Recirculating Patents (Class 341/163)
  • Patent number: 8436761
    Abstract: An analog-to-digital converter including a comparator, a control module, a voltage adjusting module, and an evaluating module is provided. The comparator compares an analog input voltage with a feedback voltage and generates a comparison result. Based on the comparison result, the control module generates a control signal. The voltage adjusting module increases or decreases the feedback voltage toward the analog input voltage according to the control signal. The voltage increase amount and decrease amount provided by the voltage adjusting module are corresponding to a first digital value and a second digital value, respectively. The evaluating module generates the first digital value and the second digital value based on the control signal. According to the first digital value and the second digital value, a digital signal corresponding to the analog input voltage is generated.
    Type: Grant
    Filed: October 26, 2011
    Date of Patent: May 7, 2013
    Inventor: Ping-Ying Wang
  • Patent number: 8427352
    Abstract: An A/D converter circuit includes first to fourth pulse circulation circuits and first and second counters and configured to provide high conversion accuracy irrespective of a temperature change. The first pulse circulation circuit operates with a difference voltage of a specified voltage and an analog input voltage. The first counter outputs a difference of the number of pulse circulation in the first and the second pulse circulation circuits. The third pulse circulation circuit operates with a difference voltage of the specified voltage and a set voltage. The fourth pulse circulation circuit operates with the set voltage. The second counter outputs a difference of the number of pulse circulation in the third and the fourth pulse circulation circuits. When an output value of the second counter reaches a specified value, an output value of the first counter at that time is outputted as A/D conversion data.
    Type: Grant
    Filed: September 15, 2011
    Date of Patent: April 23, 2013
    Assignee: Denso Corporation
    Inventor: Yukihiko Tanizawa
  • Patent number: 8405538
    Abstract: A control circuit connects a capacitor to an input terminal and an output terminal of an operational amplifier and applies a signal charge to charge the capacitor with a switch being turned off. Thus, a conversion voltage corresponding to the signal charge is outputted from the operational amplifier. The control circuit then sets charges, which correspond to the conversion voltage, in capacitors and reallocates the charges among the capacitors by connecting non-common electrodes of the capacitors to either one of a plurality of reference voltage lines in accordance with a conversion result of an A/D conversion circuit with the capacitor being connected to the input terminal and the output terminal of the operational amplifier. The control circuit thereafter performs, a number of times, charge setting, initialization and subsequent charge reallocation in accordance with a residual voltage outputted from the operational amplifier.
    Type: Grant
    Filed: March 17, 2011
    Date of Patent: March 26, 2013
    Assignee: DENSO CORPORATION
    Inventors: Tetsuya Makihara, Masakiyo Horie, Kazutaka Honda
  • Publication number: 20130069811
    Abstract: A redundant signed digit (RSD) analog to digital converter (ADC) receives a high voltage (VRH) and a low voltage (VRL) for use in converting an input signal to a digital signal. A doubling circuit receives the input signal and doubles the input signal to provide a doubled input signal using an amplifier and a first capacitor. The first capacitor has a capacitance of a first magnitude. A VR circuit continues processing the doubled input signal to provide a 2VR signal. A Vref circuit (VR+C5 and C6) provides a first RSD residue signal that is equal to a sum of a reference Vref and the 2VR signal. The first RSD residue signal is produced using the amplifier, a second capacitor, and the high power supply voltage. The second capacitor has a capacitance equal to half that of the first capacitor.
    Type: Application
    Filed: September 20, 2011
    Publication date: March 21, 2013
    Inventor: ROBERT S. JONES, III
  • Patent number: 8395538
    Abstract: A singled-ended, successive approximation register analog-to-digital converter convert an analog input voltage to a digital representation comprising m upper order bits and a number of lower order bits. The SAR ADC comprises SAR logic, a resistive network, multiple switches, and first and second LSB capacitors. The switches also comprises two sets of switches coupled to the resistive network, each set of switches is configured to couple a selected tap to each of the first and second LSB capacitors. When determining the lower order bits, the SAR logic is configured to control the sets of switches to change the first and second taps from one cycle in which one of the lower order bits is determined to a next cycle in which the next of the lower order bits is determined so that the voltage of both taps changes by a decreasing amount with each succeeding bit being determined.
    Type: Grant
    Filed: June 20, 2011
    Date of Patent: March 12, 2013
    Assignee: Texas Instruments Incorporated
    Inventors: Abhijit Kurmar Das, Krishnasawamy Nagaraj, Joonsung Park
  • Patent number: 8390501
    Abstract: A successive approximation register (SAR) analog-to-digital converter (ADC) is disclosed. A first and second capacitor DACs receive a first and second input signals respectively. A first coarse comparator compares an output of the first capacitor DAC with a window reference voltage, a second coarse comparator compares an output of the second capacitor DAC with the window reference voltage, and a fine comparator compares the output of the first capacitor DAC with the output of the second capacitor DAC. A SAR controller receives outputs of the first and second coarse comparators to determine whether the outputs of the first and second capacitor DACs are within a predictive window determined by the window reference voltage. The SAR controller bypasses at least one phase of analog-to-digital conversion of the SAR ADC when the outputs of the first capacitor DAC and the second capacitor DAC are determined to be within the predictive window.
