Digital To Analog Conversion Patents (Class 341/144)
  • Publication number: 20150070201
    Abstract: Mixed-signal circuitry, comprising: a first switching-circuitry unit for use in an analogue-to-digital converter; and a second switching-circuitry unit for use in a digital-to-analogue converter, wherein: the first switching-circuitry unit is configured to sample an input analogue signal and output a plurality of samples based on a first plurality of clock signals; the second switching-circuitry unit is configured to generate an output analogue signal based on a plurality of data signals and a second plurality of clock signals; and the first and second pluralities of clock signals have the same specifications as one another.
    Type: Application
    Filed: September 12, 2013
    Publication date: March 12, 2015
    Applicant: FUJITSU SEMICONDUCTOR LIMITED
    Inventors: Ian Juso DEDIC, Saul Darzy, Gavin Lambertus Allen
  • Publication number: 20150070202
    Abstract: A switching circuit, comprising: a main switch having a control terminal; and a clock-path portion connected to the control terminal of the main switch to apply a driving clock signal thereto so as to drive the main switch, wherein the circuit is configured to controllably apply a biasing voltage to the clock-path portion so as to bias a voltage level of the driving clock signal as applied to the control terminal of the main switch.
    Type: Application
    Filed: August 29, 2014
    Publication date: March 12, 2015
    Inventors: Ian Juso DEDIC, Gavin Lambertus ALLEN, Saul DARZY
  • Patent number: 8976050
    Abstract: Mixed-signal circuitry, comprising: a first switching-circuitry unit for use in an analog-to-digital converter; and a second switching-circuitry unit for use in a digital-to-analog converter, wherein: the first switching-circuitry unit is configured to sample an input analog signal and output a plurality of samples based on a first plurality of clock signals; the second switching-circuitry unit is configured to generate an output analog signal based on a plurality of data signals and a second plurality of clock signals; and the first and second pluralities of dock signals have the same specifications as one another.
    Type: Grant
    Filed: September 12, 2013
    Date of Patent: March 10, 2015
    Assignee: Fujitsu Semiconductor Limited
    Inventors: Ian Juso Dedic, Saul Darzy, Gavin Lambertus Allen
  • Publication number: 20150061911
    Abstract: Provided are, among other things, systems, apparatuses, methods and techniques for converting a discrete-time quantized signal into a continuous-time, continuously variable signal. An exemplary converter preferably includes: (1) multiple oversampling converters, each processing a different frequency band, operated in parallel; (2) multirate (i.e., polyphase) delta-sigma modulators (preferably second-order or higher); (3) multi-bit quantizers; (4) multi-bit-to-variable-level signal converters, such as resistor ladder networks or current source networks; (5) adaptive nonlinear, bit-mapping to compensate for mismatches in the multi-bit-to-variable-level signal converters (e.g., by mimicking such mismatches and then shifting the resulting noise to a frequently range where it will be filtered out by a corresponding bandpass (reconstruction) filter); (6) multi-band (e.g.
    Type: Application
    Filed: November 10, 2014
    Publication date: March 5, 2015
    Inventor: Christopher Pagnanelli
  • Publication number: 20150061910
    Abstract: Methods and systems for a low input voltage low impedance termination stage for current inputs may comprise, in a semiconductor die, generating an output current proportional to an input signal, where the output current is generated by an output stage that may include a pair of input cascode transistors and at least one pair of stacked output transistors. A source-follower feedback path for the input cascode transistors may include a feedback transistor with its gate terminal coupled to a drain terminal of a first of the input cascode transistors, a drain of the feedback transistor coupled to a supply voltage, and a source terminal of the feedback transistor coupled to a current source that is coupled to ground. A current source may be coupled to the drain of the first of the input cascode transistors. The supply voltage may be coupled to the stacked output transistors via a load resistor.
    Type: Application
    Filed: August 28, 2014
    Publication date: March 5, 2015
    Inventors: Rajesh Zele, Gaurav Chandra
  • Publication number: 20150061908
    Abstract: A digital-to-analog (DAC) element may include a plurality of switches arranged to form two circuit branches between a current source and a first and a second outputs. The first circuit branch may include two switches defining parallel current paths between the current source and the first output terminal. The second circuit branch may include two switches defining parallel current paths between the current source and the second output terminal. A control circuit, responsive to an input signal that selects one of the circuit branches, may provide control signals to close one of switches in the selected circuit branch in a first portion of a clock cycle and to close the other of the switches in the selected circuit branch in a second portion of the clock cycle.
