Patents by Inventor Meng-Fan Chang

Meng-Fan Chang has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10770142
    Abstract: The present disclosure provides a control circuit of a memory array. The control circuit includes a first switch and a set termination circuit. The first switch is connected between a first voltage source and a data line of a resistive memory cell of the memory array. The set termination circuit has a first terminal connected to a control terminal of the first switch and a second terminal connected to the data line of the resistive memory cell of the memory array. When a data line voltage of the data line decreases to be lower than a first voltage in a first duration of the resistive memory cell performing a set operation, the set termination circuit turns off the first switch to terminate the set operation by stopping providing the first voltage of the first voltage source to the data line.
    Type: Grant
    Filed: December 13, 2018
    Date of Patent: September 8, 2020
    Assignee: NATIONAL TSING HUA UNIVERSITY
    Inventors: Meng-Fan Chang, Wen-Zhang Lin, Li-Ya Lai
  • Patent number: 10748612
    Abstract: A sensing circuit with adaptive local reference generation of a resistive memory is configured to adaptively sense a first bit line current of a first bit line and a second bit line current of a second bit line via one sense amplifier. The sense amplifier has a first output node and a second output node. The adaptive local reference generator is electrically connected to the sense amplifier and generating a reference current equal to a sum of the second bit line current and a local reference current. A first bit line current flows through the first output node during a first bit line time interval. A second bit line current flows through the first output node during a second bit line time interval. The first bit line time interval is different from the second bit line time interval.
    Type: Grant
    Filed: July 8, 2019
    Date of Patent: August 18, 2020
    Assignee: NATIONAL TSING HUA UNIVERSITY
    Inventors: Wei-Yu Lin, Meng-Fan Chang
  • Patent number: 10734039
    Abstract: A voltage-enhanced-feedback sense amplifier of a resistive memory is configured to sense a first bit line and a second bit line. The voltage-enhanced-feedback sense amplifier includes a voltage sense amplifier and a voltage-enhanced-feedback pre-amplifier. The voltage-enhanced-feedback pre-amplifier is electrically connected to the voltage sense amplifier. A first bit-line amplifying module receives a voltage level of the second input node to suppress a voltage drop of the first bit line and amplifies a voltage level of the first input node according to a voltage level of the first bit line. A second bit-line amplifying module receives the voltage level of the first input node to suppress a voltage drop of the second bit line and amplifies the voltage level of the second input node according to a voltage level of the second bit line. A margin enhanced voltage difference is greater than a read voltage difference.
    Type: Grant
    Filed: September 27, 2018
    Date of Patent: August 4, 2020
    Assignee: NATIONAL TSING HUA UNIVERSITY
    Inventors: Meng-Fan Chang, Huan-Ting Lin
  • Patent number: 10636481
    Abstract: A memory cell for computing-in-memory applications is controlled by a first bit line, a second bit line, a word line and a read word line. The read word line transmits an input value. The memory cell includes a plurality of read-decoupled cells. Each of the read-decoupled cells stores a weight and includes a first read-decoupled transistor and a second read-decoupled transistor. The first read-decoupled transistor has a first transistor width and is controlled by the weight. The second read-decoupled transistor has a second transistor width equal to the first transistor width and generates a read bit line signal according to the input value, the weight and the second transistor width. The second transistor width of the second read-decoupled transistor of one of the read-decoupled cells is two times larger than the second transistor width of the second read-decoupled transistor of another one of the read-decoupled cells.
    Type: Grant
    Filed: May 13, 2019
    Date of Patent: April 28, 2020
    Assignee: NATIONAL TSING HUA UNIVERSITY
    Inventors: Meng-Fan Chang, Xin Si, Yung-Ning Tu, Jia-Jing Chen
  • Publication number: 20200105315
    Abstract: A voltage-enhanced-feedback sense amplifier of a resistive memory is configured to sense a first bit line and a second bit line. The voltage-enhanced-feedback sense amplifier includes a voltage sense amplifier and a voltage-enhanced-feedback pre-amplifier. The voltage-enhanced-feedback pre-amplifier is electrically connected to the voltage sense amplifier. A first bit-line amplifying module receives a voltage level of the second input node to suppress a voltage drop of the first bit line and amplifies a voltage level of the first input node according to a voltage level of the first bit line. A second bit-line amplifying module receives the voltage level of the first input node to suppress a voltage drop of the second bit line and amplifies the voltage level of the second input node according to a voltage level of the second bit line. A margin enhanced voltage difference is greater than a read voltage difference.
