Digital To Analog Conversion Patents (Class 341/144)
  • 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: 8896473
    Abstract: A digital-to analog-converter (DAC) has a MSB resistor ladder with a plurality of series connected resistors, wherein the MSB resistor ladder is coupled between a first and second reference potential, a LSB resistor ladder with a plurality of series connected resistors, and a plurality of switching units for connecting one of the series connected resistors of the MSB resistor ladder with the LSB resistor ladder, wherein each switching unit has a first switch for connecting a first terminal of an associated MSB resistor with a first terminal of the LSB resistor ladder and a second switch for connecting a second terminal of the associated MSB resistor with a second terminal of the LSB resistor ladder and wherein each switch is configured form a resistor of similar value of the resistors of the LSB resistor ladder when switched on.
    Type: Grant
    Filed: May 20, 2013
    Date of Patent: November 25, 2014
    Assignee: Microchip Technology Incorporated
    Inventor: Gregory Dix
  • Patent number: 8896472
    Abstract: An N-bit digital-to-analog converter (DAC) includes N input stages each of which generates the same amount of current and includes a pair of similarly sized transistor switches responsive to differential bits. The 2M?1 input stages associated with the M most significant bits of the DAC are connected in parallel and deliver their currents differentially to the DAC's current summing nodes. Each of the remaining (N?M) stages includes a resistive network that supplies a current defined by a binary weight of the stage's bit position within the DAC. The (N?M) stages deliver their currents to the current summing nodes differentially. The DAC further includes an impedance attenuator adapted to maintain the impedance of the current summing nodes and the voltage difference between the current summing nodes within a range defined by a gain of a differential amplifier disposed in the impedance attenuator.
    Type: Grant
    Filed: March 8, 2013
    Date of Patent: November 25, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Dongwon Seo, Sang Min Lee
  • Publication number: 20140340385
    Abstract: Provided first and second reference voltage set wherein the first reference voltage set includes a part or all of reference voltages of the second reference voltage set, and a decoder including first and second sub-decoder sections that select Q reference voltages from first and second reference voltage sets according to upper bits of the input digital signal and transfer the so selected reference voltages to the first to Qth nodes, and third and fourth sub-decoder sections that select first and second voltages from the Q reference voltages transferred to the first to Qth nodes according to lower bits of the input digital signal and transfer the so selected voltages to the first to Pth nodes. The first and third sub-decoder sections are made up of first conductivity type transistors, whilst the second and fourth sub-decoder sections are made up of second conductivity type transistors.
    Type: Application
    Filed: July 31, 2014
    Publication date: November 20, 2014
    Applicant: Renesas Electronics Corporation
    Inventor: Hiroshi TSUCHI
  • Publication number: 20140340251
    Abstract: A digital to analog converter includes a first switch, a second switch, and a driver module. The first switch includes a first differential pair of transistors connected to first inputs to receive digital data for conversion to analog data based on a clock signal output by a clock, and first outputs to output the analog data. The second switch includes second and third differential pairs of transistors connected to second inputs and the first outputs. The driver module drives one of the second inputs based on the digital data and toggles the second switch during a first cycle of the clock signal if the first switch is not toggled during the first cycle of the clock signal.
    Type: Application
    Filed: July 31, 2014
    Publication date: November 20, 2014
    Inventor: Jerzy Antoni Teterwak
  • Patent number: 8890736
    Abstract: A signal mixing circuit which mixes input signal(s) and oscillation signal(s) by mixer block(s) to provide a mixed signal. Each mixer block includes a summing node and a circuit unit; the summing node is arranged to provide a sum signal by summing an input signal and an oscillation signal, and the circuit unit is arranged to alternate between a first state and a second state in response to alternating of the oscillation signal; wherein the circuit unit is arranged to provide driving contribution to the mixed signal in response to the sum signal during the first state, and to stop providing driving contribution during the second state. An associated converter, e.g., a digital-to-analog converter, is also disclosed.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: November 18, 2014
    Assignee: MEDIATEK Inc.
    Inventors: Wei-Hao Chiu, Ang-Sheng Lin
  • Patent number: 8890731
    Abstract: The present invention provides a conversion circuit including: an inputting unit, a DAC connected to the inputting unit, an ADC connected to an output end of the DAC, and a comparing unit connected to an output end of the ADC. The comparing unit compares a test code set output by the ADC with a second standard test code set, and if the comparison result is in a preset error range, notify a test data collecting unit; otherwise, output the comparison result to a correcting unit. The correcting unit obtains a complementary code set according to the comparison result, and output the complementary code set to the inputting unit, so that the inputting unit updates the standard test code set according to the complementary code set and obtains the updated first standard test code set. The test data collecting unit obtains a voltage value of an input end of the ADC.