    Type: Application
    Filed: February 12, 2014
    Publication date: March 5, 2015
    Applicant: ANALOG DEVICES TECHNOLOGY
    Inventors: Sanjay RAJASEKHAR, Abhilasha KAWLE, Roberto S. MAURINO, Srikanth NITTALA
  • Publication number: 20150061909
    Abstract: Provided is a system and method for synchronization between digital-to-analog converters (DAC) for high speed signal processing. A synchronization method of a multi-DAC apparatus may include: inputting a clock to a multiplexer (MUX) DAC; dividing the clock into a first clock and a second clock; transferring a phase difference between the first clock and the second clock to a D flip-flop; and synchronizing the first clock and the second clock by processing the phase difference.
    Type: Application
    Filed: June 11, 2014
    Publication date: March 5, 2015
    Inventors: Soo Yeob JUNG, Pan Soo KIM, Joon Gyu RYU, Deock Gil OH
  • Publication number: 20150061905
    Abstract: A method is provided for supplying a customized data converter fabricated from a universal function die. The method initially fabricates a plurality of universal data converter dice. Each universal data converter die is capable of performing a first plurality of data conversion algorithms. After the dice are made, each universal data converter die is tested to verify the performance of the first plurality of data conversion algorithms. Subsequently, a request is received for a customized data converter capable of performing a first data conversion function, which is selected from among the first plurality of data conversion algorithms. The method then fabricates a customized data converter capable of performing the first data conversion function, using a tested universal data converter die. The unselected data converter functions are disabled (not enabled). A configuration interface may be used to enable the requested data conversion function.
    Type: Application
    Filed: November 10, 2014
    Publication date: March 5, 2015
    Inventor: Michael Kappes
  • Patent number: 8970414
    Abstract: Methods, systems, and apparatuses for converting a digital input signal to an analog output signal are disclosed. A first delta-sigma modulator receives a common mode reference signal and generates a common mode control signal. A data delta-sigma modulator receives a digital input signal and generates a modulated digital input signal. A shuffler receives the modulated digital input signal and the common mode control signal and generates a shuffled digital input signal. A digital to analog converter (DAC) has a plurality of tri-level unit DAC elements each receiving a corresponding portion of the shuffled digital input signal as a first input signal, and receiving second and third input signals. The tri-level unit DAC elements have first outputs coupled together generating a first output signal and second outputs coupled together generating a second output signal. An operational amplifier receives the first and second output signals and generates the analog output signal.
    Type: Grant
    Filed: June 28, 2013
    Date of Patent: March 3, 2015
    Assignee: Broadcom Corporation
    Inventors: David Stoops, Min Gyu Kim, Vinod Jayakumar
  • Patent number: 8970639
    Abstract: A two-stage digital-to-analog converter for outputting an analog voltage in response to a M-bit digital input code includes a one-bit serial charge redistribution digital-to-analog converter having a high reference voltage input node for receiving a high reference voltage and a low reference voltage input node for receiving a low reference voltage. A voltage selector sets the high reference voltage and low reference voltage to selected levels depending on at least a portion of the M-bit digital input code.
    Type: Grant
    Filed: August 20, 2010
    Date of Patent: March 3, 2015
    Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventor: Nang-Ping Tu
  • Patent number: 8970573
    Abstract: A display driver maps a selection code (a digital signal) to a reference voltage which is then used to produce a particular intensity of the radiation emitted from a pixel on a display screen (e.g., a LCD display). This mapping may be performed by one or more DACs in the display driver. However, instead of transmitting all of the different possible reference voltages to the DACs, only a subset of the reference voltages are transmitted. Each DAC may include an interpolator circuit that uses the received reference voltages to interpolate the reference voltages that were not transmitted. In this manner, the display driver may still provide the same number of unique reference voltages to a display screen while transmitting fewer reference voltages along the driver's optical channel.
    Type: Grant
    Filed: June 27, 2012
    Date of Patent: March 3, 2015
    Assignee: Synaptics Incorporated
    Inventors: Imre Knausz, Clint Meyer
  • Patent number: 8970758
    Abstract: An image pickup device is provided, capable of complete correction with data of once analog-to-digital conversion, and prevention of excess use of switches and analog devices and/or erroneous correction, including: an image sensor having a plurality of analog-to-digital converters determining conversion results from a digital signal of higher order bit through separate steps of two or more times; a first correction unit which has a correction factor for correcting nonlinear errors of the plurality of analog-to-digital converters so as to adapt to the analog-to-digital converters and corrects a nonlinear error of a digital signal output from respective analog-to-digital converters based on a correction factor corresponding to respective analog-to-digital converters, characterized in that the first correction unit corrects the nonlinear errors after converting the digital signals from the plurality of analog-to-digital converters into a serial output.