    Type: Application
    Filed: September 27, 2018
    Publication date: April 2, 2020
    Inventors: Meng-Fan CHANG, Huan-Ting LIN
  • Patent number: 10607698
    Abstract: The present disclosure provides a control circuit of a memory array. The control circuit includes a first switch and a set termination circuit. The first switch is connected between a first voltage source and a data line of a resistive memory cell of the memory array. The set termination circuit has a first terminal connected to a control terminal of the first switch and a second terminal connected to the data line of the resistive memory cell of the memory array. When a data line voltage of the data line decreases to be lower than a first voltage in a first duration of the resistive memory cell performing a set operation, the set termination circuit turns off the first switch to terminate the set operation by stopping providing the first voltage of the first voltage source to the data line.
    Type: Grant
    Filed: December 13, 2018
    Date of Patent: March 31, 2020
    Assignee: NATIONAL TSING HUA UNIVERSITY
    Inventors: Meng-Fan Chang, Wen-Zhang Lin, Li-Ya Lai
  • Patent number: 10510406
    Abstract: An operating method of the soft-verify write assist circuit of the resistive memory provides a voltage level applying step, a write operating step and a write voltage controlling step. The voltage level applying step is for applying a plurality of voltage levels to the reference voltage, the word line and the switching signal, respectively. The write operating step is for driving the memory cell to perform in a set process or a reset process via the first three-terminal switching element, the second three-terminal switching element and the soft-verify controlling unit during a write operation. The write voltage controlling step is for controlling the write voltage to be increased in the ramping cycle and decreased in the soft-verify cycle.
    Type: Grant
    Filed: October 23, 2018
    Date of Patent: December 17, 2019
    Assignee: NATIONAL TSING HUA UNIVERSITY
    Inventors: Meng-Fan Chang, Huan-Ting Lin, Tsung-Yuan Huang, Wei-Hao Chen, Han-Wen Hu
  • Patent number: 10510386
    Abstract: A dynamic bit-line clamping circuit for computing-in-memory applications is configured to clamp a bit line via at least one reference signal and includes a clamping node, a first clamping unit, a second clamping unit, a first feedback controlling unit and a second feedback controlling unit. The first clamping unit is electrically connected between the bit line and the clamping node. The second clamping unit is electrically connected between the clamping node and a power source voltage and includes a switch. The second feedback controlling unit is electrically connected to the clamping node and the switch. The second feedback controlling unit generates a switching signal according to the at least one reference signal and a voltage level of the clamping node. The switch is switched by the switching signal so as to clamp the voltage level of the clamping node according to the at least one reference signal.
    Type: Grant
    Filed: August 29, 2018
    Date of Patent: December 17, 2019
    Assignee: NATIONAL TSING HUA UNIVERSITY
    Inventors: Meng-Fan Chang, Wei-Hao Chen, Wei-Yu Lin
  • Patent number: 10481965
    Abstract: Counting status circuits are electrically coupled to corresponding status elements. The status elements selectably store a bit status of a bit line coupled to a memory array. The bit status can indicate one of at least pass and fail. The counting status circuits are electrically coupled to each other in a sequential order. Control logic causes processing of the counting status circuits in the sequential order to determine a total of the memory elements that store the bit status. The total number of memory elements that store the bit status indicate the number of error bits or non-error bits, which can help determine whether there are too many errors to be fixed by error correction codes.
    Type: Grant
    Filed: December 22, 2016
    Date of Patent: November 19, 2019
    Assignee: MACRONIX INTERNATIONAL CO., LTD.
    Inventors: Yih-Shan Yang, Shou-Nan Hung, Chun-Hsiung Hung, Yao-Jen Kuo, Meng-Fan Chang
  • Patent number: 10410690
    Abstract: A reference-free multi-level sensing circuit for computing-in-memory applications is controlled by a first bit line and a second bit line. An encoding unit generates a first register output value and a plurality of encoded values. The first register output value feedback controls a precharging unit so as to enable the precharging unit to precharge one of the first bit line and the second bit line according to the first register output value. A voltage level of the one of the first bit line and the second bit line is lower than a voltage level of the other one of the first bit line and the second bit line. The encoded values and the first register output value are formed a multi-bit signal to estimate voltage levels of the first bit line and the second bit line.