    Type: Grant
    Filed: November 19, 2013
    Date of Patent: November 18, 2014
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Peter Kaiping Deng, Tao Xiong
  • Patent number: 8890737
    Abstract: Described are apparatuses and methods of current balancing, current sensing and phase balancing, offset cancellation, digital to analog current converter with monotonic output using binary coded input (without binary to thermometer decoder), compensator for a voltage regulator (VR), etc. In one example, an apparatus comprises: a plurality of inductors coupled to a capacitor and a load; a plurality of bridges, each of which is coupled to a corresponding inductor from the plurality of inductors; and a plurality of current sensors, each of which is coupled to a bridge to sense current through a transistor of the bridge.
    Type: Grant
    Filed: June 28, 2013
    Date of Patent: November 18, 2014
    Assignee: Intel Corporation
    Inventors: Gerhard Schrom, J. Keith Hodgson, Alexander Lyakhov, Chiu Keung Tang, Narayanan Raghuraman, Narayanan Natarajan
  • Patent number: 8884797
    Abstract: A method for converting a multi-bit digital value to an analog value. The method includes, in a first conversion cycle, converting a first set of digital bits to a first analog voltage using passive charge-sharing. The method also includes, in a second conversion cycle, converting a second set of digital bits to a second analog voltage added to the first analog voltage using active charge-sharing. The first set of digital bits and the second set of digital bits are different bits of the multi-bit digital value.
    Type: Grant
    Filed: February 25, 2011
    Date of Patent: November 11, 2014
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Yung-Chow Peng, Jui-Cheng Huang, Ching-Ho Chang, Nang Ping Tu
  • Patent number: 8884798
    Abstract: Systems and techniques for performing binary divarication digital-to-analog conversion are described. A described converter includes voltage range adjusters arranged in series to convert a digital sequence to an analog representation, each of the adjusters being responsive to a respective bit of the digital sequence, and a combiner. The first adjuster produces first high and low output voltages based on first high and low input voltages and a most significant bit value of the digital sequence. The last adjuster produces last high and low output voltages based on last high and low input voltages and a least significant bit value of the digital sequence. The last high and low input voltages are responsive to the first high and low output voltages as modified by any of zero or more intermediate voltage range adjusters. The combiner produces an analog output signal based on the last high and low output voltages.
    Type: Grant
    Filed: November 30, 2012
    Date of Patent: November 11, 2014
    Assignee: Atmel Corporation
    Inventor: Jed Griffin
  • Patent number: 8884799
    Abstract: Dual-string digital-to-analog converters (DACs), and related circuits, systems, and methods are disclosed. In embodiments disclosed herein, a primary voltage divider of the dual string-DAC is comprised of at least one adjusting circuit. The adjusting circuit is configured to maintain the ideal voltage of a selected resistor node pair across a secondary voltage divider circuit in response to a primary switch unit selecting a selected resistor node pair. In this manner, impedance isolation is not required between a primary voltage divider and the secondary voltage divider circuit of the dual-string DAC. As a result, as non-limiting examples, the area on an integrated circuit (IC) for a dual-string DAC may be decreased, power consumption of the DAC may be decreased, and/or the dual-string DAC may have increased performance by not requiring a settling time.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: November 11, 2014
    Assignee: QUALCOMM Incroporated
    Inventors: Burt L. Price, Dhaval R. Shah, Yeshwant Nagaraj Kolla
  • Publication number: 20140328429
    Abstract: One example described herein relates to a digital to analog converter (DAC). The DAC includes a digital signal input configured to receive a multi-bit digital input signal, and a plurality of unit cells arranged in rows and columns. A row decoder and a column decoder provide respective control signals to respective rows and respective columns to selectively couple a number of the unit cells to an output of the DAC. The number of unit cells which are coupled to the output by the control signals is dependent on the multi-bit digital input signal. At least one of the control signals is modulated based on a local oscillator signal.
