the second digital signal and outputs an analog signal representative of the first digital signal.
    Type: Grant
    Filed: March 16, 2012
    Date of Patent: December 17, 2013
    Assignee: MStar Semiconductor, Inc.
    Inventor: Bernard Ginetti
  • Patent number: 8587463
    Abstract: A method of adaptively and losslessly quantizing an analog signal to a digital signal in an analog-to-digital converter (ADC), is disclosed.
    Type: Grant
    Filed: August 16, 2011
    Date of Patent: November 19, 2013
    Assignee: The Regents of the University of California
    Inventors: Fred Tzeng, Payam Heydari
  • Patent number: 8558727
    Abstract: Compensated current cell to scale switching glitches in digital to analog convertors. A compensated current cell is disclosed that includes first and second switching transistors configured to switch an input current between first and second outputs based on first and second input signals, respectively, a first compensation transistor connected to the first input signal to provide a first compensation current that is connected to the second output, and a second compensation transistor connected to the second input signal to provide a second compensation current that is connected to the first output, the first and second compensation transistors having source terminals that are connected together. In another aspect, switching glitches are scaled based on a size difference between the switching transistors and the compensation transistors.
    Type: Grant
    Filed: May 18, 2011
    Date of Patent: October 15, 2013
    Assignee: QUALCOMM Incorporated
    Inventor: Michael Joseph McGowan
  • Patent number: 8552893
    Abstract: A control system provides a control signal to a nonlinear plant that generates a response signal responsive to the control signal. The control system includes a detector that detects a predetermined value of a plant quantity, valley switching logic, coupled to the detector, to change a state of a plant switch when the plant quantity is minimized, and a pulse-width modulator, coupled to the valley switching logic, to generate a control signal that controls the plant switch. The valley switching logic includes a nonlinear delta-sigma modulator that compensates for an error in a plant response signal by adjusting the duration of an on-time of a plant switch to cause an average value of the plant response signal to converge toward a target signal value.
    Type: Grant
    Filed: November 4, 2011
    Date of Patent: October 8, 2013
    Assignee: Cirrus Logic, Inc.
    Inventors: Mohit Sood, Michael Allan Kost
  • Patent number: 8552897
    Abstract: A reference circuit for use with a charge redistribution analog to digital converter, having a capacitor array, the reference circuit comprising: an input for receiving a signal; an output for supplying a reference voltage to at least one capacitor of the charge redistribution capacitor array; a storage capacitor for storing the reference voltage; a voltage modification circuit for comparing the reference voltage stored on the storage capacitor with the reference signal, and based on the comparison to supply a correction so as to reduce a difference between the reference voltage and the reference signal, the correction being applied during a correction phase; and a first switch for selectively connecting the storage capacitor to the input during an acquisition phase.
    Type: Grant
    Filed: March 22, 2012
    Date of Patent: October 8, 2013
    Assignee: Analog Devices, Inc.
    Inventor: Christopher Peter Hurrell
  • Patent number: 8552895
    Abstract: Disclosed herein is a sigma-delta modulator, including an integration circuit, a first DAC unit, and a second DAC unit. The integration circuit includes first and second terminals, and integrates a voltage supplied via the first terminal. The first DAC unit alternately supplies a first voltage obtained at one end of a first resistor to the first terminal and the second terminal. The second DAC unit alternately supplies a second voltage at the other end of a second resistor to the second terminal or the first terminal. The second DAC unit supplies the second voltage to the second terminal when the first DAC unit supplies the first voltage to the first terminal. The second DAC unit supplies the second voltage to the first terminal when the first DAC unit supplies the first voltage to the second terminal.
    Type: Grant
    Filed: December 22, 2010
    Date of Patent: October 8, 2013
    Assignee: Thine Electronics, Inc.
    Inventor: Tomohiro Nezuka
  • Patent number: 8542139
    Abstract: Provided are a current switch driving circuit generating a signal for driving a current switch, and a digital-to-analog converter using the same. The current switch driving circuit includes a first PMOS transistor in which a source terminal is connected to a power supply terminal, a gate terminal receives an input signal, and a drain terminal outputs a driving signal, an NMOS transistor in which a drain terminal is connected to the drain terminal of the first PMOS transistor, and a gate terminal receives the input signal, a second PMOS transistor in which a source terminal is connected to a source terminal of the NMOS transistor, a gate terminal is connected to a bias voltage terminal, and a drain terminal is connected to a ground terminal, and a control current source allowing the second PMOS transistor to be maintained constantly in an ON state.
    Type: Grant
    Filed: December 2, 2011
    Date of Patent: September 24, 2013
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Min-Hyung Cho, Yi-Gyeong Kim, Jong-Kee Kwon
  • Patent number: 8537040
    Abstract: Systems and methods are disclosed for performing data conversion by matching current sources using a thin oxide device; and minimizing voltage stress on the thin oxide device during operation or power down.
    Type: Grant
    Filed: November 15, 2011
    Date of Patent: September 17, 2013
    Assignee: Integrated Device Technology, Inc.
    Inventors: Mansour Keramat, Yuan-Ju Chao
  • Patent number: 8519876
    Abstract: An ADC with comparing circuit units is provided. Each comparing circuit unit comprises a first resistor, a second resistor, and a CMOS. The first and second resistors provide first and second level voltages, respectively. The base of the PMOS is electrically connected to the power source and the base of the NMOS is connected to the source of the NMOS. The signal input port is located at the gate of the CMOS and receives an analog signal. The first level port of the CMOS is located at the source of the NMOS and receives the first level voltage. The second level port of the CMOS is located at the source of the PMOS and receives the second level voltage. The signal output port of the CMOS is located at the drain and outputs a digital signal.
    Type: Grant
    Filed: March 27, 2012
    Date of Patent: August 27, 2013
    Assignee: National Changhua University of Education
    Inventor: Zhi-Ming Lin
  • Patent number: 8519879
    Abstract: A precision charge dump circuit configured to transfer preset quanta of charge to or from a first capacitor (for example, an integration capacitor in an in-pixel ADC circuit). In one example, the charge dump circuit uses a second capacitor that is pre-charged with the preset quanta of charge to determine the preset value of the quanta of charge, and an amplifier in a voltage-follower mode to cause the charge subtraction or addition.
    Type: Grant
    Filed: April 13, 2012
    Date of Patent: August 27, 2013
    Assignee: Raytheon Company
    Inventor: Martin S. Denham
  • Patent number: 8493251
    Abstract: A digital-to-analog converter (DAC) is disclosed. According to some embodiments of the present disclosure, a DAC may include a plurality of current-steering elements, wherein each respective current-steering element is configured to operate as instructed by a respective calibration signal during respective steps in a calibration cycle, and at least one current-steering element is configured to operate as instructed by a first control signal during at least a first step in which the at least one current-steering element is not being calibrated, and operate as instructed by a second control signal during at least a second step in which the at least one current-steering element is not being calibrated.
    Type: Grant
    Filed: July 28, 2011
    Date of Patent: July 23, 2013
    Assignee: Fujitsu Semiconductor Limited
    Inventor: James J. Riches