Patents Assigned to Lattice Semiconductor Corporation
  • Patent number: 7348914
    Abstract: Systems and methods are disclosed herein to provide improved alignment of output signals of an analog-to-digital converter (ADC). For example, in accordance with an embodiment of the present invention, a method of aligning digital signals appearing on signal paths of a parallel data bus includes sampling the digital signals at a plurality of delay times to obtain a plurality of sample sets, wherein each sample set is associated with a corresponding delay time. A second digital signal that is misaligned with respect to a first digital signal is identified from the sample sets. The delay time required to align the second digital signal with the first digital signal is determined. The delay of the second digital signal is adjusted by the determined delay time.
    Type: Grant
    Filed: June 29, 2006
    Date of Patent: March 25, 2008
    Assignee: Lattice Semiconductor Corporation
    Inventors: Asher Hazanchuk, Ian Ing, Satwant Singh
  • Patent number: 7342846
    Abstract: Systems and methods provide improved address decoding techniques for memory. For example, in accordance with an embodiment of the present invention, an integrated circuit includes an address register that receives a reset signal, a clock signal, and an address signal and provides a registered address signal. The registered address signal provides at least a true and a complement signal, with the true and complement signal set to approximately the same logical value upon assertion of the reset signal. An address pre-decoder, coupled to the address register, at least partially decodes the registered address signal to provide a pre-decoded output signal. A wordline driver, coupled to the address pre-decoder, receives a wordline enable signal and the pre-decoded output signal and provides a wordline signal based on the pre-decoded output signal upon assertion of the wordline enable signal.
    Type: Grant
    Filed: July 22, 2005
    Date of Patent: March 11, 2008
    Assignee: Lattice Semiconductor Corporation
    Inventors: Louis De La Cruz, Allen R. White, Hemanshu T. Vernenker
  • Patent number: 7342838
    Abstract: Within a programmable logic device (PLD), a DDR SDRAM interface for a DDR SDRAM is provided, the DDR SDRAM providing data to the PLD on the rising and falling edges of a DQS signal, the interface including: a first register adapted to capture data associated with the falling edges of the DQS signal; a second register adapted to capture data associated with the rising edges of the DQS signal; and clock edge selection logic circuitry coupled to clock inputs of the first and second registers and adapted to select between the rising or falling clock edges of an internal PLD clock to clock the first and second registers and thereby transfer the captured data into core logic for the PLD, the selection of the clock edge based on a phase relationship between the internal PLD clock and the DQS signal.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: March 11, 2008
    Assignee: Lattice Semiconductor Corporation
    Inventors: Brad Sharpe-Geisler, Om P. Agrawal, Kiet Truong, Giap Tran, Bai Nguyen
  • Patent number: 7339952
    Abstract: A pointer processing method, in which a pointer value is converted into the corresponding row and column numbers identifying the position of a synchronous payload envelope (SPE) within a data frame. In certain embodiments of the invention, the row number is obtained from the pointer value using a single comparison operation. This is accomplished by using a truncated pointer value to identify the location of the first byte of the SPE envelope to within at most two adjacent rows. The actual row number can then be determined by comparing the full pointer value with a boundary value corresponding to the two identified rows.
    Type: Grant
    Filed: March 12, 2003
    Date of Patent: March 4, 2008
    Assignee: Lattice Semiconductor Corporation
    Inventor: Umesh Ananthiah
  • Patent number: 7327159
    Abstract: In accordance with an embodiment of the present invention, a programmable logic device includes a memory adapted to store information in the programmable logic device, an input/output circuit adapted to transfer information into or out of the programmable logic device, and an interconnect architecture adapted to route information within the programmable logic device. An interface circuit is provided to couple the memory and the input/output circuit to the interconnect architecture.
    Type: Grant
    Filed: November 28, 2005
    Date of Patent: February 5, 2008
    Assignee: Lattice Semiconductor Corporation
    Inventors: Om P. Agrawal, Ravindar M. Lall, David L. Rutledge, Tom Gustafson
  • Patent number: 7327160
    Abstract: In one embodiment of the invention, a programmable integrated circuit includes a plurality of SERDES circuits; a plurality of input/output (I/O) circuits; and a routing structure configurable to provide one or more of the following connections over routing paths having deterministic routing delays: coupling a SERDES circuit to another SERDES circuit; coupling a SERDES circuit to an I/O circuit; coupling an I/O circuit to a SERDES circuit; and coupling an I/O circuit to another I/O circuit.