    Type: Grant
    Filed: April 26, 2013
    Date of Patent: March 3, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yuichiro Yamashita
  • Patent number: 8970418
    Abstract: The present disclosure discloses a digital-to-analog converter (DAC) design which is suitable for providing a high output power high-speed DAC, e.g., in radio frequency applications. The DAC design utilizes a parallel DAC structure, e.g., having 8 parallel DACs and an aggregate current output, to provide a high and programmable current output (in some implementations, up to 512 mA or more). The parallel DAC structure alleviates the design problems which exist in trying to output a high amount of current using a single DAC. The DAC design further utilizes a hybrid structure which integrates the signal chain for a more reliable system. In some embodiments, the hybrid structure uses a CMOS process for the current sources and switches and a GaAs cascode stage for combining the outputs to optimally leverage the advantages of both technologies. The result is a highly efficient DAC (with peak output power programmable up to 29 dBm or more).
    Type: Grant
    Filed: March 21, 2014
    Date of Patent: March 3, 2015
    Assignee: Analog Devices, Inc.
    Inventors: Bernd Schafferer, Bing Zhao
  • Patent number: 8970411
    Abstract: Traditionally, pipelined continuous-time (CT) sigma-delta modulators (SDM) have been difficult to build due at least in part to the difficulties in calibrating the pipeline. Here, however, a pipelined CT SDM is provided that has an architecture that is conducing to being calibrated. Namely, the system includes a digital filter and other features that can be adjusted to account for input imbalance errors and well as quantization leakage noise.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: March 3, 2015
    Assignee: Texas Instruments Incorporated
    Inventors: Baher S. Haroun, Venkatesh Srinivasan, Patrick Satarzadeh, Marco Corsi
  • Patent number: 8964860
    Abstract: To provide a digital modulator including: a signal adjuster (105) which is provided with a plurality of output lines, and which outputs, to the output line, which corresponds to a range to which a level of an input signal belongs, a signal of a level corresponding to the level of the input signal; a plurality of internal digital modulators (111-1 to 111-N), each of which is provided so as to correspond to each of the plurality of output lines and carries out delta-sigma modulation on the signal of the corresponding output line to output the modulated signal; and an encoder (113) which encodes the plurality of modulated signals respectively outputted by the plurality of internal digital modulators.
    Type: Grant
    Filed: March 13, 2012
    Date of Patent: February 24, 2015
    Assignee: NEC Corporation
    Inventor: Shinichi Hori
  • Patent number: 8963756
    Abstract: A D/A converter according to the present invention includes a wave-form data-array memory means for memorizing a wave-form data array configured of a plurality of digital values, a wave-form output-format data memory means for memorizing wave-form output-format data designating a wave-form output period, a digital value output means for sequentially reading out the digital values for each wave-form output period from the wave-form data-array memory means and outputting the values, and a D/A conversion means for converting the digital values outputted from the digital value output means into analog-data values.
    Type: Grant
    Filed: September 28, 2010
    Date of Patent: February 24, 2015
    Assignee: Mitsubishi Electric Corporation
    Inventors: Atsuko Onishi, Yoshiyuki Kubota
  • Patent number: 8965211
    Abstract: A system and method of digitizing an analog signal without an amplitude channel is disclosed. The system and method includes receiving an analog signal comprising a voltage v(t) and a frequency f1, producing a series of optical pulses at a sampling frequency f2 with a pulsed laser, splitting the series of optical pulses into a first optical signal and an optical reference signal, phase modulating the first optical signal with the analog signal to produce a sampled optical signal such that phase shifts between adjacent samples in the sampled optical signal does not exceed ? radians, and receiving the sampled optical signal and the optical reference signal at a photonic signal processor.
    Type: Grant
    Filed: September 29, 2011
    Date of Patent: February 24, 2015
    Assignee: Rockwell Collins, Inc.
    Inventors: Raymond Zanoni, Kim S. Jepsen, Oliver S. King, Mark A. Laliberte
  • Publication number: 20150048961
    Abstract: The present disclosure discloses a digital-to-analog converter (DAC) design which is suitable for providing a high output power high-speed DAC, e.g., in radio frequency applications. The DAC design utilizes a parallel DAC structure, e.g., having 8 parallel DACs and an aggregate current output, to provide a high and programmable current output (in some implementations, up to 512 mA or more). The parallel DAC structure alleviates the design problems which exist in trying to output a high amount of current using a single DAC. The DAC design further utilizes a hybrid structure which integrates the signal chain for a more reliable system. In some embodiments, the hybrid structure uses a CMOS process for the current sources and switches and a GaAs cascode stage for combining the outputs to optimally leverage the advantages of both technologies. The result is a highly efficient DAC (with peak output power programmable up to 29 dBm or more).
