Patents by Inventor Mitch Liu

Mitch Liu 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: 8643398
    Abstract: In one embodiment, a core logic section of an integrated circuit is switched to be powered by a standby mode power voltage lower than a normal mode power voltage when the circuit is switched into a standby mode. The standby mode power voltage, however, is too low relative to normal ground to drive a transition logic section of the circuit. A special ground bus is provided in the transition logic section. The special ground bus is pulled down to a voltage below normal ground (i.e., a negative voltage) when the circuit is switched to the standby mode.
    Type: Grant
    Filed: November 19, 2012
    Date of Patent: February 4, 2014
    Assignee: Lattice Semiconductor Corporation
    Inventor: Mitch Liu
  • Patent number: 8314632
    Abstract: A core logic portion of a clocked digital circuit is switched to be powered by a standby mode power voltage lower than a normal mode power voltage when the circuit is switched into a low power standby mode (LPSM). The standby mode power voltage is too low relative to normal ground to deterministically drive a transition logic portion of the circuit. However, a special ground bus (GNDx) is provided in the transition logic portion and that special ground bus (GNDx) is pulled down to a negative voltage below normal ground when the circuit is switched into the low power standby mode (LPSM).
    Type: Grant
    Filed: July 29, 2011
    Date of Patent: November 20, 2012
    Assignee: Lattice Semiconductor Corporation
    Inventor: Mitch Liu
  • Patent number: 7620768
    Abstract: A plurality of memory devices can be erase block tagged in parallel by issuing an erase pulse to memory devices that do not have memory blocks with erase block latches that indicate the block is erased. The status of the memory block is read after the erase pulse. If there are blocks remaining to be erased, erase block tag patterns are generated. Each memory block at a particular sector address has a unique erase block tag pattern to set the erase block latch for that particular memory block. The patterns are transmitted in parallel to the memory devices in a data burst.
    Type: Grant
    Filed: July 10, 2006
    Date of Patent: November 17, 2009
    Assignee: Micron Technology, Inc.
    Inventors: Scott N. Gatzemeier, Mitch Liu
  • Patent number: 7512910
    Abstract: Circuit models for the simulation of charge pumps facilitate design of integrated circuits containing charge pumps. Such models facilitate accurate simulation of actual charge pump behavior without the need to rigorously simulate the multiple capacitive stages of an actual charge pump and the dedicated oscillator clocking the charge pump. The various embodiments utilize a charge pump model having multiple pull-up stages. At lower output voltages, the pull-up stages each provide an output current. These output currents are added together as the output current of the charge pump. Each pull-up stage automatically shuts off when the output voltage approaches a dedicated voltage source for that pull-up stage. As the output voltage increases, less current is output due to the deactivation of pull-up stages.
    Type: Grant
    Filed: December 14, 2005
    Date of Patent: March 31, 2009
    Assignee: Micron Technology, Inc.
    Inventor: Mitch Liu
  • Publication number: 20080144393
    Abstract: A flash memory array includes a reference bit line on which a reference current is imposed. During read operation, bit lines selected for reading are connected to current-to-voltage converters, each of which generates an output voltage based upon the input current flowing in the bit line. The output voltage of the current-to-voltage converter is compared to a reference voltage derived from the output of a reference current-to-voltage converter whose input is driven by a reference current on a reference bit line. Any cell that conducts more current than the reference current will be regarded as an erased cell. Conversely, any cell that conducts less current than the reference current will be regarded as a programmed cell.
    Type: Application
    Filed: February 26, 2008
    Publication date: June 19, 2008
    Applicant: ACTEL CORPORATION
    Inventors: Poongyeub Lee, MingChi Mitch Liu
  • Patent number: 7342832
    Abstract: A flash memory array includes a reference bit line on which a reference current is imposed. During read operation, bit lines selected for reading are connected to current-to-voltage converters, each of which generates an output voltage based upon the input current flowing in the bit line. The output voltage of the current-to-voltage converter is compared to a reference voltage derived from the output of a reference current-to-voltage converter whose input is driven by a reference current on a reference bit line. Any cell that conducts more current than the reference current will be regarded as an erased cell. Conversely, any cell that conducts less current than the reference current will be regarded as a programmed cell.
    Type: Grant
    Filed: November 16, 2005
    Date of Patent: March 11, 2008
    Assignee: Actel Corporation
    Inventors: Poongyeub Lee, MingChi Mitch Liu
  • Publication number: 20070109157
    Abstract: A flash memory array includes a reference bit line on which a reference current is imposed. During read operation, bit lines selected for reading are connected to current-to-voltage converters, each of which generates an output voltage based upon the input current flowing in the bit line. The output voltage of the current-to-voltage converter is compared to a reference voltage derived from the output of a reference current-to-voltage converter whose input is driven by a reference current on a reference bit line. Any cell that conducts more current than the reference current will be regarded as an erased cell. Conversely, any cell that conducts less current than the reference current will be regarded as a programmed cell.
