Abstract: Clock generators include phase-locked and delay-locked loop integrated circuits that support efficient high speed testing of clock frequencies. An integrated circuit device is provided with a clock signal generator having at least one delay element therein that is responsive to a control signal. A speed tracking circuit is also provided. This speed tracking circuit is configured to generate a signal having a measurable characteristic that tracks changes in a property of the control signal that influences a delay of the at least one delay element.
Abstract: A method for determining photoresist thickness is disclosed that can be used in a semiconductor fabrication process. A layer of material is formed that has one or more common characteristic relative to the material in the layer that is to be patterned in the semiconductor fabrication process. A layer of photoresist is then formed that has varying thickness. The thickness of the layer of photoresist is determined at a plurality of different points. The layer of photoresist is exposed, developed and etched. The remaining structures are then analyzed to determine photoresist thickness to be used in the semiconductor fabrication process. The determined photoresist thickness is then used in the semiconductor fabrication process to form structures on a semiconductor wafer.
Abstract: A reset circuit for resetting two clock domains resets the two clock domains synchronously with a first clock signal in response to assertion of a system reset. It then de-asserts the resetting of a first of the clock domains in synchronization with the first clock signal, and de-asserts the resetting of a second of the clock domains in synchronization with a second clock signal so that the second clock domain is not operative until after the second clock signal is running.
Abstract: A high speed MOSFET output driver is disclosed that includes a voltage level shifter stage operable to transition an input signal at a first voltage level to an output signal at a second voltage level, an output stage operable to drive high voltage output load, and a hot inverter, biased between the second voltage level and the bias voltage such that the voltage gain of the output signal is increased and at the same time the minimum voltage level of the output signal introduced to the output stage is decreased, improving the control and the transition time of the output signal and allowing all components of the high speed MOSFET output driver of the present invention to be fabricated using a single thin gate oxide process.
Abstract: In accordance with the invention, a driver circuit is described that permits a single thin gate oxide process to be utilized where a dual oxide process may normally be necessary. Circuits employing only thin gate oxide devices are used as the design basis for a single product with a single set of tooling and manufacturing process to operate within the same timing specifications for a core voltage output drive as well as for a higher system drive.
Type:
Grant
Filed:
December 9, 2004
Date of Patent:
May 29, 2007
Assignee:
Integrated Device Technology, Inc.
Inventors:
David Pilling, Kar-chung Leo Lee, Mario Fulam Au
Abstract: The present invention includes SRAM memory cells and methods for forming SRAM cells having reduced soft error rate. The SRAM cell includes a first NMOS transistor and a first PMOS transistor having a common gate, and a second NMOS transistor and a second PMOS transistor having a common gate. A first resistor is electrically coupled on one end to the drains of the first PMOS transistor and the first NMOS transistor; and is electrically coupled on the other end to the common gate of the second NMOS and second PMOS transistors. A second resistor is electrically coupled on one end to the drains of the second PMOS transistor and the second NMOS transistor; and is electrically coupled on the other end to the common gate of the first NMOS transistor and the first PMOS transistor. The added resistor can be embedded in a contact opening such that it does not take up valuable surface area on the semiconductor substrate. Thereby, data loss from soft errors can be avoided while preserving small memory cell size.
Type:
Grant
Filed:
February 22, 2005
Date of Patent:
May 8, 2007
Assignee:
Integrated Device Technology, Inc.
Inventors:
Shih-Ked Lee, Chuen-Der Lien, Louis Huang, Gaolong Jin, Wanqing Cao, Guo-Qiang Lo
Abstract: FIFO memory devices are configured to support a pair of hybrid operating modes that enable the FIFO memory device to be depth-expandable with other FIFO memory devices in a collective standard mode of operation. The pair of hybrid operating modes including a first hybrid mode that supports a write interface configured in standard mode and a read interface configured in first-word fall-through (FWFT) mode and a second hybrid mode that supports a write interface configured in FWFT mode and a read interface configured in standard mode.
Type:
Grant
Filed:
November 24, 2003
Date of Patent:
April 24, 2007
Assignee:
Integrated Device Technology, Inc.
Inventors:
Mario Au, Jiann-Jeng Duh, Tze-yuan Fang
Abstract: A content matching engine (CME) uses a content addressable memory (CAM) array that stores a plurality of strings in separate entries. The strings define one or more rules to be matched. The strings of each rule are linked, thereby providing a required order. The strings of each rule can be linked by per-entry counters associated with each string, or by a state machine. The strings in the CAM array are compared with a packet, which is shifted one symbol at a time (because the strings can start on any boundary). When the CAM detects a match, the CAM skips over the string that resulted in the match, thereby preventing erroneous matches. The CAM allows parallel matching to be performed for multiple rules. If the contents of a packet match all of the strings of a rule, in order, then the CME asserts a match/index signal that identifies the matched rule.
Abstract: A network switch port receives, stores and then forwards incoming cells. The network switch assigns each incoming cell to one of a set of flow queues, each of which is allotted a portion of space in a cell memory. The switch port periodically computes a average of the number of cells assigned to each flow queue stored in the cell memory during a preceding period, and assigns a discard weight to each incoming cell that is a function of the amount by which the average for the cell's assigned flow queue exceeds a threshold level. The switch port randomly discards incoming cells assigned to the flow queue with a probability that increases with the incoming cells' assigned weights. The switch port stores incoming cells that are not randomly discarded in the cell memory and later forewords them from the cell memory.
Abstract: An integrated circuit delay device includes a digital delay line configured to provide a percent-of-clock period delay to a timing signal received at an input thereof, in response to a control signal. This control signal has a value that specifies a length of the delay. A delay line control circuit is also provided. The delay line control circuit is configured to generate the control signal by counting multiple cycles of a high frequency oscillator signal (e.g., ring oscillator signal) having a period less than the clock period, over a time interval having a duration greater than the clock period.