    Type: Application
    Filed: July 21, 2014
    Publication date: November 6, 2014
    Inventors: Franz Kuttner, Michael Fulde
  • Publication number: 20140327561
    Abstract: Disclosed are systems, devices and methods related to mixed mode time interleaved digital-to-analog converters (DACs). In some embodiments, such DACs can be utilized for radio-frequency (RF) applications. In some embodiments, a DAC for RF applications can include a first circuit configured to receive a digital signal and perform a first operation to yield an increased bandwidth of the DAC. The DAC can further include a second circuit configured to perform a second operation on the digital signal to yield an analog signal representative of the digital signal. The second circuit can be further configured to reduce or remove an image within the increased bandwidth.
    Type: Application
    Filed: May 1, 2014
    Publication date: November 6, 2014
    Inventor: Stephane Richard Marie WLOCZYSIAK
  • Patent number: 8878709
    Abstract: Disclosed herein is a semiconductor integrated circuit including: line buffers; an alpha channel first selector; an alpha channel digital-to-analog converter; a beta channel digital-to-analog converter; a redundant digital-to-analog converter; an alpha channel second selector; a beta channel second selector; an alpha channel amplifier; and a beta channel amplifier.
    Type: Grant
    Filed: June 16, 2010
    Date of Patent: November 4, 2014
    Assignee: Sony Corporation
    Inventors: Kenji Hyodo, Takashi Ichirizuka, Takuya Kimoto, Minoru Togo
  • Publication number: 20140320327
    Abstract: A system for scalable voltage ramp control for power supply systems. A system may comprise at least power supply circuitry, digital-to-analog (D/A) converter circuitry and a controller. The power supply circuitry may be configured to output a voltage to a load based on an input voltage provided by the D/A converter. The controller may be configured to control the D/A converter (e.g., to cause the D/A converter to provide the input voltage to the power supply circuitry) using a large range voltage ramp-up or a small range voltage ramp-up. Utilization of the large range voltage ramp-up or the small range voltage ramp-up by the controller may be based on, for example, a threshold voltage.
    Type: Application
    Filed: April 25, 2013
    Publication date: October 30, 2014
    Applicant: FAIRCHILD SEMICONDUCTOR CORPORATION
    Inventors: Siqiang Fan, Andrew Kameya, Bin Zhao
  • Patent number: 8872686
    Abstract: The present disclosure relates to a method and architecture to minimize a transient glitch within a current digital-to-analog converter (DAC) comprising an array of identical current unit cells. The current DAC is configured with individual column decoders for even and odd rows of current unit cells, thus allowing for independent control of adjacent rows. The even row and odd row column decoders further comprise thermal decoders with coupled timing encoding which establishes synergy between an adjacent pair of rows. As current units cells within an active row are activated across the row by a counting up of a first column decoder, the current units cells within a next row adjacent the active row are returned to an initial state of the active row by counting down in a second column decoder. Other devices and methods are also disclosed.
    Type: Grant
    Filed: April 8, 2013
    Date of Patent: October 28, 2014
    Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Kuo-Yu Chou, Wei Lun Tao, Shang-Fu Yeh, Yi-Che Chen, Calvin Yi-Ping Chao
  • 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: 8872687
    Abstract: A digital to analog converting method insensitive to code-dependent distortions is implemented by a digital to analog converter (DAC) having a plurality of unit current sources. A plurality of binary-weighted input codes are received by the DAC and rotated to generate dynamic element matched (DEM) encoded signals. Between the adjacent DEM encoded signals is a purposely added pre-determined return-to-zero (RTZ) code. When the DAC generates analog outputs according to the alternately received DEM encoded signals and the RTZ codes, a zero-voltage phase during the level transition of the analog outputs is obtained by the RTZ codes. With the DEM encoded signals and the RTZ codes, each level transition is independent. Furthermore, code-dependent problems such as mismatch- and transient-related distortion are mitigated by the DEM encoded signals.
    Type: Grant
    Filed: September 12, 2013
    Date of Patent: October 28, 2014
    Assignee: National Cheng Kung University
    Inventors: Wei-Te Lin, Hung-Yi Huang, Tai-Haur Kuo
  • Patent number: 8872691
    Abstract: A method of operating an analog to digital converter (ADC) comprises comparing an analog input signal to a reference signal, using a comparator, and generating a comparator output according to the comparison, storing the comparator output in at least one memory unit, monitoring the stored comparator output to determine whether a difference between the analog input signal and the reference signal is within a predetermined range, and detecting a metastability error upon determining that the difference between the analog input signal and the reference signal is within a predetermined range.
