Patents by Inventor Anup S. Mehta

Anup S. Mehta 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: 8712752
    Abstract: In one embodiment, an IR drop analysis methodology may include characterizing standard cells without including power parasitic impedances, extracting the power parasitic impedances for the standard cells, and characterizing the standard cells with the power parasitic impedances. A set of timing parameters (such as minimum delays and maximum delays through the cells) may be generated from each characterization. The methodology may include comparing the timing parameters from each characterization, and identifying cells for which additional design effort should be expended to improve the power supply grid (e.g. to reduce the power parasitic impedances). For example, a margin may be budgeted for speed loss (delay increase) due to IR drop. If the difference in the timing parameters exceeds the margin, additional design effort may be warranted.
    Type: Grant
    Filed: February 23, 2011
    Date of Patent: April 29, 2014
    Assignee: Apple Inc.
    Inventors: Betty Y. Lau, Edgardo F. Klass, Anup S. Mehta
  • Publication number: 20120215516
    Abstract: In one embodiment, an IR drop analysis methodology may include characterizing standard cells without including power parasitic impedances, extracting the power parasitic impedances for the standard cells, and characterizing the standard cells with the power parasitic impedances. A set of timing parameters (such as minimum delays and maximum delays through the cells) may be generated from each characterization. The methodology may include comparing the timing parameters from each characterization, and identifying cells for which additional design effort should be expended to improve the power supply grid (e.g. to reduce the power parasitic impedances). For example, a margin may be budgeted for speed loss (delay increase) due to IR drop. If the difference in the timing parameters exceeds the margin, additional design effort may be warranted.
    Type: Application
    Filed: February 23, 2011
    Publication date: August 23, 2012
    Inventors: Betty Y. Lau, Edgardo F. Klass, Anup S. Mehta
  • Patent number: 7996646
    Abstract: In one embodiment, an apparatus comprises a queue comprising a plurality of entries and a control unit coupled to the queue. The control unit is configured to allocate a first queue entry to a store memory operation, and is configured to write a first even offset, a first even mask, a first odd offset, and a first odd mask corresponding to the store memory operation to the first entry. A group of contiguous memory locations are logically divided into alternately-addressed even and odd byte ranges. A given store memory operation writes at most one even byte range and one adjacent odd byte range. The first even offset identifies a first even byte range that is potentially written by the store memory operation, and the first odd offset identifies a first odd byte range that is potentially written by the store memory operation.
    Type: Grant
    Filed: March 10, 2010
    Date of Patent: August 9, 2011
    Assignee: Apple Inc.
    Inventors: Tse-yu Yeh, Daniel C. Murray, Po-Yung Chang, Anup S. Mehta
  • Publication number: 20100169619
    Abstract: In one embodiment, an apparatus comprises a queue comprising a plurality of entries and a control unit coupled to the queue. The control unit is configured to allocate a first queue entry to a store memory operation, and is configured to write a first even offset, a first even mask, a first odd offset, and a first odd mask corresponding to the store memory operation to the first entry. A group of contiguous memory locations are logically divided into alternately-addressed even and odd byte ranges. A given store memory operation writes at most one even byte range and one adjacent odd byte range. The first even offset identifies a first even byte range that is potentially written by the store memory operation, and the first odd offset identifies a first odd byte range that is potentially written by the store memory operation.
    Type: Application
    Filed: March 10, 2010
    Publication date: July 1, 2010
    Inventors: Tse-yu Yeh, Daniel C. Murray, Po Yung Chang, Anup S. Mehta
  • Patent number: 7721066
    Abstract: In one embodiment, an apparatus comprises a queue comprising a plurality of entries and a control unit coupled to the queue. The control unit is configured to allocate a first queue entry to a store memory operation, and is configured to write a first even offset, a first even mask, a first odd offset, and a first odd mask corresponding to the store memory operation to the first entry. A group of contiguous memory locations are logically divided into alternately-addressed even and odd byte ranges. A given store memory operation writes at most one even byte range and one adjacent odd byte range. The first even offset identifies a first even byte range that is potentially written by the store memory operation, and the first odd offset identifies a first odd byte range that is potentially written by the store memory operation.
    Type: Grant
    Filed: June 5, 2007
    Date of Patent: May 18, 2010
    Assignee: Apple Inc.
    Inventors: Tse-yu Yeh, Daniel C. Murray, Po-Yung Chang, Anup S. Mehta
  • Publication number: 20080307173
    Abstract: In one embodiment, an apparatus comprises a queue comprising a plurality of entries and a control unit coupled to the queue. The control unit is configured to allocate a first queue entry to a store memory operation, and is configured to write a first even offset, a first even mask, a first odd offset, and a first odd mask corresponding to the store memory operation to the first entry. A group of contiguous memory locations are logically divided into alternately-addressed even and odd byte ranges. A given store memory operation writes at most one even byte range and one adjacent odd byte range. The first even offset identifies a first even byte range that is potentially written by the store memory operation, and the first odd offset identifies a first odd byte range that is potentially written by the store memory operation.