    Type: Grant
    Filed: August 22, 2018
    Date of Patent: September 10, 2019
    Assignee: NATIONAL TSING HUA UNIVERSITY
    Inventors: Meng-Fan Chang, Jia-Jing Chen
  • Patent number: 10381071
    Abstract: A multi-bit computing circuit for computing-in-memory applications is controlled by an input port and includes a memory cell array and a capacitor sharing unit. The memory cell array includes a plurality of memory cells connected to the input port. The memory cells store a weight which is formed in two's complement. The capacitor sharing unit includes a plurality of switches, a plurality of capacitors and a sense amplifier. The switches are electrically connected to the memory cells, respectively. The capacitors are electrically connected to the switches, respectively. The sense amplifier is electrically connected to the capacitors and generates a total operational value. The capacitors are located among the switches and the sense amplifier, and the switches are switched to enable the total operational value to be equal to the input value multiplied by the weight. The present disclosure utilizes 8T SRAM cells without an extra DAC structure.
    Type: Grant
    Filed: July 30, 2018
    Date of Patent: August 13, 2019
    Assignee: NATIONAL TSING HUA UNIVERSITY
    Inventors: Xin Si, Meng-Fan Chang
  • Patent number: 10340003
    Abstract: An input-pattern aware reference generation system for a memory cell array having a plurality of word lines crossing a plurality of bit lines includes an input counting circuit, a reference array, and a reference word line control circuit. The input counting circuit receives the input signal of the memory cell array, discovers input activated word lines according to the input signal and generates a number signal representing a number of the input activated word lines. The reference array includes a plurality of reference memory cells storing a predetermined set of weights. The reference word line control circuit is electrically connected between the input counting circuit and the reference array. Moreover, the reference word line control circuit controls the reference array to generate a plurality of reference signals being able to distinguish candidates of the computational result of the bit lines in the memory cell array.
    Type: Grant
    Filed: July 6, 2018
    Date of Patent: July 2, 2019
    Assignee: National Tsing Hua University
    Inventors: Meng-Fan Chang, Wei-Hao Chen
  • Publication number: 20190115075
    Abstract: The present disclosure provides a control circuit of a memory array. The control circuit includes a first switch and a set termination circuit. The first switch is connected between a first voltage source and a data line of a resistive memory cell of the memory array. The set termination circuit has a first terminal connected to a control terminal of the first switch and a second terminal connected to the data line of the resistive memory cell of the memory array. When a data line voltage of the data line decreases to be lower than a first voltage in a first duration of the resistive memory cell performing a set operation, the set termination circuit turns off the first switch to terminate the set operation by stopping providing the first voltage of the first voltage source to the data line.
    Type: Application
    Filed: December 13, 2018
    Publication date: April 18, 2019
    Inventors: Meng-Fan CHANG, Wen-Zhang LIN, Li-Ya LAI
  • Publication number: 20190115074
    Abstract: The present disclosure provides a control circuit of a memory array. The control circuit includes a first switch and a set termination circuit. The first switch is connected between a first voltage source and a data line of a resistive memory cell of the memory array. The set termination circuit has a first terminal connected to a control terminal of the first switch and a second terminal connected to the data line of the resistive memory cell of the memory array. When a data line voltage of the data line decreases to be lower than a first voltage in a first duration of the resistive memory cell performing a set operation, the set termination circuit turns off the first switch to terminate the set operation by stopping providing the first voltage of the first voltage source to the data line.
    Type: Application
    Filed: December 13, 2018
    Publication date: April 18, 2019
    Inventors: Meng-Fan CHANG, Wen-Zhang LIN, Li-Ya LAI
  • Patent number: 10262725
    Abstract: A selective bit-line sensing method is provided. The selective bit-line sensing method includes the steps of: generating a neuron weights information, the neuron weights information defines a distribution of 0's and 1's storing in the plurality of memory cells of the memory array; and selectively determining either the plurality of bit-lines or the plurality of complementary bit-lines to be sensed in a sensing operation according to the neuron weights information. When the plurality of bit-lines are determined to be sensed, the plurality of first word-lines are activated by the artificial neural network system through the selective bit-line detection circuit, and when the plurality of complementary bit-lines are determined to be sensed, the plurality of second word-lines are activated by the artificial neural network system.
    Type: Grant
    Filed: November 30, 2017
    Date of Patent: April 16, 2019
    Assignee: NATIONAL TSING HUA UNIVERSITY
    Inventors: Meng-Fan Chang, Win-San Khwa, Jia-Jing Chen
  • Patent number: 10262726
    Abstract: A transpose accessing memory device is provided, the global word-lines configured to be selected as horizontal word-lines in a row access mode in that at least one row of the memory array is selected to be access, and the corresponding local I/O circuit is configured to guide signals of the local bit-lines coupled to the selected SRAM memory cells to the corresponding horizontal global bit-lines in response to select signals from the global word-lines, and the global word-lines configured to be selected as vertical word-lines in a column access mode in that at least one column of the memory array is selected to be access, and the corresponding local I/O circuit is configured to guide signals of the local bit-lines coupled to the selected SRAM memory cells to the corresponding vertical global bit-lines in response to select signals from the global word-lines.