    Type: Grant
    Filed: May 3, 2013
    Date of Patent: October 28, 2014
    Assignee: Keysight Technologies, Inc.
    Inventor: Dusan Stepanovic
  • Patent number: 8866658
    Abstract: A resistor string digital-to-analog converter includes a high-order resistor string, first high-order switches, a high-order decoder, a low-order decoder, and a conversion unit. The high-order resistor string includes a plurality of voltage acquisition points that are coupled through unit resistors. The high-order decoder generates a first high-order control signal in accordance with a high-order bit value, and operates in accordance with the first high-order control signal to bring into conduction a first high-order switch coupled to a pair of voltage acquisition points adjacent to each other through one or more voltage acquisition points. The low-order decoder generates a low-order control signal for controlling the conversion unit. The conversion unit divides a pair of high-order analog voltages output from a pair of voltage acquisition points.
    Type: Grant
    Filed: June 21, 2012
    Date of Patent: October 21, 2014
    Assignee: Renesas Electronics Corporation
    Inventor: Koji Hirai
  • Patent number: 8866656
    Abstract: Hybrid digital-to-analog converter and method thereof are provided. The hybrid digital-to-analog converter (DAC) includes a data processor, at least one first type DAC, at least one second type DAC, and an output circuit. The data processor processes an input digital signal to output at least one of first and second digital signals which are related to a higher bit portion and a lower bit portion of the input digital signal, respectively. If the data processor outputs the first digital signal to the first type DAC, the first type DAC converts the first digital signal. The at least one second type DAC receives and converts the second digital signal outputted from the data processor. The output circuit receives at least one output signal of the first and the second type DACs to output an output analog signal.
    Type: Grant
    Filed: December 6, 2013
    Date of Patent: October 21, 2014
    Assignee: Realtek Semiconductor Corp.
    Inventors: Ming-Cheng Chiang, Li-Lung Kao
  • Patent number: 8866650
    Abstract: A circuit for testing digital-to-analog (DAC) and analog-to-digital converters (ADC) is provided. The circuit applies a code pattern having a plurality of sequential values to the digital to analog converter. A plurality of built-in test switches (BTS) couple at least one tap voltage from the DAC to a test bus and to the ADC as a variable reference input voltage. In one form, the circuit uses incremental digital codes to test for defects in a resistor string, a switch array, and a decode logic that form part of the DAC. In another form, the circuit uses the tap voltages from the DAC to test the comparators that form part of the ADC. Instead of performing time-consuming analog to digital conversions, the functionality of the above mentioned circuitry is tested by varying the code pattern around a reference point and by selecting the appropriate combination of BTS switches.
    Type: Grant
    Filed: December 7, 2011
    Date of Patent: October 21, 2014
    Assignee: Intel Corporation
    Inventors: Stephen J. Spinks, Andrew Talbot, Colin Mair
  • Patent number: 8866657
    Abstract: An apparatus of a Digital-to-Analog Converter (DAC) is provided. The apparatus includes a logic circuit for performing a logical operation based on a combination of bit values b0 through bN-1 of a digital code, and a plurality of switches for controlling an output state of a plurality of current cells based on an output of the logical operation, wherein the plurality of the current cells respectively output currents under a control of respective ones of the plurality of switches.
    Type: Grant
    Filed: December 13, 2012
    Date of Patent: October 21, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jong-Woo Lee
  • Patent number: 8860597
    Abstract: Digital-to-analog converter circuitry is described. The digital-to-analog converter circuitry includes a plurality of weighted resistance elements. A first weighted resistance element includes a switch coupled to a reference voltage. The first weighted resistance element also includes a T-network coupled to the switch. The T-network approximately equalizes a first response speed of the first weighted resistance element with a response speed of a differently weighted resistance element.
    Type: Grant
    Filed: July 3, 2012
    Date of Patent: October 14, 2014
    Assignee: QUALCOMM Incorporated
    Inventor: Matthew D. Sienko
  • Patent number: 8860594
    Abstract: Systems and methods for communicating digital data associated with amplitudes and phases of a virtual periodic waveform having a designated period between components connected by n conductors include, in one embodiment, circuitry that converts a first amplitude and a first phase to a first corresponding voltage or current and applies the first corresponding voltage or current to a first one of the plurality of conductors, and converts the first amplitude and the first phase to (n?1) corresponding voltages or currents based on amplitudes of the periodic waveform phase shifted by about m*(360/n) relative to the first phase where m is indexed from one to (n?1) and applies each corresponding voltage or current to an associated conductor of the plurality of conductors. The systems and methods are particularly suited for reducing the number of conductors to obtain a desired I/O data rate/throughput for integrated circuit chips and wired networks.