    Type: Application
    Filed: November 16, 2005
    Publication date: May 17, 2007
    Inventors: Poongyueb Lee, MingChi Mitch Liu
  • Publication number: 20060253641
    Abstract: A plurality of memory devices can be erase block tagged in parallel by issuing an erase pulse to memory devices that do not have memory blocks with erase block latches that indicate the block is erased. The status of the memory block is read after the erase pulse. If there are blocks remaining to be erased, erase block tag patterns are generated. Each memory block at a particular sector address has a unique erase block tag pattern to set the erase block latch for that particular memory block. The patterns are transmitted in parallel to the memory devices in a data burst.
    Type: Application
    Filed: July 10, 2006
    Publication date: November 9, 2006
    Inventors: Scott Gatzemeier, Mitch Liu
  • Patent number: 7116584
    Abstract: A plurality of memory devices can be erase block tagged in parallel by issuing an erase pulse to memory devices that do not have memory blocks with erase block latches that indicate the block is erased. The status of the memory block is read after the erase pulse. If there are blocks remaining to be erased, erase block tag patterns are generated. Each memory block at a particular sector address has a unique erase block tag pattern to set the erase block latch for that particular memory block. The patterns are transmitted in parallel to the memory devices in a data burst.
    Type: Grant
    Filed: August 7, 2003
    Date of Patent: October 3, 2006
    Assignee: Micron Technology, Inc.
    Inventors: Scott N. Gatzemeier, Mitch Liu
  • Publication number: 20060106589
    Abstract: Circuit models for the simulation of charge pumps facilitate design of integrated circuits containing charge pumps. Such models facilitate accurate simulation of actual charge pump behavior without the need to rigorously simulate the multiple capacitive stages of an actual charge pump and the dedicated oscillator clocking the charge pump. The various embodiments utilize a charge pump model having multiple pull-up stages. At lower output voltages, the pull-up stages each provide an output current. These output currents are added together as the output current of the charge pump. Each pull-up stage automatically shuts off when the output voltage approaches a dedicated voltage source for that pull-up stage. As the output voltage increases, less current is output due to the deactivation of pull-up stages.
    Type: Application
    Filed: December 14, 2005
    Publication date: May 18, 2006
    Inventor: Mitch Liu
  • Patent number: 7007255
    Abstract: Circuit models for the simulation of charge pumps facilitate design of integrated circuits containing charge pumps. Such models facilitate accurate simulation of actual charge pump behavior without the need to rigorously simulate the multiple capacitive stages of an actual charge pump and the dedicated oscillator clocking the charge pump. The various embodiments utilize a charge pump model having multiple pull-up stages. At lower output voltages, the pull-up stages each provide an output current. These output currents are added together as the output current of the charge pump. Each pull-up stage automatically shuts off when the output voltage approaches a dedicated voltage source for that pull-up stage. As the output voltage increases, less current is output due to the deactivation of pull-up stages.
    Type: Grant
    Filed: February 27, 2003
    Date of Patent: February 28, 2006
    Assignee: Micron Technology, Inc.
    Inventor: Mitch Liu
  • Publication number: 20050033904
    Abstract: A plurality of memory devices can be erase block tagged in parallel by issuing an erase pulse to memory devices that do not have memory blocks with erase block latches that indicate the block is erased. The status of the memory block is read after the erase pulse. If there are blocks remaining to be erased, erase block tag patterns are generated. Each memory block at a particular sector address has a unique erase block tag pattern to set the erase block latch for that particular memory block. The patterns are transmitted in parallel to the memory devices in a data burst.
    Type: Application
    Filed: August 7, 2003
    Publication date: February 10, 2005
    Inventors: Scott Gatzemeier, Mitch Liu
  • Patent number: 6842371
    Abstract: A master block lock control word is written to a mini array of non-volatile fuses. The control word is recalled and decoded. A successful recall of the control word generates an indication that the master block lock bit is permanently disabled from subsequent changes.
    Type: Grant
    Filed: June 3, 2003
    Date of Patent: January 11, 2005
    Assignee: Micron Technology, Inc.
    Inventor: Mitch Liu
  • Publication number: 20040246781
    Abstract: A master block lock control word is written to a mini array of non-volatile fuses. The control word is recalled and decoded. A successful recall of the control word generates an indication that the master block lock bit is permanently disabled from subsequent changes.
    Type: Application
    Filed: June 3, 2003
    Publication date: December 9, 2004
    Inventor: Mitch Liu
  • Publication number: 20040172604
    Abstract: Circuit models for the simulation of charge pumps facilitate design of integrated circuits containing charge pumps. Such models facilitate accurate simulation of actual charge pump behavior without the need to rigorously simulate the multiple capacitive stages of an actual charge pump and the dedicated oscillator clocking the charge pump. The various embodiments utilize a charge pump model having multiple pull-up stages. At lower output voltages, the pull-up stages each provide an output current. These output currents are added together as the output current of the charge pump. Each pull-up stage automatically shuts off when the output voltage approaches a dedicated voltage source for that pull-up stage. As the output voltage increases, less current is output due to the deactivation of pull-up stages.
    Type: Application
    Filed: February 27, 2003
    Publication date: September 2, 2004
    Applicant: Micron Technology, Inc.
    Inventor: Mitch Liu