    Type: Application
    Filed: March 21, 2014
    Publication date: February 19, 2015
    Applicant: ANALOG DEVICES, INC.
    Inventors: Bernd SCHAFFERER, Bing ZHAO
  • Publication number: 20150048960
    Abstract: Methods and systems are provided for dynamic power switching in current-steering digital-to-analog converters (DACs). A DAC circuit may be configured to apply digital-to-analog conversions based on current steering, and to particularly incorporate use of dynamic power switching during conversions. The DAC circuit may comprise a main section, which may connect a main supply voltage to a main current source. The main section may comprise a positive-side branch and a negative-side branch, which may be configured to steer positive-side and negative-side currents, such as in a differential manner, to effectuate the conversions. The dynamic power switching may be applied, for example, via a secondary section connecting a main current source in the DAC circuit to a secondary supply voltage. The secondary supply voltage may be configured such that it may be less than the main supply voltage used in driving the current steering in the DAC circuit.
    Type: Application
    Filed: August 8, 2014
    Publication date: February 19, 2015
    Inventor: Jianyu Zhu
  • Patent number: 8957799
    Abstract: A current memory cell includes an amplifier, transistor, first and second capacitors, and first to third switching units. The amplifier includes first to third terminals. The transistor is coupled to first and second nodes, and ground. The first capacitor is coupled between the second node and ground. The second capacitor is coupled between a third node and ground. The first unit couples a current source to the first node during a first period and an output line to the first node during a second period. The second unit couples the first node to the second node during the first period. The third unit couples the first terminal to the second node and couples the second and third terminals to the third node during the first period, and couples the first terminal to the third node and couples the second and third terminals to the second node during the second period.
    Type: Grant
    Filed: March 13, 2014
    Date of Patent: February 17, 2015
    Assignee: Samsung Display Co., Ltd.
    Inventors: Bo-Yeon Kim, Oh-Jo Kwon, Hee-Sun Ahn, Won-Tae Choi
  • Patent number: 8957803
    Abstract: A capacitive voltage divider arrangement includes a first and second voltage divider and a first and second parasitic capacitance formed between the first and second capacitive voltage divider. The first capacitive voltage divider includes: a signal terminal; first capacitance for coupling the terminal to a reference potential; second capacitance; and third capacitance that is coupleable to the reference potential, the second capacitance being coupled in-between the terminal and third capacitance.
    Type: Grant
    Filed: May 3, 2012
    Date of Patent: February 17, 2015
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V.
    Inventors: Harish Balasubramaniam, Harald Neubauer
  • Publication number: 20150041317
    Abstract: A precision bipolar digital-to-analog converter (DAC) that provides a bipolar current output having a substantially fixed zero center point is provided. The DAC includes digital-to-analog converter circuitry configured to provide, responsive to a reference signal indicative of the digital data, a first analog current signal having a first potential and a second analog current signal having a second potential, subtractor circuitry configured to provide a bipolar current signal by subtracting the second analog current signal from the first analog current signal, the bipolar current signal having a zero center point, and first control circuitry electrically coupled to the subtractor circuitry and to the digital-to-analog converter circuitry, and configured to modify the second potential so that the second potential equals the first potential.
    Type: Application
    Filed: August 7, 2014
    Publication date: February 12, 2015
    Applicant: XAGENIC INC.
    Inventor: Wen Chan
  • Publication number: 20150042498
    Abstract: First order gradient errors are canceled with no current source splitting by placing consecutive current sources symmetrically around the center of the array. Consecutive elements that correspond to small input amplitudes (mid-scale codes) make a smaller spatial jump than those correspond to larger signal amplitudes. Both linear and second order gradients are reduced by splitting each current cell into two and placing sub-elements symmetrically with respect to the center of the array to address the linear gradient effect. To address second order gradients, current element placement follows a pattern such that consecutive element pairs are chosen with one of the pair being placed with respect to the zero error contour of the second order gradient so as to have a positive error and the second of the pair being placed so as to have a negative error resulting in reduced second order error accumulation.
    Type: Application
    Filed: August 9, 2013
    Publication date: February 12, 2015
    Applicant: Silicon Laboratories Inc.