    Type: Grant
    Filed: April 28, 2011
    Date of Patent: March 5, 2013
    Assignees: NCKU Research and Development Foundation, Himax Technologies Limited, Himax Media Solutions, Inc.
    Inventors: Soon-Jyh Chang, Guan-Ying Huang, Chun-Cheng Liu, Chung-Ming Huang, Jin-Fu Lin, Chih-Haur Huang
  • Patent number: 8378864
    Abstract: Successive approximation Analog-to-digital converters (ADCs) and related methods are disclosed. A successive approximation ADC includes a comparator with a comparator output and inputs coupled to a common model signal and a compare input. Control logic generates one or more control signals responsive to the comparator output. A capacitor array includes first sides of capacitors operably coupled to an array output. The capacitor arrays selectively couples each of second sides of the capacitors to an analog input signal and one or more input reference signals responsive to the one or more control signals. A voltage limiter is operably coupled between the array output and the compare input of the comparator and limits a voltage on the compare input to within a predefined range relative to the array output. The successive approximation ADC may also be configured differentially with a second comparator and a second voltage limiter.
    Type: Grant
    Filed: March 16, 2011
    Date of Patent: February 19, 2013
    Assignee: Integrated Device Technology, Inc.
    Inventors: Lijie Zhao, Song Gao, Quinghua Hubert Yue, Jeffrey G. Barrow
  • Patent number: 8362940
    Abstract: A successive approximation register analog-to-digital converter includes: a digital-to-analog converter to generate an analog voltage based on an input voltage sampled in accordance with a sampling clock and a digital code; a comparator to receive the analog voltage; a controller to generate the digital code based on an output of the comparator; a delay circuit to delay a signal based on the output of the comparator and to feed back the delayed signal to a reset terminal of the comparator; an adjustment circuit to count a number of edges of a signal generated in a loop that feeds back the delayed signal, and to adjust an amount of delay of the delay circuit based on a count value; and a sampling clock generation circuit to generate the sampling clock based on the signal generated in the loop and the external clock signal.
    Type: Grant
    Filed: August 4, 2011
    Date of Patent: January 29, 2013
    Assignee: Fujitsu Limited
    Inventor: Masato Yoshioka
  • Patent number: 8344931
    Abstract: The present invention provides an n-bits successive approximation register (SAR) analog-to-digital converting (ADC) circuit, comprising: an n-bits SAR control logic, a p-type capacitor network including a DACp array and a sampling capacitor CSp, an n-type capacitor network including a DACn array and a sampling capacitor CSn; and a comparator for comparing outputs from the p-type capacitor network and the n-type capacitor network, wherein a power supply and ground are directly connected to the p-type capacitor network and the n-type capacitor network without using reference voltages produced by a reference voltage generator. The n-bits SAR control logic comprises n shift registers, n bit registers, and a switching logic. The comparator comprises a first pre-amplifier, a second pre-amplifier and a dynamic latch. Alternative, the comparator comprises a four-input pre-amplifier and a dynamic latch.
    Type: Grant
    Filed: June 1, 2011
    Date of Patent: January 1, 2013
    Assignee: University of Macau
    Inventors: Yan Zhu, Chi-Hang Chan, U-Fat Chio, Sai-Weng Sin, Seng-Pan U, Rui Paulo Da Silva Martins, Franco Maloberti
  • Patent number: 8344927
    Abstract: Provided are an analog digital converting device and a reference voltage controlling method thereof. The analog digital converting device includes: a first reference voltage generating circuit generating a first reference voltage; a second reference voltage generating circuit generating a second reference voltage; a first sub analog digital converter receiving an analog input signal and converting the analog input signal into a first digital signal by using the first reference voltage; an amplifier converting the first digital signal into a voltage corresponding to the first digital signal by using the first reference voltage and amplifying a difference between a voltage level of the analog input signal and a voltage level corresponding to the first digital signal to output a residual signal; and a second sub analog digital converter receiving the residual signal and converting the residual signal into a second digital signal by using the second reference voltage.
    Type: Grant
    Filed: December 30, 2010
    Date of Patent: January 1, 2013
    Assignee: Electronics and Telecommunications Research Institute
    Inventor: Young-deuk Jeon
  • Patent number: 8289198
    Abstract: A switched capacitor circuit, which may be an SAR ADC, includes a plurality of bit switching circuits (33) each including a high-voltage sampling switch circuit (18) having a first terminal (28) coupled to a first terminal of a corresponding capacitor (22) and a second terminal coupled to receive an analog input signal (VSIG). A third terminal of the sampling switch circuit is coupled to an intermediate conductor (19). Each switching circuit (33) also includes a low-voltage conversion switch circuit (30) coupled to the intermediate conductor (19) and a combinational logic circuit (12) applying low-voltage signals to the conversion switch circuit and a level-shifting circuit (16) that generates corresponding high-voltage signals (HV_SIG_DRV) which control coupling of the first terminal (28) to the analog input signal and the intermediate conductor.
