DCT

1:23-cv-01246

Delta Electronics Inc v. Vicor Corp

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 1:23-cv-01246, D. Del., 01/26/2024
  • Venue Allegations: Venue is asserted on the basis that Defendant is a corporate citizen and resident of Delaware.
  • Core Dispute: Plaintiff alleges that Defendant’s power converter products infringe two U.S. patents related to over-current protection systems and high-density power supply apparatus structures.
  • Technical Context: The technology concerns advanced power converters, which are critical components for managing power delivery and efficiency in high-performance electronics such as data center servers.
  • Key Procedural History: This First Amended Complaint follows an original complaint filed on November 1, 2023. The complaint alleges Defendant had pre-suit knowledge of the ’580 Patent as early as September 28, 2018, from its citation by a USPTO examiner during the prosecution of a Vicor patent.

Case Timeline

Date Event
2010-05-28 ’580 Patent Priority Date
2014-04-29 ’580 Patent Issue Date
2014-09-02 ’534 Patent Priority Date
2018-09-28 ’580 Patent cited in prosecution of Vicor patent application
2020-12-29 ’534 Patent Issue Date
2023-07-12 Date before which Vicor allegedly investigated Delta patents
2023-11-01 Plaintiff's Original Complaint Filing Date
2024-01-26 Plaintiff's First Amended Complaint Filing Date

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 8,711,580 - “Resonant Conversion System with Over-Current Protection Processes,” issued April 29, 2014

The Invention Explained

  • Problem Addressed: The patent’s background section describes the challenge of providing effective over-current protection (OCP) for resonant converters, which can experience damagingly large current surges during overload, short-circuit, or startup conditions (’580 Patent, col. 1:26-44). Conventional protection methods are noted to have defects, such as increased power consumption or restrictive circuit design requirements (Compl. ¶21; ’580 Patent, col. 1:45-51, col. 2:1-15).
  • The Patented Solution: The invention proposes a two-stage conversion system. A first-stage buck converter provides a controlled DC voltage to a second-stage resonant converter. The controller can command the buck converter to decrease its output voltage (which is the input voltage for the resonant converter) when an over-current condition is detected, thereby protecting the system from damage (’580 Patent, Abstract; col. 2:19-34). Figure 3 illustrates this two-stage architecture (’580 Patent, Fig. 3).
  • Technical Importance: This architecture provides a method for robust over-current protection that aims to avoid the efficiency losses and design limitations associated with prior art solutions, enabling the use of high-efficiency resonant converters in demanding applications (’580 Patent, col. 1:18-24).

Key Claims at a Glance

  • The complaint asserts infringement of "at least one claim" without specifying which ones (Compl. ¶52). Independent claim 1 is representative.
  • Essential elements of Independent Claim 1:
    • A resonant converter for receiving an input voltage and generating an output voltage.
    • A buck converter for providing and controlling the input voltage for the resonant converter to perform an over-current protection process.
    • A first controller that decreases the duty cycle of the buck converter to lower the input voltage to the resonant converter when an over-current is generated.
  • The complaint does not explicitly reserve the right to assert dependent claims.

U.S. Patent No. 10,877,534 - “Power Supply Apparatus,” issued December 29, 2020

The Invention Explained

  • Problem Addressed: The patent addresses the need for power supplies with higher power density and efficiency, particularly for space-constrained applications like modern servers. Traditional power supplies built on a single printed circuit board (PCB) are limited in how compactly their components can be arranged, which restricts power density and can complicate thermal management (’534 Patent, col. 1:22-48).
  • The Patented Solution: The invention discloses a power supply apparatus with a vertically stacked structure. A "power unit" and a "control unit" are stacked on top of one another on a main board to make better use of the vertical height available within a server chassis (’534 Patent, col. 4:9-16). This structure is designed to increase "power pressure" (power per unit of horizontal area) (’534 Patent, col. 2:1-12). Electrical interconnections between the stacked modules are made using a plurality of pins, which are "allocated along lateral sides of the insulation material" that encapsulates the components (’534 Patent, Abstract; col. 3:1-4).
  • Technical Importance: This stacked design directly addresses the industry demand for increased power density, allowing more powerful and efficient converters to fit within standardized, compact server form factors (’534 Patent, col. 1:36-43).

Key Claims at a Glance

  • The complaint asserts infringement of "at least one claim" without specification (Compl. ¶62). Independent claim 1 is representative.
  • Essential elements of Independent Claim 1:
    • A bearing plate.
    • Insulation material formed on two opposite surfaces of the bearing plate.
    • A plurality of pins electrically connected to the bearing plate.
    • The pins are allocated along lateral sides of the insulation material.
    • Terminals of each pin have two SMD pads extending to an upper and lower surface of the insulation material.
  • The complaint does not explicitly reserve the right to assert dependent claims.

III. The Accused Instrumentality

  • Product Identification: The complaint identifies the "Vicor Accused Products" as a line of power converters, providing specific, non-limiting examples: the Vicor VTM 48EF060T040A00 and PRM48AF480T400A00 power converters (accused of infringing the ’580 Patent) and the Vicor NBM 2317S60E1560T0R power converter (accused of infringing the ’534 Patent) (Compl. ¶¶24, 45, 46).
  • Functionality and Market Context: The accused products are power converters designed for applications such as power supplies for servers (Compl. ¶24). Plaintiff alleges that Defendant Vicor is a direct competitor and that the accused products are sold in the U.S. through a direct sales force, a website, and a network of electronics distributors (Compl. ¶¶3, 28, 29).