    Inventors: Peter Onody, Abdulkerim L. Coban
  • Patent number: 8954363
    Abstract: A digital-to-analogue converter, with application to electronic circuits with neuromorphic architecture, comprises: transistors of identical nominal geometrical characteristics, but of dispersed current-voltage characteristics, wherein when a constant gate-source voltage is applied to the different transistors, a current varying as a function of the dispersion circulates in the transistor; a digital table receiving a digital word and having a selection output selecting, as a function of the word to be converted, a transistor or transistors supplying a current of desired value representing this word in analogue form. The look-up table is loaded as a function of real measured current-voltage characteristics of different transistors of the set, to establish a look-up between words and current values.
    Type: Grant
    Filed: December 4, 2012
    Date of Patent: February 10, 2015
    Assignee: Commissariat a l'Energie Atomique et aux Energies Alternatives
    Inventors: Rodolphe Heliot, Xavier Jehl, Marc Sanquer, Romain Wacquez
  • Patent number: 8947281
    Abstract: Apparatus and methods for digital-to-analog conversion are disclosed. In one embodiment, an electronic system includes a bias circuit and a digital-to-analog converter (DAC) including an input that receives a digital input signal and an output that drives a transmission line. The digital input signal can be used to control a magnitude and polarity of an output current of the DAC. The DAC further includes one or more p-type metal oxide semiconductor (PMOS) termination transistors that receive a first bias voltage from the bias circuit and one or more n-type metal oxide semiconductor (NMOS) termination transistors that receive a second bias voltage from the bias circuit. The bias circuit controls the voltage levels of the first and second bias voltages to control the termination transistors' small signal resistance to actively terminate the DAC's output.
    Type: Grant
    Filed: March 13, 2014
    Date of Patent: February 3, 2015
    Assignee: ClariPhy Communications, Inc.
    Inventors: Morteza Azarmnia, Vadim Gutnik, William Vanscheik
  • Patent number: 8941522
    Abstract: A digital input to a digital-to-analog converter (DAC) is divided into a most significant portion and a lesser significant portion. At least one tap voltage generator generates a plurality of voltages, preferably using a resistor string. A decoder decodes at least one sub-word that forms the lesser significant portion to generate a corresponding at least one control signal. A switching unit accesses voltages generated by the at least one tap voltage generator in response to the at least one control signal. A scaled current generator generates a respective weighted current from each accessed voltage. An output stage combines all the weighted currents with a voltage that is an analog representation of the most significant portion of the digital input to generate an analog approximation of the entire digital input.
    Type: Grant
    Filed: January 23, 2013
    Date of Patent: January 27, 2015
    Assignee: Analog Devices Technology
    Inventor: Italo Carlos Medina Sánchez-Castro
  • Patent number: 8941520
    Abstract: An inverter-driven resistor-ladder digital-to-analog (DAC) converter includes a resistor-ladder network that comprises a resistor for each bit signal of a multi-bit input signal. Each resistor of the resistor-ladder network comprises an input end and an output end. The input end of each resistor is coupled to a corresponding bit signal of the multi-bit input signal, and the output end of each resistor is coupled to an output node of the resistor-ladder network. An output voltage is generated at the output node that is based on the multi-bit input signal. In one exemplary embodiment, the multi-bit input signal is a sigma-delta (??) modulated multi-bit input signal. In another exemplary embodiment, resistance values of the resistors of the resistor-ladder network are related by a binary weighting. In still another exemplary embodiment, resistance values of the resistors of the resistor-ladder network are substantially equal.
    Type: Grant
    Filed: September 30, 2011
    Date of Patent: January 27, 2015
    Assignee: Intel Corporation
    Inventors: Hyung Seok Kim, Yee W. Li, Ashoke Ravi, Hasnain Lakdawala
  • Publication number: 20150014516
    Abstract: A DA converter includes a first DA conversion section for obtaining an analog output signal in accordance with a digital input signal value, and a second DA conversion section for obtaining an analog gain control output signal in accordance with a digital gain control input signal value. In the DA converter, the gain control of the analog output signal generated by the first DA conversion section is performed on the basis of the gain control output signal generated by the second DA conversion section.
    Type: Application
    Filed: January 17, 2014
    Publication date: January 15, 2015
    Applicant: Sony Corporation
    Inventors: Go ASAYAMA, Noriyuki FUKUSHIMA, Yoshikazu NITTA, Yoshinori MURAMATSU, Kiyotaka AMANO
  • Publication number: 20150009058
    Abstract: Embodiments of the disclosed invention address a method, apparatus and computer program product for enabling enhanced transmitter noise shaping. Thereby, a first digital-to-analog conversion is performed on a digital signal resulting in first analog signal, a noise shaping on the digital signal is performed for obtaining a noise shaped signal and performing a second digital-to-analog conversion on the noise shaped signal resulting in a second analog signal, and the first analog signal and the second analog signal are added for obtaining an output signal.