    Type: Grant
    Filed: November 2, 2010
    Date of Patent: October 16, 2012
    Assignee: Texas Instruments Incorporated
    Inventors: Vinay Agarwal, Robert E. Seymour
  • Patent number: 8274421
    Abstract: A system for digitizing the magnitude of a first parameter, which can be inferred by applying to a second parameter and digitizing the magnitude of a resulting third parameter. The circuit which applies the second parameter has an associated bias point with which the magnitude of the second parameter varies. The value of the first parameter can result in an error in the value of the second parameter which results in an error being incurred when the digitized value of the third magnitude is used to infer a digitized value of the magnitude of the first parameter. This is avoided by adjusting the bias point with each successive trial and employing a sequential-trial ADC which performs sequential comparisons between the third magnitude and respective decision thresholds, such that there is no error in the magnitude of the second parameter when the third magnitude is equal to the decision threshold for a particular trial.
    Type: Grant
    Filed: July 16, 2010
    Date of Patent: September 25, 2012
    Assignee: Analog Devices, Inc.
    Inventor: Daniel Rey-Losada
  • Patent number: 8274418
    Abstract: An analogue to digital converter uses charge sampling in combination with a successive approximation conversion technique in order to combine anti-alias filtering and quadrature downconversion functions into the data converter. The conversion method is an energy-efficient realization for wide-band radio systems with moderate resolution specifications such as 4G or ultra-wideband radio (UWB). The converter uses two capacitor matrices, one to perform charge sampling, and one to be used simultaneously in the successive approximation technique, so that full use of an input signal is made and efficiency is maximized.
    Type: Grant
    Filed: May 18, 2007
    Date of Patent: September 25, 2012
    Assignee: Nokia Corporation
    Inventor: Kimmo Koli
  • Patent number: 8264389
    Abstract: An analog-to-digital converter has a self-test capability that provides not only an indication of failure or performance degradation but also identifies the failed or degraded component or components. The converter includes a first generator configured to generate a first analog value, a digital-to-analog converter configured to generate a second analog value, a second generator configured to generate a digital value from the comparison of the first analog value with respect to the second analog value, a controller configured to receive a signal indicating a test mode and to generate a configuration signal to the first generator, to receive the digital value and generate a control signal to control the generation of the second analog value, and to generate from the digital value an alarm signal indicating a failure within the analog-to-digital converter or indicating a degradation of the performance of the analog-to-digital converter.
    Type: Grant
    Filed: August 18, 2010
    Date of Patent: September 11, 2012
    Assignee: STMicroelectronics S.r.L.
    Inventors: Gianluca Farabegoli, Mauro Giacomini, Marco Losi
  • Patent number: 8264393
    Abstract: A converter (200) adapted to convert an analog input signal into a digital output signal includes an analog input terminal (205) for receiving the analog input signal, a Redundant Signed Digit (RSD) stage (210) coupled to the analog input terminal, and a digital section (220). The RSD stage is configured to receive the analog input signal at the analog input terminal, produce a first number of bits at a digital output from the analog input signal during a first half of a first clock cycle, provide a residual feedback signal of the analog input signal at the analog input terminal during a second half of the first clock cycle, and produce a second number of bits at the digital output from the residual feedback signal during a first half of a second clock cycle, the second number of bits less than the first number of bits.
    Type: Grant
    Filed: July 9, 2010
    Date of Patent: September 11, 2012
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Douglas A. Garrity, Brandt Braswell, Mohammad Nizam U. Kabir
  • Patent number: 8258991
    Abstract: Successive approximation register (SAR) analog-to-digital converters (ADCs) generally use one or more comparators to convert an analog signal to a digital signal. These comparators, however, can consume a great deal of power, so it is desirable to have a comparator configuration that consumes less power. Here, a multi-bandwidth comparator is provided, which can be switched between different coarse resolution and fine resolution. By using this single multi-bandwidth comparator, lower power consumption with a small amount of area can be achieved.
    Type: Grant
    Filed: August 17, 2010
    Date of Patent: September 4, 2012
    Assignee: Texas Instruments Incorporated
    Inventor: Seetharaman Janakiraman
  • Patent number: 8258992
    Abstract: A sequential comparison-type analog-to-digital converter (ADC) that has improved precision and which is capable of high-speed operation is disclosed, the analog-to-digital converter comprising a digital-to-analog converter that outputs a plurality of different reference analog signals according to a multibit digital signal, a plurality of comparators that compare an input analog signal with the plurality of reference analog signals, and a sequential comparison control circuit that changes bit values of the multibit digital signal in order from higher bits so that at least one of the plurality of reference analog signals becomes closer to the input analog signal and decides the bit values in order from higher bits based on the comparison results and at the same time, correcting the decided higher bit values, wherein the sequential comparison control circuit decides the bit values of the multibit digital signal down to a predetermined bit based on the comparison results of the plurality of comparators and at th
    Type: Grant
    Filed: October 19, 2010
    Date of Patent: September 4, 2012
    Assignee: Semiconductor Technology Academic Research Center
    Inventors: Masao Hotta, Tatsuji Matsuura
  • Patent number: 8237598
    Abstract: Provided is a method for performing analog to digital conversion of a plurality of analog signal channels. The method may comprise successively processing each analog signal channel of a plurality of analog signal channels. The processing of an analog signal channel of the plurality of analog signal channels may comprise: selecting the analog signal channel from the plurality of analog signal channels, generating an analog output signal corresponding to an analog input signal transmitted over the selected analog signal channel, and sampling the analog output signal using a successive approximation register (SAR) converter. Sampling the analog output signal using a SAR converter may comprise sampling the analog output signal a specific number of times to produce a respective plurality of digital samples corresponding to the selected analog input signal.