    Type: Grant
    Filed: May 17, 2012
    Date of Patent: October 14, 2014
    Assignee: Brilliant Points, Inc.
    Inventor: Karl Christopher Hansen
  • Patent number: 8860595
    Abstract: A system for scalable voltage ramp control for power supply systems. A system may comprise at least power supply circuitry, digital-to-analog (D/A) converter circuitry and a controller. The power supply circuitry may be configured to output a voltage to a load based on an input voltage provided by the D/A converter. The controller may be configured to control the D/A converter (e.g., to cause the D/A converter to provide the input voltage to the power supply circuitry) using a large range voltage ramp-up or a small range voltage ramp-up. Utilization of the large range voltage ramp-up or the small range voltage ramp-up by the controller may be based on, for example, a threshold voltage.
    Type: Grant
    Filed: April 25, 2013
    Date of Patent: October 14, 2014
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Siqiang Fan, Andrew Kameya, Bin Zhao
  • Publication number: 20140300501
    Abstract: Aspects of a method and system for data converters having a transfer function with multiple operating zones. In some embodiments, an operating zone of the multiple operating zones is characterized by more stringent performance criteria than the other operating zones. Thus, such data converters may receive an input signal and generate an output signal from the input signal per the transfer function and the more stringent performance criteria in the appropriate operating zone.
    Type: Application
    Filed: April 7, 2014
    Publication date: October 9, 2014
    Applicant: Maxlinear, Inc.
    Inventor: Curtis Ling
  • Publication number: 20140301253
    Abstract: DEM circuit (130) includes a switch (131) configured to receive an N-bit digital input signal (SD1) and shift bit positions of the digital input signal (SD1) based on a switch control signal (SC) in a circulating pattern to output the digital input signal (SD1) as an N-bit digital output signal (SD2), where N is an integer greater than or equal to 2, and a switch control signal generation circuit (132) including a plurality of pointers which move in an identical direction based on a predetermined rule, and configured to generate the switch control signal (SC), each time when the digital input signal (SD1) is input to the switch (131), by using the pointers in a predetermined order.
    Type: Application
    Filed: June 19, 2014
    Publication date: October 9, 2014
    Inventors: Koji OBATA, Kazuo MATSUKAWA, Yosuke MITANI
  • Patent number: 8855579
    Abstract: A method may include measuring a frequency difference between an actual frequency and an expected frequency associated with a frequency control calibration signal value for each of a plurality of frequency control calibration signal values during a calibration phase. The method may additionally include generating integral non-linearity compensation values based on the frequency differences measured The method may further include generating the applied frequency control signal based on a frequency control calibration signal value received by the digital-to-analog converter during the calibration phase. The method may also include generating a compensated frequency control signal value based on a frequency control signal value received by the integral non-linearity compensation module and an integral non-linearity compensation value associated with the frequency control signal value during an operation phase of the wireless communication element.
    Type: Grant
    Filed: June 6, 2012
    Date of Patent: October 7, 2014
    Assignee: Intel IP Corporation
    Inventors: David Harnishfeger, Kristopher Kaufman
  • Patent number: 8854242
    Abstract: A RF digital to analog converter has a first capacitor arrangement, a first common node, and a first controller. The first capacitor arrangement has multiple switchable capacitor paths arranged in parallel. Respective switchable capacitor paths have a switchable element and a capacitor coupled in series. The first common node is connected to the multiple switchable capacitor paths. The first controller receives a baseband signal having an in-phase component and a quadrature component, and a local oscillator (LO) signal having an in-phase LO signal and a quadrature LO signal. The first controller combines the in-phase component and the in-phase LO signal to obtain a first in-phase modulation signal and combines the quadrature component and the quadrature LO signal to obtain a first quadrature modulation signal. The first controller controls the multiple switchable capacitor paths of the first capacitor arrangement with the first in-phase modulation signal and/or the first quadrature modulation signal.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: October 7, 2014
    Assignee: Intel Mobile Communications GmbH
    Inventors: Bernd-Ulrich Klepser, Franz Kuttner
  • Patent number: 8847806
    Abstract: One example described herein relates to a digital to analog converter (DAC). The DAC includes a digital signal input configured to receive a multi-bit digital input signal, and a plurality of cells arranged in rows and columns. Each cell includes a current source. A row decoder and a column decoder provide respective control signals to respective rows and respective columns to selectively couple a number of the current sources to an output of the DAC. The number of current sources which are coupled to the output by the control signals is dependent on the multi-bit digital input signal. At least one of the control signals is modulated based on a local oscillator signal.
