Patents by Inventor Todd Merritt

Todd Merritt 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: 6664634
    Abstract: A memory integrated circuit having three layers of metallic traces disposed over a substrate assembly including various active devices. The traces are arranged to include I/O traces that are continuous in the third layer across spans of 4 or 8 memory blocks of an array, and that are interspersed on the third layer with non-I/O lines adapted to reduce interference between I/O lines. Column select lines, orthogonal to I/O lines and disposed in the third layer of metallic traces, except in the vicinity of I/O lines, are provided in a linear configuration and shielded from parallel digit lines in the first layer of traces by traces of the intervening second layer of traces. Global bleeder lines disposed in the third layer of traces are adapted to apply a standby voltage to a plurality of sense amplifiers. Other features of the invention include two layer power and ground bus traces, and row decoder and phase driver circuits disposed in throat and gap cell regions respectively.
    Type: Grant
    Filed: March 15, 2001
    Date of Patent: December 16, 2003
    Assignee: Micron Technology, Inc.
    Inventors: J. Wayne Thompson, Todd A. Merritt
  • Patent number: 6654306
    Abstract: An apparatus and method for generating a plurality of output signals that can be used for driving a corresponding plurality of charge pumps from a signal oscillating between a first and second logic state. The apparatus includes a plurality of shift register stages coupled in series, where the shift register stages shift a latched logic state in response to the oscillating signal. Further included in the apparatus is a duty cycle correcting circuit coupled to the output terminals of the shift register stages which generates each of the output signals that can be used to drive a charge pump based on the latched logic state of two of the shift register stages.
    Type: Grant
    Filed: January 7, 2003
    Date of Patent: November 25, 2003
    Assignee: Micron Technology, Inc.
    Inventors: Todd A. Merritt, Hal W. Butler
  • Patent number: 6615325
    Abstract: An integrated circuit memory device is designed for high speed data access and for compatibility with existing memory systems. An address strobe signal is used to latch a first address. During a burst access cycle the address is incremented internal to the device with additional address strobe transitions. A new memory address is only required at the beginning of each burst access. Read/Write commands are issued once per burst access eliminating the need to toggle the Read/Write control line at the device cycle frequency. Transitions of the Read/Write control line during a burst access will terminate the burst access, reset the burst length counter and initialize the device for another burst access. The device is compatible with existing Extended Data Out DRAM device pinouts, Fast Page Mode and Extended Data Out Single In-Line Memory Module pinouts, and other memory circuit designs.
    Type: Grant
    Filed: December 3, 1997
    Date of Patent: September 2, 2003
    Assignee: Micron Technology, Inc.
    Inventors: Jeffrey S. Mailloux, Kevin J. Ryan, Todd A. Merritt, Brett L. Williams
  • Patent number: 6587978
    Abstract: The invention is a dynamic random access memory (DRAM) device having an electronic test key fabricated on board and is a method for testing the DRAM. The electronic test key generates a signal which effects a variation in a pulse width of an internal control signal to stress the DRAM during a test mode.
    Type: Grant
    Filed: February 20, 1996
    Date of Patent: July 1, 2003
    Assignee: Micron Technology, Inc.
    Inventors: Todd A. Merritt, George B. Raad, Stephen L. Casper
  • Patent number: 6578165
    Abstract: An internal guardband for use in semiconductor testing is disclosed. One aspect of the invention is a semiconductor circuit having two paths. The first path is a standard path, used for normal operation of the circuit. The second path is a test path, used for testing of the circuit. The second, test path adds delay as compared to the first, standard path. This delay acts as an internal guardband for the circuit.
    Type: Grant
    Filed: August 30, 2001
    Date of Patent: June 10, 2003
    Assignee: Micron Technology, Inc.
    Inventor: Todd A. Merritt
  • Patent number: 6577552
    Abstract: An apparatus and method for generating a plurality of output signals that can be used for driving a corresponding plurality of charge pumps from a signal oscillating between a first and second logic state. The apparatus includes a plurality of shift register stages coupled in series, where the shift register stages shift a latched logic state in response to the oscillating signal. Further included in the apparatus is a duty cycle correcting circuit coupled to the output terminals of the shift register stages which generates each of the output signals that can be used to drive a charge pump based on the latched logic state of two of the shift register stages.
    Type: Grant
    Filed: August 30, 2001
    Date of Patent: June 10, 2003
    Assignee: Micron Technology, Inc.
    Inventors: Todd A. Merritt, Hal W. Butler
  • Publication number: 20030094997
    Abstract: A voltage pump and method of driving a node to an increased potential. A periodic input signal is fed into a precharged small capacitor to create a level shifted periodic intermediate potential at an intermediate node. The intermediate node is a supply node to a level translator circuit The output of the level translator circuit controls the actuation of a pass transistor. When actuated the pass transistor drives a boosted potential to an output node of the voltage pump circuit. In one embodiment the level translator circuit has a delay element which maintains the deactivation of a pull down portion of the level translator circuit until a pull up portion of the level translator circuit is deactivated. A first diode clamp is used to limit the output of the level translator circuit and the boosted potential to within 1 threshold voltage (of the diode clamp) of each other.