    Type: Grant
    Filed: July 30, 2010
    Date of Patent: August 7, 2012
    Assignee: National Instruments Corporation
    Inventors: Garritt W. Foote, Hector Rubio
  • Patent number: 8188902
    Abstract: Traditionally, successive approximation register (SAR) analog-to-digital converters (ADCs) using binary search algorithms have consumed power by performing unnecessary switching of a capacitive digital-to-analog converter (CDAC) when a CDAC voltage is relatively close to a sampling analog input signal. Here, a SAR ADC is provided that reduces the number of switching events. To accomplish this, a multi-stage comparator is provided that generates multiple output signals for SAR logic. Based on these outputs, the SAR logic can more efficiently switch its CDAC using a ternary search algorithm to reduce power consumption and improve efficiency.
    Type: Grant
    Filed: August 17, 2010
    Date of Patent: May 29, 2012
    Assignee: Texas Instruments Incorporated
    Inventors: Yujendara Mitikiri, Visvesvaraya Pentakota
  • Patent number: 8164504
    Abstract: A successive approximation resistor analog digital converter (SAR ADC) includes a first conversion unit including a correction capacitor array and a bit capacitor array 2V-1 less than the number of a bit, a second conversion unit configured to differentially operate with the first conversion unit, a comparator configured to output a voltage of a high level or a low level of each capacitor according to output voltages of the first and second conversion units, a successive approximation register (SAR) logic unit configured to receive an output voltage of the comparator to convert the received output voltage into a digital signal, and a correction logic unit configured to receive the digital signal converted by the SAR logic unit and to correct a digital signal of the bit capacitor array using a correction digital signal of the correction capacitor array of the received digital signal.
    Type: Grant
    Filed: September 15, 2010
    Date of Patent: April 24, 2012
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Young Kyun Cho, Young Deuk Jeon, Jae Won Nam, Jong Kee Kwon
  • Patent number: 8134487
    Abstract: An asynchronous analog to digital convertor for converting an analog input signal into a digital output is presented. According to an embodiment, the analog to digital convertor comprises a clock input operable to receive an external clock signal having a clock period, a comparator operable to compare the analog input signal to a reference signal, a digital to analog converter operable to generate the reference signal corresponding to a state of a successive approximation register, and a control block connected to the comparator and to the digital to analog converter. The control block is operable to generate and receive a sequence of control signals according to a successive approximation algorithm, to perform a plurality of comparisons, and to update the state of the successive approximation register thereby generating the digital output.
    Type: Grant
    Filed: September 9, 2010
    Date of Patent: March 13, 2012
    Assignee: Stichting IMEC Nederland
    Inventor: Pieter Harpe
  • Patent number: 8120520
    Abstract: A successive approximation analog/digital converter includes a sample & hold part sampling and holding an intensity of an analog input signal using a single clock cycle of a clock signal; a first comparator comparing the intensity of the analog input signal with comparison voltages determined according to estimated digital values per clock cycle following an operating clock cycle of the sample & hold part; a second comparator comparing the intensity of the analog input signal with a value equal to ½ of a preset reference voltage in the latter half of the operating clock cycle of the sample & hold part; a successive approximation register determining a value of an MSB of a digital value to be converted according to the comparison result of the second comparator and values of bits successive to the MSB according to the comparison result of the first comparator, and generating the estimated digital values by applying estimated values to undetermined bits; and a digital/analog converter generating the
    Type: Grant
    Filed: March 8, 2010
    Date of Patent: February 21, 2012
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Chan Yong Jeong, Chul Woo Kim, Ho Kyu Lee, Chul Gyun Park
  • Patent number: 8115664
    Abstract: An exemplary embodiment of the present invention is an A/D conversion device including: a sample-and-hold circuit that holds an analog input voltage; a sequential conversion register that stores a digital value corresponding to a threshold; a D/A converter that generates an analog voltage corresponding to the digital value stored in the sequential conversion register; a comparator that compares an analog voltage output from the sample-and-hold circuit with an analog voltage obtained from the D/A converter, and outputs a comparison result; a comparison result counter that outputs a determination result according to a count number counted based on the comparison result; and a control circuit that performs control for switching from the comparator function to the A/D conversion function, based on the determination result. During operation of the A/D conversion function, the sequential conversion register sequentially converts the analog voltage held in the sample-and-hold circuit into a digital value.
    Type: Grant
    Filed: April 7, 2010
    Date of Patent: February 14, 2012
    Assignee: Renesas Electronics Corporation
    Inventor: Sumiyuki Kamikisaki
  • Patent number: 8102292
    Abstract: An analog-to-digital converter (ADC) having a successive-approximation register digital-to-analog converter (SARDAC) is described.