    Type: Grant
    Filed: November 29, 2012
    Date of Patent: September 30, 2014
    Assignee: Intel Mobile Communications GmbH
    Inventors: Franz Kuttner, Michael Fulde
  • Patent number: 8847808
    Abstract: A biasing circuit facilitates process, temperature, and voltage insensitive operation of a circuit block. The biasing circuit may include a replicate circuit corresponding to the circuit block. The replicate circuit may be a low complexity version of the circuit block that includes selected process, temperature, or voltage sensitive components of the circuit block. The biasing circuit enforces bias conditions on the circuit block that are informed by the response of the replicate circuit to variations in process, temperature, and voltage.
    Type: Grant
    Filed: June 10, 2013
    Date of Patent: September 30, 2014
    Assignee: Broadcom Corporation
    Inventors: Hongwu Chi, Michael Ming Lee
  • Patent number: 8847807
    Abstract: Embodiments of the present disclosure may provide a switching scheme for tri-level unit elements with ISI mitigation. A tri-level unit element may include a first and second current source and a plurality of switches arranged to form three circuit branches between the first and the second current source. The first circuit branch may include two switches connected in parallel between the first current source and a first output terminal and two switches connected in parallel between the second current source and the first output terminal. The second circuit branch may include two switches connected in parallel between the first current source and a second output terminal and two switches connected in parallel between the second current source and the second output terminal. The third circuit branch may include switches to couple the first current source and the second current source to a dump node.
    Type: Grant
    Filed: March 8, 2013
    Date of Patent: September 30, 2014
    Assignee: Analog Devices, Inc.
    Inventors: Abhishek Bandyopadhyay, Paul A. Baginski
  • Patent number: 8847801
    Abstract: Circuits, methods, non-transitory storage media can be configured to reduce calibration errors in a signal converter. A digital-to-analog converter can include a calibration circuit configured to calibrate a digital-to-analog converter (DAC) bit element using a residual error from a previously calibrated digital-to-analog converter (DAC) bit element. The residual error can be stored in memory.
    Type: Grant
    Filed: February 27, 2013
    Date of Patent: September 30, 2014
    Assignee: QUALCOMM Incorporated
    Inventor: Tongyu Song
  • Patent number: 8849219
    Abstract: In general, according to one embodiment, a DA converter configured to convert a digital signal comprising n (n>1) bits to an analog current to output the analog current from an output terminal, includes n voltage-current converters. Each of them corresponds to each bit of the digital signal and is configured to generate a current depending on the corresponding bit. A k-th (k is an integer of 0 to n?1) voltage-current converter includes a first transistor whose threshold voltage is adjustable. The first transistor includes a semiconductor substrate, a first diffusion region, a second diffusion region, an insulating film, a charge accumulating film, and a gate.
    Type: Grant
    Filed: August 30, 2012
    Date of Patent: September 30, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Jun Deguchi, Shouhei Kousai, Yousuke Hagiwara, Masamichi Suzuki, Atsuhiro Kinoshita, Takao Marukame
  • Patent number: 8847803
    Abstract: Digital input words are received in parallel by a parallel digital-to-digital sigma-delta modulator. Error words corresponding to quantization error are added in parallel to the input words to form encoded data words. The encoded data words are quantized into parallel output words and the error words resulting from such quantization are distributed across parallel modulator stages to effect a predetermined quantization error spectral distribution. The quantized output words are output in parallel.
    Type: Grant
    Filed: May 30, 2012
    Date of Patent: September 30, 2014
    Assignee: MStar Semiconductor, Inc.
    Inventors: Zhongxuan Zhang, Bernard Ginetti
  • Publication number: 20140285369
    Abstract: A multi-string DAC is described and comprises at least two DAC stages. Each DAC stage comprises a string of impedance elements and a switching network. A control loop is provided to control the Ron of the switching network and provide code dependent control of switches in a DAC switching network.