    Type: Application
    Filed: July 2, 2014
    Publication date: January 8, 2015
    Inventors: Markus NENTWIG, Petri Tapani ELORANTA
  • Publication number: 20150009057
    Abstract: A driving circuit includes channels, a positive converting unit, a negative converting unit, an input switch, and an operational amplifier. A first digital data and a second digital data are alternatively transmitted in a first channel and a second channel. The positive converting unit and negative converting unit are respectively disposed in first channel and second channel and convert first digital data and second digital data into a positive analog data and a negative analog data. A first input terminal and a second input terminal of operational amplifier are respectively in first channel and second channel. After input switch respectively transmits positive analog data and negative analog data to first input terminal and second input terminal or to second input terminal and first input terminal, positive analog data and negative analog data are transmitted in a channel of the channels corresponding to entering operational amplifier.
    Type: Application
    Filed: July 1, 2014
    Publication date: January 8, 2015
    Inventors: Yu-Lung Lo, Kuan-Hung Chou, Chien-Ming Chen
  • 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: 8929480
    Abstract: There is provided a transmitter with a small area and low noise. A direct RF modulation transmitter is constituted by an N-number of input signal delay-attached direct RF converters to which an I digital baseband signal is input, an M-number of input signal delay circuit-attached direct RF converters (DDRCs) to which a Q digital baseband signal is input, a Divide-by-2 divider for generating a differential local signal differing in phase by 90 degrees, an output matching circuit, and a delay control circuit for controlling an input data delay amount for the DDRCs. This transmitter sets delay amounts for the DDRCs using the delay control circuit independently. Particularly when N is set to equal M and the same amount of delay is set for N-number of converters corresponding to the I digital baseband signal and the Q digital baseband signal, noise reduction effect in a predetermined frequency band is heightened.
    Type: Grant
    Filed: May 23, 2012
    Date of Patent: January 6, 2015
    Assignee: Asahi Kasei Microdevices Corporation
    Inventor: Shuichi Fukuda
  • 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: 8922412
    Abstract: An apparatus relating generally to digital-to-analog conversion is disclosed. In such an apparatus, a digital-to-analog converter (“DAC”) device includes a source DAC and a sink DAC selectively coupled to one another. The source DAC provides a first bias to the sink DAC in a sink mode, and the sink DAC provides a second bias to the source DAC in a source mode.
    Type: Grant
    Filed: April 30, 2013
    Date of Patent: December 30, 2014
    Assignee: Xilinx, Inc.
    Inventors: Christopher M. Gorman, April M. Graham, John K. Jennings
  • Patent number: 8917195
    Abstract: A system including a first circuit, a second circuit, and a feedback circuit. The first circuit is configured to provide input signals. The second circuit is configured to receive the input signals and provide digital output signals that correspond to the input signals. The feedback circuit includes a chopping circuit, an integrator circuit, and a digital to analog converter circuit. The digital to analog converter circuit is configured to convert an error signal into an analog signal that is received by the second circuit to reduce ripple error.
    Type: Grant
    Filed: June 19, 2012
    Date of Patent: December 23, 2014
    Assignee: Infineon Technologies AG
    Inventors: Mario Motz, Udo Ausserlechner
  • Patent number: 8917196
    Abstract: An A/D converter comprising: a sampling circuit including a continuous section, a sampling and holding section for intermittently sampling an input signal based on an analog signal input from the continuous section to hold and transfer the sampled signal, and a digital section for outputting a signal transferred from the sampling and holding section as a digital signal; and a control circuit for supplying a clock signal in which jitter is not added to the continuous section and supplying a clock signal in which the jitter is added to the sampling and holding section.
    Type: Grant
    Filed: December 27, 2012
    Date of Patent: December 23, 2014
    Assignee: Asahi Kasei Microdevices Corporation
    Inventors: Junya Nakanishi, Yutaka Nakanishi, Seiko Nakamoto
  • Patent number: 8912938
    Abstract: A converter and a method for controlling a converter are disclosed herein, in which the converter includes a converting circuit, a current sensing circuit, a digital-to-analog converting circuit, a slope compensation circuit and a comparator circuit. The slope compensation circuit is independent from the digital-to-analog converting circuit, and the slope compensation circuit exclusively generates an analog slope compensation signal. The comparator circuit compares an analog signal generated by the digital-to-analog converting circuit with the superimposition of the analog slope compensation signal and a current sensing signal generated by the current sensing circuit or compares the current sensing signal with the superimposition of the analog slope compensation signal and the analog signal to generate a comparator output signal for a control operation of the converting circuit.