    Type: Grant
    Filed: April 2, 2010
    Date of Patent: January 24, 2012
    Assignee: Cypress Semiconductor Corporation
    Inventor: David Van Ess
  • Publication number: 20120007762
    Abstract: A converter (200) adapted to convert an analog input signal into a digital output signal includes an analog input terminal (205) for receiving the analog input signal, a Redundant Signed Digit (RSD) stage (210) coupled to the analog input terminal, and a digital section (220). The RSD stage is configured to receive the analog input signal at the analog input terminal, produce a first number of bits at a digital output from the analog input signal during a first half of a first clock cycle, provide a residual feedback signal of the analog input signal at the analog input terminal during a second half of the first clock cycle, and produce a second number of bits at the digital output from the residual feedback signal during a first half of a second clock cycle, the second number of bits less than the first number of bits.
    Type: Application
    Filed: July 9, 2010
    Publication date: January 12, 2012
    Inventors: DOUGLAS A. GARRITY, Brandt Braswell, Mohammad Nizam U. Kabir
  • Patent number: 8081097
    Abstract: An analog-to-digital converter includes a sample and hold unit, a successive control unit, a look-up memory, and a calibrating comparator, which further includes a positive input end, a negative input end, a timing signal input end, a data port, a latch unit, an enable switch, a first controllable resistor, a second controllable resistor, a reset switch assembly, a controllable capacitive device, and an output end.
    Type: Grant
    Filed: June 16, 2010
    Date of Patent: December 20, 2011
    Assignee: PixArt Imaging Inc.
    Inventor: Cheng-Chung Hsu
  • Patent number: 8040271
    Abstract: An A/D conversion apparatus includes: a first and a second D/A converter to sample an analog signal and successively compare the analog signal and a reference signal to generate a first and a second comparison signal respectively; a first comparator to compare the first comparison signal generated by the first D/A converter with a benchmark signal; a second comparator to compare the second comparison signal generated by the second D/A converter with the benchmark signal; and a converter to convert the analog signal to a digital signal according to results of the comparisons by the first and second comparators.
    Type: Grant
    Filed: September 3, 2009
    Date of Patent: October 18, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masanori Furuta, Tomohiko Ito, Tetsuro Itakura
  • Patent number: 8018370
    Abstract: A system is configured and a method is provided for receiving an input ratio represented by a first input signal and a second input signal, and producing an output ratio represented by a first output signal and a second output signal. The system is constructed and the method is provided for alternately operating in at least two time periods, wherein in one time period the first input signal, a low accuracy amplifier, and the first output signal are selectively coupled, and in another time period the input signal, the low accuracy amplifier, a high accuracy attenuator, and the second output signal are selectively coupled so as to maintain the output ratio proportional to the input ratio.
    Type: Grant
    Filed: February 1, 2010
    Date of Patent: September 13, 2011
    Assignee: Linear Technology Corporation
    Inventors: Andrew J. Thomas, Joseph L. Sousa
  • Patent number: 8009214
    Abstract: A column parallel image sensor such as an active pixel sensor includes a calibration circuit for the readout circuit within the active pixel sensor. The calibration circuit produces a value that is stored and used to offset any noise in the A/D converter. The calibration is carried out each time that each row is read out so in effect the calibration's individual for each pixel. Hence, any noise within the calibration evens out within the image, and is effectively random within the image and hence becomes less noticeable within the image.
    Type: Grant
    Filed: June 13, 2007
    Date of Patent: August 30, 2011
    Assignee: Forza Silicon
    Inventor: Steven Huang
  • Patent number: 8004449
    Abstract: A D/A converter includes plus-side and minus-side input terminals; plus-side and minus-side D/A converters each including plural plus-side or minus-side capacitors having capacitance values weighted by the powers of two, a plus-side or minus-side output terminals connected to first electrodes of the plus-side or minus-side capacitors, and plural plus-side or minus-side switches for connecting each second electrode of the plus-side or minus-side capacitors to either the plus-side or minus-side input terminal, a plus-side reference voltage terminal or a minus-side reference voltage terminal according to plus-side or minus-side control digital signals; and plural short-circuit switches provided between identically weighted plus-side and minus-side capacitors respectively.
    Type: Grant
    Filed: April 9, 2010
    Date of Patent: August 23, 2011
    Assignee: Fujitsu Limited
    Inventor: Masato Yoshioka
  • Patent number: 7986257
    Abstract: A comparator circuit includes a first comparator comparing an input signal to a first comparison value and generating a first determination signal, a second comparator comparing the input signal to a second comparison value different from the first comparison value and generating a second determination signal, and an output selecting circuit selecting a signal generated first from the first determination signal and the second determination signal, and outputting the selected signal as a determination signal.