    Type: Application
    Filed: March 14, 2014
    Publication date: September 25, 2014
    Applicant: ANALOG DEVICES TECHNOLOGY
    Inventor: Dennis A. Dempsey
  • Patent number: 8842033
    Abstract: A predistortion generator includes a sample input, a summing circuit to output predistorted samples to a DAC, and distortion term processors, each including a product generator and a FIR filter in tandem. The distortion term processors include a second-order and/or a third-order distortion term processor. In the second-order distortion term processor, the product generator generates a product of only two samples corresponding to a current sample as a respective second-order distortion term that is filtered by the FIR filter thereof using a respective FIR filter characteristic. In the third-order distortion term processor, the product generator generates a product of only three samples corresponding to the current sample as a respective third-order distortion term that is filtered by the FIR filter thereof using a respective FIR filter characteristic. The FIR filter characteristics of FIR filters are configured to reduce distortion in a designated Nyquist zone.
    Type: Grant
    Filed: September 30, 2013
    Date of Patent: September 23, 2014
    Assignee: Agilent Technologies, Inc.
    Inventor: Valentin Abramzon
  • Patent number: 8842032
    Abstract: A method and circuit to perform noise shaped splitting of a digital input signal may include using multiple layers to process the input signal. In the first layer, the most significant bits of the input signal may be distributed to a plurality of branches. Dynamic element matching may be performed using the least significant bits of the input signal. Based on the results of the dynamic element matching, values may be added to the plurality of branches. If there is insufficient data activity, dynamics enhancement may be performed to increase the data activity. The output signals of each of the plurality of branches in the first layer may be provided to a second layer, in which these steps can be repeated on each of the output signals. The outputs of the second layer may be provided to a plurality of three level unit elements.
    Type: Grant
    Filed: February 22, 2013
    Date of Patent: September 23, 2014
    Assignee: Analog Devices, Inc.
    Inventors: Khiem Quang Nguyen, Robert Adams
  • Patent number: 8842029
    Abstract: The invention comprises sample-and-hold circuit and digital-to-analog converter into a differentially operational unit. In analog-to-digital conversion unit, on the premise of fixed or non-fixed quantization error, analog-to-digital converter dynamically adjusts number of bits solved or size of quantized step according to the magnitude of differential voltage between sampled input signal and previously quantized input signal, thus this invention can reduce the non-necessary power consumption from redundant code and overload of input signal. Differentially operational unit and analog-to-digital unit share the same capacitor array which has binary-weighted arrangement to reduce circuit complexity and area.
    Type: Grant
    Filed: March 7, 2013
    Date of Patent: September 23, 2014
    Assignee: National Chiao Tung University
    Inventors: Chun-Yu Wu, Yuan-Fu Lyu
  • Patent number: 8842028
    Abstract: The present invention relates to Digital-to-Analog conversion in the optical or photonic domain. The present invention provides a digital-to-analog converter (DAC) (100) arranged to receive an N-bit digital optical signal (105) and to process the N-bit digital optical signal to generate an analog optical signal (110). The DAC comprises a photonic circuit (120a, 120b) arranged to adjust the amplitude of each bit of the N-bit digital optical signal dependent on the amplitudes of at least one of the other bits of the N-bit digital optical signal. The amplitudes are adjusted using a non-linear optical effect in order to generate respective outputs for each bit. The DAC also comprises a photonic combiner (145) arranged to combine the outputs for each bit to generate the analog output signal (110).
    Type: Grant
    Filed: February 16, 2009
    Date of Patent: September 23, 2014
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Claudio Porzi, Antonella Bogoni, Luca Poti
  • Patent number: 8842027
    Abstract: A method for evaluating capacitor weighting of an analog-to-digital (ADC) is provided. An equivalent weighting value of each composed capacitor in each sub-capacitor-array may be obtained by adding the switch device to the ADC which enables each sub-capacitor-array in a digital-to-analog (DAC) to be measured by each other. The ADC can calculate and then obtain a correct digital output by using the calibrated equivalent weighting and successive approximation result of each input signal.
    Type: Grant
    Filed: March 18, 2013
    Date of Patent: September 23, 2014
    Assignee: Industrial Technology Research Institute
    Inventors: Xuan-Lun Huang, Hao-Jen Lin, Jiun-Lang Huang
  • Patent number: 8842034
    Abstract: A resistor network implemented in an integrated circuit includes a first plurality of interconnect traces coupled in series at a first plurality of nodes; a first plurality of switches coupled between the first plurality of nodes and an output node; a second plurality of interconnect traces coupled in series at a second plurality of nodes; and a second plurality of switches coupled between the second plurality of nodes and the output node, wherein a voltage at the output node is generated in response to a resistance of the resistor network based upon a configuration of the first plurality of switches and the second plurality of switches.