    Type: Grant
    Filed: January 28, 2014
    Date of Patent: December 16, 2014
    Assignee: Delta Electronics (Shanghai) Co., Ltd.
    Inventors: Hao Lu, Kuang Sheng
  • Patent number: 8912939
    Abstract: Embodiments of the present invention may provide a multi-string DAC with leakage current cancellation. A leakage cancellation circuit may be coupled to output node(s) of the—multi-string DAC. The leakage cancellation circuit may replicate leakage current present at the coupled output node(s) and generate a corresponding complementary signal, a leakage cancellation signal. The leakage cancellation signal may be injected into the coupled output node(s) to cancel (or reduce) the net impact of the leakage current.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: December 16, 2014
    Assignee: Analog Devices Technology
    Inventor: Dennis A. Dempsey
  • Patent number: 8912940
    Abstract: Embodiments of the present invention may provide a string DAC with charge boosting. The string DAC may include multiple strings, such as an MSB DAC and an LSB DAC, for converting a digital word into a corresponding analog voltage. The string DAC may also include a charge boost system to couple a charge into or out of the DAC during a code transition, such as a MSB code transition. The string DAC may operate in a break-before-make connection technique where all relevant connections are substantially open-circuited before new connections are made. Therefore, the charge boost may shorten the settling time of impedance elements in the string DAC between code transitions and may substantially reduce (or eliminate) glitches.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: December 16, 2014
    Assignee: Analog Devices Technology
    Inventor: Dennis A. Dempsey
  • Patent number: 8912937
    Abstract: Highly power efficient transmitter output stage designs are provided. In an embodiment, the probability density function (PDF) of an input signal is divided into a plurality of regions, and samples of the input signal are processed depending on the region of the PDF within which they fall. The PDF can be divided between an inner region corresponding to samples of the input signal that are within a predetermined amplitude range, and outer regions corresponding to samples of the input signal that are outside of the predetermined amplitude range. Samples of the input signal that fall in the inner region are processed by a class A biased amplifier and samples of the input signal that fall in the outer regions are processed by a class B biased amplifier. Output stage designs according to embodiments can be implemented as power amplifiers or power digital-to-analog converters (DACs).
    Type: Grant
    Filed: February 15, 2013
    Date of Patent: December 16, 2014
    Assignee: Broadcom Corporation
    Inventors: Ramon Gomez, Massimo Brandolini, Jiangfeng Wu, Kevin Lee Miller, Hans Eberhart, Tianwei Li
  • Patent number: 8912936
    Abstract: In one aspect, an electrical signal converter is disclosed. The exemplary electrical signal converter may include a plurality of ordered converter elements. Element selection logic may be provided to pseudorandomly select a pointer to a switch matrix, wherein the switch matrix maps converter elements according to a stepwise “delta-two-maximum pattern.” Advantageously, pseudorandom stepwise delta-two-maximum patterns may be applied both to a first order converter, and to a feedback converter for error correction.
    Type: Grant
    Filed: May 30, 2013
    Date of Patent: December 16, 2014
    Assignee: Analog Devices Technology
    Inventors: Trevor Clifford Caldwell, Richard E. Schreier, David Alldred, Wenhua W. Yang
  • Publication number: 20140361913
    Abstract: A communication system including a configurable sample rate converter and a controller is provided. The configurable sample rate converter, configured to convert a digital signal with a first sample rate to a converted signal with a second sample rate, being operable in one of a first configuration and a second configuration. The controller, configured to dynamically control the sample rate converter to operate in one of the first configuration and the second configuration according to at least one condition.
    Type: Application
    Filed: May 21, 2014
    Publication date: December 11, 2014
    Applicant: MStar Semiconductor, Inc.
    Inventors: Ming-Yu Hsieh, Shih-Chieh Yen, Khurram Muhammad
  • Patent number: 8907831
    Abstract: A system includes an N-bit digital-to-analog converter and an M-bit sub-digital-to-analog converter. The N-bit digital-to-analog converter includes 2N resistances connected in series across first and second reference voltages and converts N most significant bits of B bits of data. The M-bit sub-digital-to-analog converter converts M least significant bits of the B bits of data. The M-bit sub-digital-to-analog converter includes a first converter that converts a voltage across one of the 2N resistances to a first current, a current-mode digital-to-analog converter that interpolates the first current and outputs a second current, and a second converter that converts the second current to an output voltage representing the N most significant bits and the M least significant bits of the B bits of data.
    Type: Grant
    Filed: December 20, 2013
    Date of Patent: December 9, 2014
    Assignee: Maxim Integrated Products, Inc.