    Type: Application
    Filed: January 7, 2003
    Publication date: May 22, 2003
    Applicant: Micron Technology, Inc.
    Inventors: Greg A. Blodgett, Todd A. Merritt
  • Publication number: 20030095461
    Abstract: An apparatus and method for generating a plurality of output signals that can be used for driving a corresponding plurality of charge pumps from a signal oscillating between a first and second logic state. The apparatus includes a plurality of shift register stages coupled in series, where the shift register stages shift a latched logic state in response to the oscillating signal. Further included in the apparatus is a duty cycle correcting circuit coupled to the output terminals of the shift register stages which generates each of the output signals that can be used to drive a charge pump based on the latched logic state of two of the shift register stages.
    Type: Application
    Filed: January 7, 2003
    Publication date: May 22, 2003
    Inventors: Todd A. Merritt, Hal W. Butler
  • Patent number: 6560728
    Abstract: The present invention reduces the area on a die required for rows and columns of redundant memory cells by sharing compare circuitry with banks of redundant memory cells based on division of the primary memory array into two or more “planes.” Pass gates or multiplexers coupled between at least two banks of fuses and one compare circuit selectively couple the appropriate fuse bank to the compare circuit. Preferably, a bit in the address (e.g., address bit RA9 in a row address word having address bits A0-RA9) is received by and controls the multiplexer to select between the two banks of fuses. Additionally, the planes span blocks of memory in the memory array, where each block is divided by shared sense amplifiers. As a result, while eight lines are coupled to 16 rows or columns, only eight rows or columns will be active at any one time because isolation gates will enable only eight of the 16 rows or columns within two planes of memory.
    Type: Grant
    Filed: December 19, 2000
    Date of Patent: May 6, 2003
    Assignee: Micron Technology, Inc.
    Inventor: Todd A. Merritt
  • Patent number: 6556643
    Abstract: An improved DDLL containing a majority filter counter circuit is disclosed. The majority filter counter circuit is located between the phase detector and the shift register of the DDLL. The majority filter counter circuit receives shifting commands from the phase detector and filters the shift commands from reaching the shift register until a predetermined number (e.g., 16) have been received from the phase detector before transmitting a shift command (either shift right or shift left) to the shift register. Once the shift register receives the shift command, the shift register directs the delay line to shift by one tap in either a shift right or a shift left direction depending upon the phase relationship between CLKIn and CLKOut. By waiting for e.g., 16 shift commands, the majority filter counter circuit ensures that a premature shift command is not delivered to the shift register in the case of a noise event.
    Type: Grant
    Filed: August 27, 2001
    Date of Patent: April 29, 2003
    Assignee: Micron Technology, Inc.
    Inventor: Todd Merritt
  • Publication number: 20030067817
    Abstract: An integrated circuit memory device is designed to perform high speed data write cycles. An address strobe signal is used to latch a first address. During a burst access cycle the address is incremented internal to the device with additional address strobe transitions. A new memory address is only required at the beginning of each burst access. Read/Write commands are issued once per burst access eliminating the need to toggle the Read/Write control line at the device cycle frequency. A transition of the Read/Write control line during a burst access is used to terminate the burst access and initialize the device for another burst access. Write cycle times are maximized to allow for increases in burst mode operating frequencies. Local logic gates near array sense amplifiers are used to control write data drivers to provide for maximum write times without crossing current during input/output line equilibration periods.
    Type: Application
    Filed: August 29, 2002
    Publication date: April 10, 2003
    Applicant: Micron Technology, Inc.
    Inventors: Todd A. Merritt, Troy A. Manning
  • Patent number: 6545894
    Abstract: In a semiconductor memory device, a die architecture is provided that arranges memory arrays into a long, narrow configuration. Bond pads may then be placed along a long side of a correspondingly shaped die. As a result, this architecture is compatible with short lead frame “fingers” for use with wide data busses as part of high speed, multiple band memory integrated circuits.
    Type: Grant
    Filed: December 11, 2001
    Date of Patent: April 8, 2003
    Assignee: Micron Technology, Inc.
    Inventors: Donald M. Morgan, Todd A. Merritt
  • Publication number: 20030063502
    Abstract: An integrated circuit memory device is designed to perform high speed data write cycles. An address strobe signal is used to latch a first address. During a burst access cycle the address is incremented internal to the device with additional address strobe transitions. A new memory address is only required at the beginning of each burst access. Read/Write commands are issued once per burst access eliminating the need to toggle the Read/Write control line at the device cycle frequency. A transition of the Read/Write control line during a burst access is used to terminate the burst access and initialize the device for another burst access. Write cycle times are maximized to allow for increases in burst mode operating frequencies. Local logic gates near array sense amplifiers are used to control write data drivers to provide for maximum write times without crossing current during input/output line equilibration periods.
    Type: Application
    Filed: August 29, 2002
    Publication date: April 3, 2003
    Applicant: Micron Technology, Inc.