    Type: Grant
    Filed: August 7, 2009
    Date of Patent: July 26, 2011
    Assignee: Fujitsu Limited
    Inventor: Masato Yoshioka
  • Patent number: 7978118
    Abstract: A 1.5-bit algorithmic analog-to-digital converter (ADC) generates a digital value representative of an input voltage. The ADC implements a series of conversion cycles for a conversion operation. Each conversion cycle has three sub-cycles: a scaling sub-cycle, a first sample sub-cycle, and a second sample sub-cycle. In the scaling sub-cycle, the residual voltage from the previous conversion cycle is doubled to generate a first voltage. In the first sample sub-cycle, a first bit of a corresponding bit pair is determined based on the polarity of the first voltage. The first voltage is either increased or decreased by a reference voltage based on the polarity of the first voltage to generate a second voltage. In the second sample sub-cycle, a second bit of the corresponding bit pair is determined based on the polarity of the second voltage.
    Type: Grant
    Filed: February 1, 2010
    Date of Patent: July 12, 2011
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Ahmed Abdell-Ra'oof Younis, Michael A. Nix
  • Patent number: 7978117
    Abstract: A multi-stage dual successive approximation register analog-to-digital converter (SAR ADC) and a method of performing analog-to-digital conversion using the same are provided. The multi-stage dual SAR ADC includes: a plurality of SAR ADC stages for converting an analog input voltage into a predetermined bit digital signal, each SAR ADC stage being serially connected to one another and including two SAR ADCs; and at least one residue amplifier respectively connected between every two successive SAR ADC stages, amplifying residue voltage output from a previous SAR ADC stage to output the amplified residue voltage to a next SAR ADC stage. The two SAR ADCs of the previous SAR ADC stage share the residue amplifier.
    Type: Grant
    Filed: August 11, 2009
    Date of Patent: July 12, 2011
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Young Deuk Jeon, Young Kyun Cho, Jae Won Nam, Jong Kee Kwon
  • Patent number: 7973684
    Abstract: Auto-calibration of the analog circuits occurs when requested by a user and/or the occurrence of an event(s). The user may invoke an auto-calibration on demand through an auto-calibration (ACAL) input to the mixed-signal integrated circuit. An external voltage calibration (VCAL) input may be used for auto-calibration of the mixed-signal integrated circuit to a user-supplied common-mode voltage reference. Auto-calibration of the mixed-signal integrated circuit may also be initiated upon the occurrence of any one or more of the following events: 1) detection of auto-calibration data corruption, e.g., parity checking of auto-calibration data values digitally stored in the mixed-signal integrated circuit; 2) an internal timer that causes a calibration request after a programmable timeout period, 3) change in the internal integrated circuit die temperature as determined by a temperature sensor, and 4) a change in the power supply and/or internal supply voltage(s).
    Type: Grant
    Filed: September 15, 2009
    Date of Patent: July 5, 2011
    Assignee: Microchip Technology Incorporated
    Inventors: James B. Nolan, Kumen Blake
  • Patent number: 7973693
    Abstract: During successive approximation analog to digital conversion a series of successive digital reference values is selected that converges towards a digital representation of an analog input signal. An analog reference signal is generated dependent on the successive digital reference values and compared to the analog input signal. The digital reference values are selected dependent on comparison results. In the selection of the digital reference values successive steps between digital reference values are each selected dependent on values of the comparator result from a plurality of preceding recursion cycles. The comparison results define a series of successively narrower ranges of digital values that contain a digital representation of the analog input signal. Use of a plurality of comparator results for selecting the steps in the digital reference values makes it possible to reduce uncertainty about whether the comparison result has settled.
    Type: Grant
    Filed: May 27, 2008
    Date of Patent: July 5, 2011
    Assignee: NXP B.V.
    Inventors: Simon M. Louwsma, Maarten Vertregt
  • Patent number: 7956787
    Abstract: A method for operating an N-bit SAR ADC as a greater than N-bit resolution SAR ADC includes the steps of taking a plurality of samples for each analog value being converted to a digital value by the SAR ADC. A portion of an LSB is added to all but one of the plurality of samples. The plurality of samples are then accumulated and output as a digital value. The digital value has a resolution greater than the N-bit resolution of the SAR ADC.
    Type: Grant
    Filed: December 19, 2008
    Date of Patent: June 7, 2011
    Assignee: Silicon Laboratories Inc.
    Inventors: Alan Westwick, Xiaoling Guo
  • Patent number: 7952509
    Abstract: A successive approximation A/D conversion circuit for simultaneously sampling N channels of analog signals and for A/D converting the sampled analog signals, includes: N capacitive main DACs; a resistive sub DAC; N comparators; and a successive approximation control circuit, wherein the successive approximation control circuit determines high-order bit values of A/D conversion results of the N channels of analog signals by controlling the N capacitive main DACs and the N comparators, and determines low-order bit values of the A/D conversion results of the N channels of analog signals by controlling the resistive sub DAC and the N comparators.
    Type: Grant
    Filed: November 17, 2009
    Date of Patent: May 31, 2011
    Assignee: Fujitsu Semiconductor Limited
    Inventors: Kenta Aruga, Suguru Tachibana, Koji Okada
  • Patent number: 7928871
    Abstract: A successive approximation A/D converter includes a capacitive D/A converter including capacitors, and generates a voltage based on the input voltage and a first digital signal including J bits; a resistive D/A converter that generates a voltage based on a second digital signal; a capacitor that capacity-couples the voltage to an output node; a comparator that generates a result based on the voltage; a control circuit that supplies the first digital signal to the capacitive D/A converter according to the result and outputs a third digital signal indicating a correction and a fourth digital signal including K bits; and a digital calculating circuit that generates the second digital signal including K bits based on the third digital signal and the fourth digital signal, and supplies the second digital signal to the resistive D/A converter, a (J+K) bit digital data is generated based on the input signal.