    Type: Grant
    Filed: December 11, 2017
    Date of Patent: April 16, 2019
    Assignee: NATIONAL TSING HUA UNIVERSITY
    Inventor: Meng-Fan Chang
  • Patent number: 10249360
    Abstract: A method and a circuit for generating a reference voltage are provided. The circuit includes: a first column of dummy neurons with weight 0 and a second column of dummy neurons with weight 1, wherein the plurality word-lines are connected to the dummy neurons in the first and second columns, respectively; a bit-line connected to a voltage source and the first column of dummy neurons; a complementary bit-line is connected to the voltage source and the second column of dummy neurons, wherein when the artificial neural network system is operated to sense the neurons of the memory cell array, one or more of the plurality of word-lines are activated, and the corresponding dummy neurons of the first column and the second column are activated to generate the reference voltage at the output end for sensing the neurons of the memory cell array.
    Type: Grant
    Filed: November 30, 2017
    Date of Patent: April 2, 2019
    Assignee: NATIONAL TSING HUA UNIVERSITY
    Inventors: Meng-Fan Chang, Win-San Khwa, Jia-Jing Chen
  • Patent number: 10204681
    Abstract: The present disclosure provides a control circuit of a memory array. The control circuit includes a first switch and a set termination circuit. The first switch is connected between a first voltage source and a data line of a resistive memory cell of the memory array. The set termination circuit has a first terminal connected to a control terminal of the first switch and a second terminal connected to the data line of the resistive memory cell of the memory array. When a data line voltage of the data line decreases to be lower than a first voltage in a first duration of the resistive memory cell performing a set operation, the set termination circuit turns off the first switch to terminate the set operation by stopping providing the first voltage of the first voltage source to the data line.
    Type: Grant
    Filed: May 9, 2017
    Date of Patent: February 12, 2019
    Assignee: NATIONAL TSING HUA UNIVERSITY
    Inventors: Meng-Fan Chang, Wen-Zhang Lin, Li-Ya Lai
  • Patent number: 10192611
    Abstract: The present provides a sensing circuit, a set of pre-amplifiers, and an operating method thereof. The set of pre-amplifiers includes a first pre-amplifier and a second pre-amplifier. The first pre-amplifier is coupled to a first input terminal of the sense amplifier. The second pre-amplifier is coupled to a second input terminal of the sense amplifier. The first pre-amplifier and the second pre-amplifier respectively performs a discharging operation to discharge the first input terminal and the second input terminal of the sense amplifier after the first input terminal and the second input terminal of the sense amplifier are charged to a predetermined voltage. One of the first pre-amplifier and the second pre-amplifier amplifies a voltage difference between the first input terminal and the second input terminal of the sense amplifier by terminating the discharging operation of another of the first pre-amplifier and the second pre-amplifier.
    Type: Grant
    Filed: September 5, 2017
    Date of Patent: January 29, 2019
    Assignee: NATIONAL TSING HUA UNIVERSITY
    Inventors: Tzu-Hsien Yang, Meng-Fan Chang
  • Patent number: 10186318
    Abstract: A sense amplifier of a resistive memory is controlled by a bit line and a reference line. A voltage sense amplifier has a bit-line input node and a reference input node. A margin enhanced pre-amplifier includes a bit-line two-terminal switching element, a bit-line capacitor, a bit-line three-terminal switching element, a reference two-terminal switching element, a reference capacitor and a reference three-terminal switching element. A read voltage difference between the voltage level of the bit line and the reference line is generated. The bit-line two-terminal switching element, the bit-line three-terminal switching element, the reference two-terminal switching element and the reference three-terminal switching element are synchronizedly switched so as to generate a margin enhanced difference between the voltage level of the bit-line input node and the voltage level of the reference input node. The margin enhanced difference is equal to or greater than three times the read voltage difference.
    Type: Grant
    Filed: March 28, 2018
    Date of Patent: January 22, 2019
    Assignee: NATIONAL TSING HUA UNIVERSITY
    Inventors: Tzu-Hsien Yang, Meng-Fan Chang