    Type: Grant
    Filed: February 6, 2013
    Date of Patent: September 23, 2014
    Assignee: Xilinx, Inc.
    Inventor: Jingfeng Gong
  • Patent number: 8842030
    Abstract: A sigma-delta analog-to-digital converter includes an input transconductance stage that provides an analog input current proportional to an analog input voltage and a current summing stage that generates an analog error signal corresponding to a difference between the analog input current and a feedback current. The sigma-delta analog-to-digital converter also includes a forward signal path that processes the analog error signal to provide a digital output signal corresponding to the analog input voltage. Additionally, the sigma-delta analog-to-digital converter includes a feedback path that includes a current steering digital-to-analog converter having both sourcing and sinking current sources, wherein currents provided by the sourcing and sinking current sources are steerable and connected to directly provide the feedback current based on the digital output signal. A sigma-delta analog-to-digital converter operating method is also provided.
    Type: Grant
    Filed: May 10, 2013
    Date of Patent: September 23, 2014
    Assignee: Nvidia Corporation
    Inventors: Paul Fontaine, Abdellatif Bellaouar
  • Publication number: 20140266822
    Abstract: A digital-to-time converter (DTC) comprises a gate controller configured to generate a gate enable signal based on first and second digital values so that the gate enable signal has a first enable period and a second enable period for each pair of a first digital value and a second digital value. A gate conditionally passes a main clock signal to a gate output in response to the gate enable signal, the gate thus providing a gated signal at a gate output. A frequency divider generates a frequency divided signal as the output signal of the digital-to-time converter based on the gated signal. The DTC may be calibrated by a time-to-digital converter connected between an input for the main clock signal and an output of a delay element of the DTC.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Inventors: Stephan Henzler, Markus Schimper
  • Publication number: 20140266833
    Abstract: A slope compensation module provides slope compensation of a switched-mode power supply using current mode control. This slope compensation function may be provided by a digital slope compensation generator and a pulse density modulated digital-to-analog converter (PDM DAC) having a selectable response mode low pass filter.
    Type: Application
    Filed: March 10, 2014
    Publication date: September 18, 2014
    Inventors: Bryan Kris, Andreas Reiter, Tibor Futo, Alex Dumais
  • Publication number: 20140266831
    Abstract: The present disclosure relates to a method and architecture to minimize a transient glitch within a current digital-to-analog converter (DAC) comprising an array of identical current unit cells. The current DAC is configured with individual column decoders for even and odd rows of current unit cells, thus allowing for independent control of adjacent rows. The even row and odd row column decoders further comprise thermal decoders with coupled timing encoding which establishes synergy between an adjacent pair of rows. As current units cells within an active row are activated across the row by a counting up of a first column decoder, the current units cells within a next row adjacent the active row are returned to an initial state of the active row by counting down in a second column decoder. Other devices and methods are also disclosed.
    Type: Application
    Filed: April 8, 2013
    Publication date: September 18, 2014
    Applicant: Taiwan Semiconductor Manufacturing Co. Ltd.
    Inventors: Kuo-Yu Chou, Wei Lun Tao, Shang-Fu Yeh, Yi-Che Chen, Calvin Yi-Ping Chao
  • Publication number: 20140266830
    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: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Applicant: QUALCOMM INCORPORATED
    Inventors: Tongyu Song, Sang Min Lee, Derui Kong, Dongwon Seo
  • Publication number: 20140266116
    Abstract: A current mode converter includes a converter stage comprising a first switch, a second switch, an inductor, and a capacitor, and a digital-to-analog converter configured to convert a digital target current signal to an analog current signal. The current mode converter further includes a slope compensation circuit coupled to the digital-to-analog converter and is configured to convert the analog target current signal to a slope compensated analog target signal. A comparator is coupled to the converter stage and the slope compensation stage and is configured to generate and output a signal when a value of an actual analog signal is equal to a value of the slope compensated analog target signal.
    Type: Application
    Filed: March 14, 2013
    Publication date: September 18, 2014
    Inventors: Stephan Henzler, Giacomo Curatolo, Marcin Daniel