PTAB

IPR2016-01266

Texas Instruments Inc v. Advanced Silicon Technologies LLC

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Method and System for Increasing the Ability of Memory Controllers to Intelligently Schedule Accesses to System Memory
  • Brief Description: The ’439 patent relates to a system for improving memory access efficiency by providing a memory controller with additional information about each memory request. The key inventive concept is the use of a "source indication" and other parameters, passed from a memory operation buffer to the controller, to enable more intelligent scheduling.

3. Grounds for Unpatentability

Ground I: Claims 1, 4, 7, 10, and 15 are obvious over Pattin

  • Prior Art Relied Upon: Pattin (Patent 5,745,913).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Pattin, which describes a memory controller that re-orders requests from multiple sources (CPUs, PCI bus) to optimize bandwidth, discloses all limitations of claim 1. Pattin’s “request queue” was mapped to the claimed “memory operation buffer,” and its “request prioritizer” was mapped to the “memory controller.” Crucially, Pattin disclosed that each memory request includes a “source field” that stores an “identifier for the source of the request,” directly teaching the claimed “source indication.” For dependent claims, Pattin’s disclosure of other fields like a “ROW_HIT” bit was argued to meet the limitation of “one or more parameters” (claim 4), a “speculative/demand bit” met the parameter for speculative requests (claim 7), and the request fields collectively constituted a “tag” (claim 10).
    • Motivation to Combine (for §103 grounds): Not applicable (single reference ground).
    • Expectation of Success (for §103 grounds): Not applicable (single reference ground).

Ground VI: Claims 1, 2, and 14 are obvious over Nielsen

  • Prior Art Relied Upon: Nielsen (Patent 6,104,417).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted that Nielsen provided an alternative, but equally obvious, path to the claimed invention, corresponding to the ’439 patent’s separate-queue embodiment. Nielsen disclosed a computer system with multiple “memory system clients” (e.g., CPU, rendering engine) that place requests into separate “client queues” before being handled by a memory controller’s arbiter. Petitioner mapped these separate client queues to the claimed “requested memory operation buffer.” The source indication was argued to be inherently provided because the arbiter knows the source of a request by identifying the specific queue from which it was received. For dependent claims, Petitioner argued Nielsen’s arbiter groups requests by servicing a given client queue for an “arbitration slot” (claim 2) and that the system of distinct queues for each source directly taught the limitations of claim 14.
    • Motivation to Combine (for §103 grounds): Not applicable (single reference ground).
    • Expectation of Success (for §103 grounds): Not applicable (single reference ground).

Ground VII: Claims 3-5 are obvious over the combination of Nielsen and Pattin

  • Prior Art Relied Upon: Nielsen (Patent 6,104,417) and Pattin (Patent 5,745,913).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground built upon Nielsen by adding Pattin’s more advanced scheduling techniques. Petitioner argued that while Nielsen taught grouping requests by source (in separate queues), it lacked an explicit teaching of reordering requests within that group to prioritize those hitting an already open memory page. Pattin was cited for expressly teaching this technique using a “ROW_HIT” parameter. The combination was alleged to render claim 3 obvious. Similarly, Pattin’s use of multiple parameter fields (source ID, ROW_HIT, etc.) was argued to supplement Nielsen’s system to meet the limitations of providing additional parameters (claim 4) and an identity of the request initiator (claim 5).
    • Motivation to Combine (for §103 grounds): A POSITA would combine the teachings of Pattin with the system of Nielsen to enhance scheduling performance. Starting with Nielsen's efficient source-based grouping via separate queues, a POSITA would incorporate Pattin's known technique of prioritizing open-page requests to further optimize memory bandwidth and avoid wasting time closing and opening memory pages unnecessarily.
    • Expectation of Success (for §103 grounds): The combination involved applying a known optimization technique (Pattin's open-page prioritization) to a known system architecture (Nielsen's multi-queue system), which would have yielded the predictable result of improved memory access efficiency.

  • Additional Grounds: Petitioner asserted additional obviousness challenges, including combinations of Pattin with Talbot (Patent 6,272,600) for adding a priority parameter (claim 6); Pattin with Nguyen (Patent 6,163,818) or Wulf (Patent 6,154,826) for adding a stream/thread identity parameter (claim 8); Pattin with Hacking (Patent 5,946,713) for adding an out-of-order completion parameter (claim 9); and combinations of Nielsen with Nguyen or Wulf for adding a stream/thread identity parameter (claim 16).

4. Key Claim Construction Positions

  • "source indication" (claim 1): Petitioner proposed this term be construed as "information that can be used to determine the source of the request." This construction was argued to be broad enough to encompass both embodiments in the ’439 patent: (i) specific identifying information in a data field (as in the patent's Figure 3 embodiment and taught by Pattin) and (ii) the use of separate queues where the queue’s identity itself serves as the source information (as in the patent’s Figure 5 embodiment and taught by Nielsen).
  • "tag" (claim 10): Petitioner proposed this term be construed as "a data structure that includes information." This construction was based on the patent’s disclosure that a tag may contain one or more parameters related to a transaction, which a POSITA would understand requires a data structure for storage.

5. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-10 and 14-16 of the ’439 patent as unpatentable.