Type:
Grant
Filed:
May 23, 2005
Date of Patent:
April 10, 2007
Assignee:
Integrated Device Technology, Inc.
Inventors:
Robert J. Proebsting, Cesar A. Talledo, David J. Pilling
Abstract: A packaged integrated circuit device includes a nonvolatile memory device and a programmable clock driver circuit therein. The memory device may be provided as an EEPROM device that is disposed on a first integrated circuit substrate and the programmable clock driver circuit may be disposed on a second integrated circuit substrate. The programmable clock driver circuit includes a control circuit and a clock generator therein. The control circuit is configured to detect an error(s) in configuration data that is used by the programmable clock driver circuit. This configuration data is read from the nonvolatile memory and stored in volatile program registers during program restore operations. The control circuit is further configured to automatically idle the clock generator in response to detecting the error in the configuration data. This automatic idling of the clock generator may include operations to set the clock generator at a default setting (e.g.
Type:
Grant
Filed:
November 3, 2004
Date of Patent:
March 27, 2007
Assignee:
Integrated Device Technology, Inc.
Inventors:
Bradley C. Luis, Roland T. Knaack, Srinivas S. B. Bamdhamravuri
Abstract: A method and structure for cutting a ring current when a telephone enters an off-hook state. The method includes: (1) activating an off-hook detected signal when the telephone enters an off-hook state, (2) applying the off-hook detected signal to a selected input terminal of a coder/decoder (CODEC), (3) storing configuration information in the CODEC identifying the selected input terminal and a selected output terminal of the CODEC, (4) activating a ring cut control signal on the selected output terminal in response to the activated off-hook detected signal and the configuration information, and (5) cutting the ring current in response to the activated ring cut control signal. The CODEC includes a control register for storing the configuration information, and a hardware cut ring current (HCRC) circuit, which activates the ring cut control signal on the selected output terminal in response to the activated off-hook detected signal and the configuration information.
Abstract: CAM-based search engine devices operate to reduce the occurrence of duplicate learned entries within a CAM database when processing search and learn (SNL) instructions. A search engine device may be configured to support processing of first and second immediately consecutive and equivalent SNL instructions as a first SNL instruction and a second search and search instruction, respectively. This processing is performed in order to block an addition of a duplicate learned entry within a database in the search engine device. The search engine device may also be configured to selectively block processing of the second SNL instruction as a second search and search instruction in response to detecting the database as full when the first SNL instruction is processed.
Type:
Grant
Filed:
November 21, 2003
Date of Patent:
March 20, 2007
Assignee:
Integrated Device Technology, Inc.
Inventors:
Jakob Saxtorph, John R. Mick, Jr., Harmeet Bhugra
Abstract: An integrated circuit chip includes a search engine including a content addressable memory (CAM) configured to produce CAM indices responsive to search instructions provided to the search engine. The search engine further includes an index translation circuit operatively coupled to the CAM and configured to provide translation of the CAM indices to another memory space, such as from an absolute index space associated with the CAM to a memory space associated with a database within the CAM or to a memory space of a device external to the chip, such as a command source or external SRAM.
Type:
Grant
Filed:
December 22, 2003
Date of Patent:
February 27, 2007
Assignee:
Integrated Device Technology, Inc.
Inventors:
John R. Mick, Jr., Jakob Saxtorph, Harmeet Bhugra
Abstract: In a system having independently-clocked job-performing circuits (e.g., payload processors) and independently-clocked job-ordering circuits (e.g., request and payload suppliers), coordinating mechanisms are provided for coordinating exchanges between the independently-clocked circuits. The coordinating mechanisms include those that use transmitted time-stamps for scheduling contention-free performances within the job-performing circuits of requested jobs. The coordinating mechanisms additionally or alternatively include static and dynamic rate constraining means that are configured to prevent a faster-clocked one of the independently-clocked circuits from overwhelming a more slowly-clocked other of the independently-clocked circuits. In one implementation, independently-clocked telecommunication-shelves house a distributed set of line cards and switch cards.
Type:
Grant
Filed:
November 26, 2001
Date of Patent:
February 20, 2007
Assignee:
Integrated Device Technology, Inc.
Inventors:
Onchuen (Daryn) Lau, Matthew D. Ornes, Chris D. Bergen, Robert J. Divivier, Gene K. Chui, Christopher I. W. Norrie, King-Shing (Frank) Chui
Abstract: A method and apparatus for clock generation have been disclosed having a selector logic block that controls operation based upon inputs such as analog input(s), digital input(s), a lookup table, and preset values(s), and combinations of such.
Type:
Grant
Filed:
November 19, 2004
Date of Patent:
February 13, 2007
Assignee:
Integrated Device Technology, Inc.
Inventors:
Frank Hwang, Howard Yang, Chuen-Der Lien, Jimmy Lee
Abstract: The present invention relates to a shallow trench isolation structure and a method for forming a shallow trench isolation structure on a semiconductor substrate. A masking structure that includes a hard mask is formed over the semiconductor substrate and an etch is performed so as to form trenches within the semiconductor substrate. A shallow trench isolation structure and a method for forming a shallow trench isolation structure are disclosed. Oxidation enhancing species are then implanted into the bottom surface of the trenches and an oxidation process is performed. The oxidation enhancing species will form a deep oxidation region below the bottom surface of each trench and will form thinner oxidation regions within side surfaces of trenches. A layer of dielectric material is then deposited to fill the trenches. A chemical mechanical polishing process is performed to remove those portions of the dielectric film that overlie the hard mask.