    Type: Grant
    Filed: March 23, 2009
    Date of Patent: April 19, 2011
    Assignee: Fujitsu Semiconductor Limited
    Inventors: Kenta Aruga, Suguru Tachibana, Koji Okada
  • Patent number: 7928882
    Abstract: An integrated circuit comprises a plurality of sensing circuits (12), each for detecting whether a respective physical operating parameter is above or below a respective reference value. The integrated circuit contains a serial shift register (11) for shifting digital data signals that represent the respective reference values from a successive approximation update circuit (14) to the sensing circuits (12) and back to the successive approximation update circuit (14). Detection results of the sensing circuits (12) are shifted to the successive approximation update circuit (14) with the digital data signals. The successive approximation update circuit (14) is used to form the digital data so that the reference values form successive approximations of the physical operating parameter values during an analog to digital conversion process. In this way the successive approximation update circuit (14) is shared by a plurality of sensing circuits (12).
    Type: Grant
    Filed: November 7, 2005
    Date of Patent: April 19, 2011
    Assignee: NXP B.V.
    Inventors: Hendricus J M Veendrick, Marcel Pelgrom, Violeta Petrescu
  • Patent number: 7916063
    Abstract: In one embodiment, an analog to digital converter includes a comparator having a first input, a second input and an output, the first input being coupled to an analog signal, a successive approximation register having a serial input coupled to the output of the comparator, and being configured to generate a plurality of control signals and an N-bit digital value corresponding to the analog signal, and a digital to analog converter having an input coupled to the plurality of control signals, the digital to analog converter further comprising a first, a second, and a third capacitor and a plurality of switches controlled by the plurality of control signals and being configured to couple the first capacitor to the second capacitor and the third capacitor to the second capacitor mutually exclusively to share charge on the first capacitor and charge on the third capacitor with charge on the second capacitor and to generate an analog signal on the second capacitor, the second capacitor being coupled to the second i
    Type: Grant
    Filed: September 28, 2009
    Date of Patent: March 29, 2011
    Assignee: Robert Bosch GmbH
    Inventors: Clemenz Portmann, Christoph Lang
  • Patent number: 7889111
    Abstract: A conversion operation B is performed with respect to a sample value R in an A/D conversion stage 101 to generate a conversion result D3, and a sampling operation A is performed with respect to this conversion result D3 in an A/D conversion stage 103. The conversion operation B is performed with respect to a sample value in an A/D conversion stage 105 to generate a conversion result D4, and the sampling operation A is performed with respect to the conversion result D4 in an A/D conversion stage 107. The conversion operation B is performed with respect to a sample value in an A/D conversion stage 107 to generate a conversion result D5, and the sampling operation A is performed with respect to this conversion result D5 in an A/D conversion stage 101. The conversion operation B is performed with respect to a sample value in the A/D conversion stage 103 to generate a conversion result D6, and the sampling operation A is performed with respect to the conversion result D6 in the A/D conversion stage 105.
    Type: Grant
    Filed: June 8, 2007
    Date of Patent: February 15, 2011
    Assignee: National University Corporation Shizuoka University
    Inventor: Shoji Kawahito
  • Patent number: 7884749
    Abstract: An A/D converting apparatus includes a first A/D converter to sample an analog input signal having a D/A converter to generate a comparative signal for successive comparison with the analog input signal, a signal generator generate a differential signal between the analog input signal and the comparative signal, and a comparator to compare the comparative signal with a standard value to generate a first digital signal exhibiting high-order bit; an amplifier to amplify the differential signal to generate a residue signal; and a second A/D converter to sample the residue signal to generate a second digital signal exhibiting low-order bit.
    Type: Grant
    Filed: January 6, 2009
    Date of Patent: February 8, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masanori Furuta, Tomohiko Ito, Takafumi Yamaji, Tetsuro Itakura
  • Patent number: 7876254
    Abstract: A data converter for converting analog signals to digital signals, or for converting digital signals to analog signals is provided. In one embodiment, a production self-test is provided. In one embodiment, a high-speed lower-resolution method or mode for a data converter is provided. In one embodiment, a differential data converter with a more stable comparator common mode voltage is provided. In one embodiment, the input range of a digitally calibrated data converter is provided and maintained so that there is no loss in input range due to the calibration. In one embodiment, digital post-processing of an uncalibrated result using a previously stored calibration value is provided.
    Type: Grant
    Filed: September 30, 2008
    Date of Patent: January 25, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Michael T. Berens, James R. Feddeler
  • Patent number: 7868795
    Abstract: A data converter for converting analog signals to digital signals, or for converting digital signals to analog signals is provided. In one embodiment, a production self-test is provided. In one embodiment, a high-speed lower-resolution method or mode for a data converter is provided. In one embodiment, a differential data converter with a more stable comparator common mode voltage is provided. In one embodiment, the input range of a digitally calibrated data converter is provided and maintained so that there is no loss in input range due to the calibration. In one embodiment, digital post-processing of an uncalibrated result using a previously stored calibration value is provided.