    Inventor: Syed Amir Aftab
  • Patent number: 8907832
    Abstract: Polarity compensating dual-string digital-to-analog converters (DACs), and related circuits, systems, and methods are disclosed. In embodiments disclosed herein, a secondary voltage divider of a dual-string DAC includes a switch logic unit. The switch logic unit is configured to compensate for polarity changes in the dual-string DAC to maintain monotonicity. Monotonicity means an output voltage of a DAC either increases or stays constant for monotonically increasing functions or either decreases or stays constant for monotonically decreasing functions given an incremental change in a DAC input code. The switch logic unit is configured to compensate for polarity changes in the input voltage from the primary voltage divider to the secondary resistor string. The switch logic unit is configured to select a secondary switch among the plurality of secondary switches in a secondary voltage divider, to divide an input voltage based on a polarity indicator and a DAC input code, to maintain monotonicity.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: December 9, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Burt L. Price, Dhaval R. Shah, Yeshwant Nagaraj Kolla
  • Patent number: 8903092
    Abstract: A system includes a first circuit including a scrambling module that receives N digital data streams and that scrambles the N digital data streams using a scrambling sequence. A data bus receives the N scrambled digital data streams and the scrambling sequence. A second circuit communicates with the data bus and includes a first processing module that processes the N scrambled digital data streams and that outputs M digital data streams, where M and N are integers greater than one. The second circuit includes one or more descrambling and processing modules that receive the M digital data streams, that descramble the M digital data streams based on the scrambling sequence, and that further process the M digital data streams. The second circuit includes a digital to analog converter (DAC) module that receives an output of the one or more descrambling and processing modules.
    Type: Grant
    Filed: June 4, 2010
    Date of Patent: December 2, 2014
    Assignee: Maxim Integrated Products, Inc.
    Inventors: Geir Sigurd Ostrem, Brian Paul Brandt
  • Patent number: 8896757
    Abstract: There is provided a delta-sigma A/D converter including a first integrator, a second integrator located on an output side of the first integrator, a quantizer located on an output side of the second integrator, and a first current D/A converter receiving an output of the quantizer and providing a negative feedback signal to an input side of the quantizer.
    Type: Grant
    Filed: August 7, 2013
    Date of Patent: November 25, 2014
    Assignee: Sony Corporation
    Inventor: Tomohiro Matsumoto
  • Patent number: 8896471
    Abstract: Provided are, among other things, systems, apparatuses, methods and techniques for converting a discrete-time quantized signal into a continuous-time, continuously variable signal. An exemplary converter preferably includes: (1) multiple oversampling converters, each processing a different frequency band, operated in parallel; (2) multirate (i.e., polyphase) delta-sigma modulators (preferably second-order or higher); (3) multi-bit quantizers; (4) multi-bit-to-variable-level signal converters, such as resistor ladder networks or current source networks; (5) adaptive nonlinear, bit-mapping to compensate for mismatches in the multi-bit-to-variable-level signal converters (e.g., by mimicking such mismatches and then shifting the resulting noise to a frequently range where it will be filtered out by a corresponding bandpass (reconstruction) filter); (6) multi-band (e.g.
    Type: Grant
    Filed: October 8, 2012
    Date of Patent: November 25, 2014
    Assignee: Syntropy Systems, LLC
    Inventor: Christopher Pagnanelli
  • Patent number: 8896478
    Abstract: A successive approximation analog-to-digital converter (SAR ADC) includes a capacitor array and a comparator. The capacitor array has M capacitors which are arranged to perform capacitor switching operations sequentially, wherein a sum of capacitance values of the M capacitors is equal to (2N?1) unit capacitors, M>N, and M and N are both positive integers. The comparator is arranged for comparing an output of the capacitor array and an analog input sequentially.
    Type: Grant
    Filed: August 5, 2013
    Date of Patent: November 25, 2014
    Assignee: Realtek Semiconductor Corp.
    Inventors: Jen-Huan Tsai, Po-Chiun Huang
  • Patent number: RE45282
    Abstract: An image sensor system using offset analog to digital converters. The analog to digital converters require a plurality of clock cycles to carry out the actual conversion. These conversions are offset in time from one another, so that at each clock cycle, new data is available. A system includes a CMOS active pixel image sensor having an array for photoreceptors to convert an image into an analog signal. The CMOS image sensor converts the analog signal into a digital signal using a pipelined analog to digital converter.
    Type: Grant
    Filed: January 24, 2012
    Date of Patent: December 9, 2014
    Assignee: Round Rock Research, LLC
    Inventors: Eric R. Fossum, Sandor L. Barna