    Type: Grant
    Filed: February 16, 2007
    Date of Patent: February 5, 2008
    Assignee: Lattice Semiconductor Corporation
    Inventors: Om P. Agrawal, Jock Tomlinson, Kuang Chi, Ji Zhao, Ju Shen, Jinghui Zhu
  • Patent number: 7317343
    Abstract: In one embodiment of the invention, a pulse-generation circuit for generating control signals has clock-delay circuitry for generating a plurality of differently delayed clock signals. Each control signal is generated by a set-reset latch that receives its set and reset signals from different pulse generators operating based on different delayed clock signals from the clock-delay circuitry. In one implementation, the clock-delay circuitry has a partitioned delay block in which different sub-blocks provide different delay functionality to provide the clock-delay circuitry with programmable flexibility.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: January 8, 2008
    Assignee: Lattice Semiconductor Corporation
    Inventors: Louis De La Cruz, Hemanshu T. Vernenker
  • Patent number: 7313025
    Abstract: Systems and methods are disclosed herein to provide improved verification of flash memory erasure. For example, in accordance with an embodiment of the present invention, an integrated circuit includes an array of flash memory cells. A plurality of sense amplifiers are also provided wherein each sense amplifier is associated with a plurality of the flash memory cells and adapted to detect a state of one of the associated flash memory cells selected from the plurality of flash memory cells. A first logic circuit is also provided to receive the states of the selected flash memory cells from the sense amplifiers and perform a first logic operation at approximately the same time on the states to verify that all states of the selected flash memory cells correspond to an erased state.
    Type: Grant
    Filed: February 15, 2007
    Date of Patent: December 25, 2007
    Assignee: Lattice Semiconductor Corporation
    Inventors: Hok Wong, Fabiano Fontana
  • Patent number: 7307319
    Abstract: A high-voltage circuit protection device includes a p-n junction in a semiconductor substrate that is spaced apart from a first electrode region by a diode region. A semiconductor layer overlies the diode region and is separated therefrom by a dielectric layer. A shallow-doped region resides in the diode region spaced apart from the p-n junction by a predetermined distance. The predetermined distance preferably ranges from about 0 to about 50% of the length of the diode region. A process for fabricating the high-voltage device includes forming the shallow-doped region using a threshold adjustment mask followed by formation of the first electrode region using the semiconductor layer in a self-aligned doping process. The shallow-doped region functions to reduce the clamping voltage of the device.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: December 11, 2007
    Assignee: Lattice Semiconductor Corporation
    Inventors: Nui Chong, Farrokh Omid-Zohoor
  • Patent number: 7307912
    Abstract: Systems and methods disclosed herein provide for variable data width memory. For example, in accordance with an embodiment of the present invention, a technique for doubling a width of a memory is disclosed, without having to increase a width of the internal data path or the number of input/output pads.
    Type: Grant
    Filed: October 25, 2004
    Date of Patent: December 11, 2007
    Assignee: Lattice Semiconductor Corporation
    Inventors: Hemanshu T. Vernenker, Margaret C. Tait, Christopher Hume, Nhon Nguyen, Allen White, Tim Swensen, Sam Tsai, Steve Eplett
  • Patent number: 7304863
    Abstract: An integrated circuit package can include electronic components used to enhance the performance of the integrated circuit that is part of the package. In order to reduce some adverse effects of including the electronic components, void regions are introduced into portions of the integrated circuit package interconnect layers.
    Type: Grant
    Filed: June 9, 2003
    Date of Patent: December 4, 2007
    Assignee: Lattice Semiconductor Corporation
    Inventor: Weijia Wu
  • Patent number: 7305047
    Abstract: A receiver for high-speed serial communication that uses an interface such as XAUI is disclosed with automatic lane assignment. The receiver analyzes incoming data packets and determines the lanes based on the data packets. The lanes are then automatically reordered. The receiver allows the lanes to be connected to the receiver arbitrarily, thereby providing additional layout freedom to circuit board and ASIC designers.
    Type: Grant
    Filed: March 12, 2003
    Date of Patent: December 4, 2007
    Assignee: Lattice Semiconductor Corporation
    Inventor: Edward James Turner
  • Patent number: 7301996
    Abstract: The skew between a received clock signal and a received data signal that are source synchronous, is accounted for such that stable bit values of the received data signal may be sampled. For programmable skew cancellation, a skew value corresponding to the amount of the skew is determined and programmed into a data storage device. Sampling clock signals of the same frequency but different phases are generated from the clock signal, and one of the sampling clock signals having the desired phase is selected depending on the programmed skew value. Alternatively, for automatic skew cancellation, a phase locked loop compares the received data signal to one of the sampling clock signals to determine the skew value for selecting the sampling clock signal having the desired phase. Stable bit values of the data signal are then sampled with the selected sampling clock signal.
    Type: Grant
    Filed: May 28, 2003
    Date of Patent: November 27, 2007
    Assignee: Lattice Semiconductor Corporation
    Inventors: Kuang-Kai Chi, Ju-Young Lee, Zhi-Min Qi, Dah-Shi Shen
  • Patent number: 7301182
    Abstract: In one embodiment, a circuit may be formed by forming at least one bent-gate output stage transistor and at least one bent-gate input stage transistor. The bent-gate output stage transistor may be electrically isolated from an input to the bent-gate input stage transistor by forming at least one bent-gate grounded-gate transistor between the bent-gate output stage transistor and the input to the bent-gate input stage transistor.