    Type: Grant
    Filed: September 30, 2008
    Date of Patent: January 11, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Michael T. Berens, James R. Feddeler
  • Patent number: 7868796
    Abstract: A data converter for converting analog signals to digital signals, or for converting digital signals to analog signals is provided. In one embodiment, a production self-test is provided. In one embodiment, a high-speed lower-resolution method or mode for a data converter is provided. In one embodiment, a differential data converter with a more stable comparator common mode voltage is provided. In one embodiment, the input range of a digitally calibrated data converter is provided and maintained so that there is no loss in input range due to the calibration. In one embodiment, digital post-processing of an uncalibrated result using a previously stored calibration value is provided.
    Type: Grant
    Filed: September 30, 2008
    Date of Patent: January 11, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Michael T. Berens, James R. Feddeler
  • Patent number: 7834796
    Abstract: An analog-to-digital converter (ADC) and a battery operated electronic device comprising the ADC. The ADC comprising an input switch; an array of binary-weighted capacitors, the array of capacitors receiving the input voltage signal via the input switch in an on state of the input switch; a plurality of switches, each switch connected in series with a respective one of the capacitors at an opposite side compared to the input switch, wherein a VDD signal is applied to each switch in one switching state and ground in another switching state; a comparator having as one input a voltage from the input switch side of the array of capacitors and as another input a voltage of VDD/2; and a switch control unit coupled to an output of the comparator for controlling the switches based on the output from the comparator.
    Type: Grant
    Filed: February 2, 2007
    Date of Patent: November 16, 2010
    Assignee: National University of Singapore
    Inventors: Yong Ping Xu, Honglei Wu
  • Patent number: 7821441
    Abstract: A successive approximation analog-to-digital converter includes a capacitor array having a plurality of switch capacitors therein with varying weights, each having a common plate connected to a common node and a switched plate. A SAR controller samples an input voltage on said capacitor array in a sampling phase and redistributes the charge stored therein in a conversion phase by selectively increasing the voltage on select capacitors of the capacitor array in accordance with a SAR conversion algorithm. Circuitry controls the sampling of the input voltage by the capacitor array and is responsive to at least one applied bias current. The at least one applied bias current operates at a first level responsive to a first mode of operation of the SAR ADC and operates at a second level responsive to a second mode of operation of the SAR ADC.
    Type: Grant
    Filed: December 19, 2008
    Date of Patent: October 26, 2010
    Assignee: Silicon Laboratories Inc.
    Inventors: Alan Westwick, Xiaoling Guo
  • Patent number: 7796079
    Abstract: The analog-to-digital converter provided herein includes a capacitor bank comprising a plurality of binary-weighted capacitors, an operational amplifier having an inverting input node, a noninverting input node coupled to analog ground, and an output node, a reset switch, and an input switch. The reset switch is located between the capacitor bank and the operational amplifier, and it selectively couples the capacitor bank to the inverting input node. The input switch has its common terminal coupled to the capacitor bank, and the input switch selectively couples the capacitor bank to either an analog input voltage, a floating terminal, or analog ground. The capacitor bank includes N binary-weighted capacitors and one balancing capacitor that has a unit capacitance. During operation, the analog-to-digital converter generates an N-bit digital output and one polarity bit from the analog input voltage.
    Type: Grant
    Filed: January 28, 2009
    Date of Patent: September 14, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Ashish Khanna, Sung Jin Jo
  • Patent number: 7782234
    Abstract: The method and system for converting an analog value into a digital equivalent using a plurality of conversion engines are disclosed. In one embodiment the plurality of conversion engines comprise N DACs associated with M comparators, wherein M is substantially greater than N, wherein M and N are integers, wherein each of the N CAP DACs has an associated P CAP DAC and an N CAP DAC, a method includes generating voltage differences between P CAP DACs and N CAP DACs such that they produce M threshold voltages. The plurality of conversion engines operate in a first phase of the conversion by inputting the produced M threshold voltages to associated inputs of M comparators so that more than one bit can be determined from a sampled signal during each successive approximation trial.
    Type: Grant
    Filed: May 31, 2007
    Date of Patent: August 24, 2010
    Assignee: Analog Devices, Inc.
    Inventor: Fazil Ahmad
  • Patent number: RE43639
    Abstract: A technique for correcting charge transfer inefficiencies in a Charge Coupled Device (CCD). The basic approach is to estimate the charge entering at a given stage in a CCD pipeline, and to then determine an estimate of the error introduced by the accumulated leftover charge that will be present at a second point, farther down the pipeline. The error is then corrected by injecting a correcting charge at a third point, farther still down the CCD pipeline. The invention is used, in one embodiment, to correct the output of a charge to digital converter, although principals of the invention may be used for other types of circuits.
    Type: Grant
    Filed: June 29, 2009
    Date of Patent: September 11, 2012
    Assignee: Kenet, Inc.
    Inventors: Jeffrey D. Kurtze, Michael P. Anthony