    Inventors: Todd A. Merritt, Troy A. Manning
  • Patent number: 6535999
    Abstract: A method and apparatus that tests and observes how an embedded DRAM is being accessed by a logic circuit controlling the DRAM is provided. The test and observe method and apparatus pipes the outputs of the logic, which is used as inputs to the embedded DRAM, to an observation device. The outputs of the logic device are then observed at the observation device to determine how the DRAM is being accessed. In addition, information concerning what data is being trapped and when may be output to the observation device to determine setup and hold times for the DRAM.
    Type: Grant
    Filed: July 13, 1999
    Date of Patent: March 18, 2003
    Assignee: Micron Technology, Inc.
    Inventors: Todd A. Merritt, Nick Van Heel
  • Publication number: 20030043644
    Abstract: An apparatus and method for generating a plurality of output signals that can be used for driving a corresponding plurality of charge pumps from a signal oscillating between a first and second logic state. The apparatus includes a plurality of shift register stages coupled in series, where the shift register stages shift a latched logic state in response to the oscillating signal. Further included in the apparatus is a duty cycle correcting circuit coupled to the output terminals of the shift register stages which generates each of the output signals that can be used to drive a charge pump based on the latched logic state of two of the shift register stages.
    Type: Application
    Filed: August 30, 2001
    Publication date: March 6, 2003
    Inventors: Todd A. Merritt, Hal W. Butler
  • Patent number: 6529426
    Abstract: The invention is a dynamic random access memory (DRAM) device having an electronic test key fabricated on board and is a method for testing the DRAM. The electronic test key generates a signal which effects a variation in a period of an internal control signal to stress the DRAM during a test mode.
    Type: Grant
    Filed: January 28, 1997
    Date of Patent: March 4, 2003
    Assignee: Micron Technology, Inc.
    Inventors: Todd A. Merritt, Paul S. Zagar
  • Publication number: 20030038662
    Abstract: An improved DDLL containing a majority filter counter circuit is disclosed. The majority filter counter circuit is located between the phase detector and the shift register of the DDLL. The majority filter counter circuit receives shifting commands from the phase detector and filters the shift commands from reaching the shift register until a predetermined number (e.g., 16) have been received from the phase detector before transmitting a shift command (either shift right or shift left) to the shift register. Once the shift register receives the shift command, the shift register directs the delay line to shift by one tap in either a shift right or a shift left direction depending upon the phase relationship between CLKIn and CLKOut. By waiting for e.g., 16 shift commands, the majority filter counter circuit ensures that a premature shift command is not delivered to the shift register in the case of a noise event.
    Type: Application
    Filed: August 27, 2001
    Publication date: February 27, 2003
    Inventor: Todd Merritt
  • Patent number: 6525971
    Abstract: An integrated circuit memory device is designed to perform high speed data write cycles. An address strobe signal is used to latch a first address. During a burst access cycle the address is incremented internal to the device with additional address strobe transitions. A new memory address is only required at the beginning of each burst access. Read/Write commands are issued once per burst access eliminating the need to toggle the Read/Write control line at the device cycle frequency. A transition of the Read/Write control line during a burst access is used to terminate the burst access and initialize the device for another burst access. Write cycle times are maximized to allow for increases in burst mode operating frequencies. Local logic gates near array sense amplifiers are used to control write data drivers to provide for maximum write times without crossing current during input/output line equilibration periods.
    Type: Grant
    Filed: July 27, 1999
    Date of Patent: February 25, 2003
    Assignee: Micron Technology, Inc.
    Inventors: Todd A. Merritt, Troy A. Manning
  • Patent number: 6504743
    Abstract: In a semiconductor memory device, a die architecture is provided that arranges memory arrays into a long, narrow configuration. Bond pads may then be placed along a long side of a correspondingly shaped die. As a result, this architecture is compatible with short lead frame “fingers” for use with wide data busses as part of high speed, multiple band memory integrated circuits.
    Type: Grant
    Filed: November 7, 2001
    Date of Patent: January 7, 2003
    Assignee: Micron Technology, Inc.
    Inventors: Donald M. Morgan, Todd A. Merritt
  • Patent number: RE38109
    Abstract: A block write circuit in a memory device having a wide internal data path performs block write and data masking functions. The memory device includes a plurality of data terminals adapted to receive respective data signals, and a plurality of array groups each including a plurality of arrays and each array includes a plurality of memory cells. A plurality of input/output line groups each include a plurality of input/output lines coupled to the arrays of an associated array group. The block write circuit comprises a plurality of write driver groups, each write driver group including a plurality of write driver circuits having outputs coupled to respective data lines in an associated data line group. Each write driver circuit includes an input and develops a data signal on its output responsive to a data signal applied on its input. A multiplexer circuit includes a plurality of inputs coupled to respective data terminals, and a plurality of output subgroups.
    Type: Grant
    Filed: December 20, 2001
    Date of Patent: May 6, 2003
    Assignee: Micron Technology, Inc.
    Inventors: Todd A. Merritt, Layne Bunker