IV. Analysis of Infringement Allegations

The complaint alleges infringement but incorporates by reference external Exhibits 3 and 4, which are claim charts that were not provided. The narrative infringement theory is summarized below.

  • ’580 Patent Infringement Allegations: The complaint alleges that Vicor’s VTM and PRM power converters directly infringe at least one claim of the ’580 Patent (Compl. ¶¶45, 52). The stated theory is that these products contain an "improved design for a resonant converter system that includes protection from excessively high current" (Compl. ¶21). The specific mechanism by which the accused products are alleged to meet the claim limitations of a two-stage buck converter/resonant converter system is detailed in the un-provided Exhibit 3 (Compl. ¶25). No probative visual evidence provided in complaint.
  • ’534 Patent Infringement Allegations: The complaint alleges that Vicor’s NBM power converter directly infringes at least one claim of the ’534 Patent (Compl. ¶¶46, 62). The narrative theory is that the accused product embodies an "improved design for a power supply that results in more efficient and economical power transmission," which aligns with the patent's focus on high-density, stacked architectures (Compl. ¶22). The element-by-element mapping of the accused product's structure to the patent's claims is contained within the un-provided Exhibit 4 (Compl. ¶26). No probative visual evidence provided in complaint.
  • Identified Points of Contention:
    • For the ’580 Patent: A central technical question will be whether the accused products implement the specific two-stage architecture recited in the claims. The dispute may focus on whether a circuit within the accused products qualifies as a "buck converter" that "controls the input voltage" of a "resonant converter" for the purpose of over-current protection, or if it achieves protection through a different, non-infringing mechanism.
    • For the ’534 Patent: The infringement analysis will likely turn on questions of structural correspondence. A key issue will be whether the physical construction of the accused NBM converter meets the claim limitations of a "stacked" apparatus with pins "allocated along lateral sides" for interconnection, raising questions about the precise meaning and scope of these structural terms.

V. Key Claim Terms for Construction

  • From the ’580 Patent (Claim 1):
    • The Term: "a buck converter"
    • Context and Importance: This term is foundational to the claimed two-stage system. The infringement analysis will depend on whether a component within Vicor's products constitutes a "buck converter" as understood in the context of the patent. Practitioners may focus on this term because Defendant could argue its voltage regulation circuitry is not a "buck converter" or operates in a materially different way.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The specification describes the function of the buck converter as adjusting an input voltage V1 to a voltage V2 to serve as the input for the resonant converter, which could support a functional definition not tied to a specific topology (’580 Patent, col. 3:40-49).
      • Evidence for a Narrower Interpretation: The patent provides a specific exemplary circuit diagram for the buck converter in Figure 8, including switch SW1, diode D1, and inductor L1. This embodiment could be used to argue for a narrower construction limited to the disclosed topology or its structural equivalents (’580 Patent, Fig. 8).
  • From the ’534 Patent (Claim 1):
    • The Term: "allocated along lateral sides of the insulation material"
    • Context and Importance: This phrase defines the physical location of the electrical pins that connect the stacked modules, a key structural feature of the invention. The outcome of the infringement analysis may depend on whether the accused product's pin layout falls within the scope of this term.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: Figure 22 depicts an embodiment where pins are distributed along three of the four sides of the apparatus, which may support a construction that does not require pins to be on all lateral sides, or to be exclusively on the lateral sides (’534 Patent, Fig. 22).
      • Evidence for a Narrower Interpretation: The abstract states pins are "allocated along lateral sides," and Figure 21 shows a distinct arrangement with pins only on two opposite parallel sides. This could support an argument that the term requires a more limited configuration than that alleged to be found in the accused product (’534 Patent, Abstract; Fig. 21).

VI. Other Allegations

  • Indirect Infringement: The complaint alleges both induced and contributory infringement. The inducement allegations are based on Vicor’s provision of datasheets, marketing materials, and technical support that allegedly instruct and encourage customers to use the accused converters in an infringing manner (Compl. ¶¶37, 55). The contributory infringement allegations state that the accused products are a material part of the invention and lack substantial non-infringing uses (Compl. ¶¶56, 66).
  • Willful Infringement: Willfulness is alleged based on both pre- and post-suit knowledge. The complaint asserts pre-suit knowledge stemming from Vicor’s status as a competitor, its alleged IP review practices, and, for the ’580 Patent, a citation by the USPTO against a Vicor patent application on September 28, 2018 (Compl. ¶¶38, 42). Post-suit knowledge is alleged from the date of the original complaint, November 1, 2023 (Compl. ¶40).

VII. Analyst’s Conclusion: Key Questions for the Case

  • A core issue for the ’534 Patent will be one of structural scope: can the claim terms defining the physical architecture, such as "stacked" units and pins "allocated along lateral sides," be construed to read on the specific construction of the accused Vicor NBM converter, or is there a fundamental mismatch in their design?
  • A key evidentiary question for the ’580 Patent will be one of functional equivalence: do the accused Vicor converters employ a front-end circuit that operates as a "buck converter" to control the input voltage of a back-end "resonant converter" for over-current protection, as required by the claims, or do they achieve a similar result through a materially different technical approach?
  • A central procedural question will be the sufficiency of the pleadings: given the complaint's reliance on incorporating external, un-provided claim charts by reference, does the complaint itself allege sufficient factual matter to state a plausible claim for infringement for each patent, or will it be vulnerable to a motion to dismiss for failure to meet the Iqbal/Twombly pleading standard?