    Type: Application
    Filed: June 5, 2007
    Publication date: December 11, 2008
    Inventors: Tse-yu Yeh, Daniel C. Murray, Po-Yung Chang, Anup S. Mehta
  • Patent number: 6981169
    Abstract: In the Retirement Payload Array (RPA) of a microprocessor, the signal “READ” is logically combined with the primary clock signal “CLK” in a control circuit of a modified glitch latch such that the glitch latch will only reset, and therefore a reset edge or “glitch” will only appear, when new data is read and the signal IN will return to zero and allow the modified glitch latch to recover.
    Type: Grant
    Filed: February 26, 2002
    Date of Patent: December 27, 2005
    Assignee: Sun Microsystems, Inc.
    Inventors: Arjun P. Chandran, Gregg K. Tsujimoto, Anup S. Mehta
  • Patent number: 6870789
    Abstract: In the Retirement Payload Array (RPA) of a microprocessor, the pointer advance signal “ADVANCE POINTER” from the Instruction Retirement Logic (IRL) of the Instruction Scheduling Unit (ISU) is utilized to provide conditional read RPA signals. Consequently, according to the invention, a read of the RPA is completed only if it is determined that the read word line being read in the current cycle is not the same read word line that was read in the previous cycle.
    Type: Grant
    Filed: February 8, 2002
    Date of Patent: March 22, 2005
    Assignee: Sun Microsystems, Inc.
    Inventors: Arjun P. Chandran, Gregg K. Tsujimoto, Anup S. Mehta
  • Publication number: 20040130350
    Abstract: A method and apparatus that dynamically control an amount of offset current generated by a keeper device are provided. Further, a method and apparatus that use a temperature-controlled keeper device to dynamically optimize an evaluation performance of a dynamic circuit are provided. In particular, when IC temperature is relatively high, i.e., there is increased current leakage in the dynamic circuit, an amount of offset current output by the temperature-controlled keeper may be increased, thereby preventing a dynamic node of the dynamic circuit from being discharged, or otherwise adversely affected, by the increased current leakage. Alternatively, when the IC temperature is relatively low, i.e., there is decreased current leakage in the dynamic circuit, the amount of offset current output by the temperature-controlled keeper may be decreased, thereby ensuring that the offset current is not so large that it severely degrades the evaluation performance.
    Type: Application
    Filed: January 7, 2003
    Publication date: July 8, 2004
    Inventors: Shaishav A. Desai, Claude R. Gauthier, Anup S. Mehta
  • Patent number: 6759877
    Abstract: A method and apparatus that dynamically control an amount of offset current generated by a keeper device are provided. Further, a method and apparatus that use a temperature-controlled keeper device to dynamically optimize an evaluation performance of a dynamic circuit are provided. In particular, when IC temperature is relatively high, i.e., there is increased current leakage in the dynamic circuit, an amount of offset current output by the temperature-controlled keeper may be increased, thereby preventing a dynamic node of the dynamic circuit from being discharged, or otherwise adversely affected, by the increased current leakage. Alternatively, when the IC temperature is relatively low, i.e., there is decreased current leakage in the dynamic circuit, the amount of offset current output by the temperature-controlled keeper may be decreased, thereby ensuring that the offset current is not so large that it severely degrades the evaluation performance.
    Type: Grant
    Filed: January 7, 2003
    Date of Patent: July 6, 2004
    Assignee: Sun Microsystems, Inc.
    Inventors: Shaishav A. Desai, Claude R. Gauthier, Anup S. Mehta
  • Patent number: 6654301
    Abstract: A bit line that has a feedback path from the bit line to a storage cell on the bit line is provided. The feedback path allows the bit line to discharge through a discharge device that is connected to a non-discharging local bit line. Further, a discharge device capable of discharging a global bit line even when a storage cell connected to the discharge device is not being evaluated is provided. Further, a method to perform a memory array operation by discharging a bit line using multiple discharge devices is provided.
    Type: Grant
    Filed: September 27, 2001
    Date of Patent: November 25, 2003
    Assignee: Sun Microsystems, Inc.
    Inventors: Farzad Chehrazi, Shaishav A. Desai, Anup S. Mehta, Devendra N. Tawari
  • Publication number: 20030163749
    Abstract: In the Retirement Payload Array (RPA) of a microprocessor, the signal “READ” is logically combined with the primary clock signal “CLK” in a control circuit of a modified glitch latch such that the glitch latch will only reset, and therefore a reset edge or “glitch” will only appear, when new data is read and the signal IN will return to zero and allow the modified glitch latch to recover.
    Type: Application
    Filed: February 26, 2002
    Publication date: August 28, 2003
    Applicant: Sun Microsystems, Inc.