    Type: Grant
    Filed: September 13, 2005
    Date of Patent: November 27, 2007
    Assignee: Lattice Semiconductor Corporation
    Inventors: Larry Metzger, Kerry Ilgenstein, Sunil Mehta
  • Patent number: 7295035
    Abstract: In one embodiment of the invention, a programmable logic block within a programmable logic device includes: a plurality of lookup tables, each lookup table providing a combinatorial output signal; and a plurality of registers, each register being adapted to register a selected one of the combinatorial output signals, wherein the number of registers is less than the number of lookup tables.
    Type: Grant
    Filed: August 9, 2005
    Date of Patent: November 13, 2007
    Assignee: Lattice Semiconductor Corporation
    Inventors: Om Agrawal, Manish Garg, Chan-Chi Jason Cheng, Satwant Singh, Ju Shen
  • Patent number: 7269771
    Abstract: A device includes data input and data output pins such as found in a JTAG port and a first plurality of boundary scan cells. The device is configurable to support a secondary boundary scan cells formed from the first plurality of boundary scan cells and a second plurality of boundary scan cells in at least one external device. In one embodiment, the device includes a demultiplexer which may be configured to support a primary boundary scan chain between the JTAG port and the first plurality of boundary scan cells. The demultiplexer may also be configured to support the secondary boundary scan chain between the JTAG port and the first and the second plurality of boundary scan cells.
    Type: Grant
    Filed: September 30, 2003
    Date of Patent: September 11, 2007
    Assignee: Lattice Semiconductor Corporation
    Inventors: Daniel B. Young, Jeffrey S. Byrne
  • Patent number: 7265578
    Abstract: A first programmable device comprises non-dedicated, programmable resources including programmable logic; dedicated circuitry; a Joint Test Action Group (JTAG) interface adapted to selectively interchange signals with the programmable logic via the dedicated circuitry; and a Serial Peripheral Interface (SPI) interface adapted to (1) selectively interchange signals with the programmable logic via the dedicated circuitry and (2) selectively interchange signals with the JTAG interface via the dedicated circuitry. The JTAG interface is adapted to be connected to a first external device. The SPI interface is adapted to be connected to a second external device. The first programmable device is adapted to transfer signals from the first external device to the second external device via the JTAG interface, the dedicated circuitry, and the SPI interface without relying on any of the programmable resources.
    Type: Grant
    Filed: April 4, 2005
    Date of Patent: September 4, 2007
    Assignee: Lattice Semiconductor Corporation
    Inventors: Howard Tang, Satwant Singh, San-Ta Kow
  • Patent number: 7263024
    Abstract: In one embodiment of the invention, an address decoder for decoding a word-line address to energize a word line in a block of computer memory. Instead of relying on a distinct enable signal, a clock signal provides a reset function and an enable function to the address decoder. In one implementation, the address decoder includes negative-level-sense latches and 3-input AND gates to generate decoded address bits. Using the clock signal as one of the inputs to the AND gates ensures that all of the decoded address bits are 0 when the clock signal is low and that exactly one decoded address bit is 1 when the clock signal is high. In this way, the address decoder ensures that two or more word lines are not energized at the same time.
    Type: Grant
    Filed: October 17, 2005
    Date of Patent: August 28, 2007
    Assignee: Lattice Semiconductor Corporation
    Inventor: Larry R. Fenstermaker
  • Patent number: 7262630
    Abstract: In one embodiment of the invention, a programmable termination structure has first and second termination circuits for corresponding pads and a programmable connection therebetween. The first termination circuit supports first and second sets of termination schemes. A shared resistor is part of at least one termination scheme in each set. The first termination circuit supports a termination scheme between the first pad and a user-defined node connected to an on-chip capacitor such that first pad is connected via the termination scheme to the on-chip capacitor. Control circuitry automatically turns on and off a termination scheme for bidirectional signaling supported by the first termination circuit, wherein (1) the control circuitry turns off the termination scheme if an output buffer is configured to present outgoing signals at the first pad and (2) the control circuitry turns on the termination scheme if the output buffer is disabled in order to terminate incoming signals received at the first pad.
    Type: Grant
    Filed: August 1, 2005
    Date of Patent: August 28, 2007
    Assignee: Lattice Semiconductor Corporation
    Inventors: William B. Andrews, Barry K. Britton, John Schadt, Mou C. Lin
  • Patent number: 7257750
    Abstract: In one embodiment, a programmable logic device is provided that includes a memory having memory cells, each memory cell operable to store either a configuration bit or a RAM bit; a masking circuit operable to mask a RAM bit by providing a masking value for the masked RAM bit; an error detection circuit operable to process the configuration bits during operation of the programmable logic device using an error detection algorithm, the error detection circuit calculating a signature that includes configuration bits and masking values; and a comparator operable to compare the signature calculated by the error detection circuit with a correct signature.
    Type: Grant
    Filed: January 13, 2005
    Date of Patent: August 14, 2007
    Assignee: Lattice Semiconductor Corporation
    Inventors: Satwant Singh, Chi Nguyen, Ann Wu, Ting Yew