    Inventors: Arjun P. Chandran, Gregg K. Tsujimoto, Anup S. Mehta
  • Publication number: 20030154365
    Abstract: In the Retirement Payload Array (RPA) of a microprocessor, the pointer advance signal “ADVANCE POINTER” from the Instruction Retirement Logic (IRL) of the Instruction Scheduling Unit (ISU) is utilized to provide conditional read RPA signals. Consequently, according to the invention, a read of the RPA is completed only if it is determined that the read word line being read in the current cycle is not the same read word line that was read in the previous cycle.
    Type: Application
    Filed: February 8, 2002
    Publication date: August 14, 2003
    Applicant: Sun Microsystems, Inc.
    Inventors: Arjun P. Chandran, Gregg K. Tsujimoto, Anup S. Mehta
  • Publication number: 20030058721
    Abstract: A bit line that has a feedback path from the bit line to a storage cell on the bit line is provided. The feedback path allows the bit line to discharge through a discharge device that is connected to a non-discharging local bit line. Further, a discharge device capable of discharging a global bit line even when a storage cell connected to the discharge device is not being evaluated is provided. Further, a method to perform a memory array operation by discharging a bit line using multiple discharge devices is provided.
    Type: Application
    Filed: September 27, 2001
    Publication date: March 27, 2003
    Inventors: Farzad Chehrazi, Shaishav A. Desai, Anup S. Mehta, Devendra N. Tawari
  • Patent number: 6466497
    Abstract: An electronic circuit has a register connected to a sense amplifier via a bitline (the sense amplifier has a primary precharge circuit), and a secondary precharge circuit also connected to the bitline. For bitlines that are relatively long, the secondary precharge circuit is located at a distal end of the bitline with respect to the sense amplifier. The secondary precharge circuit initially pulls up the voltage of the bitline, and the primary precharge circuit in the sense amplifier completes the precharging of the bitline. The secondary precharge circuit includes a cascode transistor coupled to the bitline via a feedback circuit. The feedback circuit is enabled during the precharge phase, when the bitline is discharged below a preset threshold. The threshold of the secondary precharge circuit can be set such that any skew between the precharge pulses of the secondary precharge circuit and the sense amplifier does not affect the falling bitline during the sense amplifier evaluate phase.
    Type: Grant
    Filed: April 17, 2001
    Date of Patent: October 15, 2002
    Assignee: Sun Microsystems, Inc.
    Inventors: Shaishav A. Desai, Anup S. Mehta, Srinivasa Gopaladhine
  • Patent number: 6222404
    Abstract: A shut-off circuit included in a dynamic flip-flop isolates output terminals of the dynamic flip-flop from circuitry within the flip-flop that could introduce noise on either output terminal during a portion of the evaluation phase. Since the output terminals are isolated from the input terminals during this portion of the evaluation phase, spurious input signals have no affect on the output signal levels. Similarly, charge within the dynamic flip-flop that is not completely dissipated in the transition from a precharge phase to the evaluation phase has no affect on the output signal levels during this portion of the evaluation phase.
    Type: Grant
    Filed: June 28, 1999
    Date of Patent: April 24, 2001
    Assignee: Sun Microsystems, Inc.
    Inventors: Anup S. Mehta, Chaim Amir, Edgardo F. Klass, Ashutosh K. Das
  • Patent number: 5781464
    Abstract: An incrementer for performing floating-point calculations is capable of incrementing a floating-point number represented in one of several different precision modes. The incrementer includes various incrementer portions coupled to one another and associated with the different precision modes. Circuitry is coupled to the incrementer portions to partition the floating-point number into numerous bit segments, each bit segment having an associated number. A logic circuit is coupled between a pair of said incrementer portions for controlling the incrementing of the bit segments.
    Type: Grant
    Filed: December 20, 1995
    Date of Patent: July 14, 1998
    Assignee: Intel Corporation
    Inventor: Anup S. Mehta
  • Patent number: 5345109
    Abstract: The programmable clock circuit of the present invention provides the means to generate lower frequency clock signals from a higher clock frequency signal while maintaining the synchronous relationship of the signals as well as compatible electrical characteristics of the signal. The advantages to the circuit are realized in a system in which the processor core operates at a first higher frequent clock frequency while components coupled to the processor, such as memory, operate at a lower frequency. In order to maintain electrical and timing compatibility, it is desirable to derive the lower clock frequency used to communicate with external components from the clock frequency utilized by the processor core. In the clock circuit of the present invention, the high frequency input clock signal is input to the clock circuit which has the ability to generate multiple lower frequency output signals. The actual signal output is programmable to conform to system clock requirements.
    Type: Grant
    Filed: March 30, 1993
    Date of Patent: September 6, 1994
    Assignee: Intel Corporation
    Inventor: Anup S. Mehta