LED Apogee LLC v. Analog Devices Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: LED Apogee LLC (Delaware)
  • Defendant: Analog Devices, Inc. (Massachusetts)
  • Plaintiff’s Counsel: Rabicoff Law LLC
• Case Identification: 2:24-cv-00019, E.D. Tex., 01/12/2024
• Venue Allegations: Plaintiff alleges venue is proper because Defendant maintains an established place of business in the Eastern District of Texas.
• Core Dispute: Plaintiff alleges that certain of Defendant’s products infringe a patent related to methods for driving light-emitting diodes (LEDs).
• Technical Context: The lawsuit concerns electronic circuits that provide power to LEDs, a technology fundamental to modern lighting, displays, and consumer electronics.
• Key Procedural History: The complaint does not mention any prior litigation, inter partes review (IPR) proceedings, or licensing history related to the patent-in-suit.

Case Timeline

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

U.S. Patent No. 6,982,527 - "Method for driving light emitting diode"

• Patent Identification: U.S. Patent No. 6,982,527, "Method for driving light emitting diode", issued January 3, 2006.

The Invention Explained

• Problem Addressed: The patent describes a problem in prior art LED driver circuits where significant power is wasted. Specifically, when a current mirror circuit drives an LED, there is often a large and inefficient voltage drop across the mirror, leading to excess power loss, particularly when driving white LEDs whose voltage requirements can vary. ('527 Patent, col. 1:37-49).
• The Patented Solution: The invention proposes a method to improve efficiency by using the input of the LED itself as a "voltage feedback point." This feedback is used to regulate the voltage supplied to the current mirror, specifically to maintain a constant voltage difference between the current mirror's input and output. By keeping this difference small and constant, the method aims to minimize the power loss described by the equation PLEDLOSS=ILED(VOUT-VF). ('527 Patent, Abstract; col. 4:5-18).
• Technical Importance: This approach seeks to overcome the low efficiency of conventional charge pumps and reduce power loss, which is critical for extending battery life in portable electronics and managing heat in solid-state lighting systems. ('527 Patent, col. 1:52-60).

Key Claims at a Glance

• The complaint does not specify which claims are asserted in its narrative text, instead referring to "Exemplary '527 Patent Claims" in an incorporated but unattached exhibit (Compl. ¶11). Independent claim 1, as the broadest method claim, is a likely candidate for assertion.
• Essential elements of independent claim 1 include:
  • providing a control terminal voltage of said current mirror as a reference voltage;
  • increasing a voltage of an input of said current mirror and providing an input of said light emitting diode as a voltage feedback point for keeping a constant voltage difference between said input and said output of said current mirror; and
  • driving said light emitting diode by a voltage at said output of said current mirror.
• The complaint does not explicitly reserve the right to assert dependent claims.

III. The Accused Instrumentality

Product Identification

• The complaint does not identify any specific accused products by name in its body. It refers to "Exemplary Defendant Products" that are purportedly identified in charts within "Exhibit 2" (Compl. ¶11, ¶16). This exhibit was not filed with the public version of the complaint.

Functionality and Market Context

• The complaint alleges that the accused products are made, used, sold, or imported by Defendant and that they "practice the technology claimed by the '527 Patent" (Compl. ¶11, ¶16). No specific details regarding the functionality, operation, or market context of the accused products are provided in the complaint itself.

IV. Analysis of Infringement Allegations

The complaint alleges that "Exhibit 2", which was not provided, contains charts comparing the asserted claims to the accused products (Compl. ¶16-17). Without this exhibit, the complaint's narrative states only that the accused products "satisfy all elements of the Exemplary '527 Patent Claims" (Compl. ¶16). The complaint does not provide sufficient detail for analysis of how any specific product feature is alleged to meet any specific claim limitation.

No probative visual evidence provided in complaint.

• Identified Points of Contention: Based on the patent and the general nature of the allegations, the infringement analysis may raise several questions:
  • Evidentiary Question: What evidence will be presented to demonstrate that the accused products, once identified, actually perform the step of "providing an input of said light emitting diode as a voltage feedback point" as required by the claim?
  • Technical Question: Do the accused products' circuits operate to maintain a "constant voltage difference" between the input and output of a current mirror, or do they achieve voltage regulation through a technically distinct mechanism?
  • Scope Question: How broadly will the term "current mirror" be interpreted, and do the accused circuits contain a structure that meets that definition as understood in the context of the patent?

V. Key Claim Terms for Construction

• The Term: "voltage feedback point"
• Context and Importance: This term appears to be central to the novelty of the invention, as it describes the mechanism for overcoming the power loss problems of the prior art. The infringement case will likely depend on whether the accused products utilize a circuit node that can be properly characterized as a "voltage feedback point" for the specific purpose recited in the claim.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The claim language recites "providing an input of said light emitting diode as a voltage feedback point," which could be argued to encompass any circuit architecture that senses a voltage at or near the LED's input to control the power-supply voltage. ('527 Patent, col. 5:12-14).
  • Evidence for a Narrower Interpretation: The specification discloses specific embodiments where the feedback point is a particular node (e.g., node A42 in FIG. 4) used to regulate an "inductive charge pumping circuit" to maintain the constant voltage difference. ('527 Patent, col. 4:5-18). A party could argue the term should be limited to such a structure and function, which is explicitly presented as the solution to the power loss problem. ('527 Patent, col. 4:32-37).

VI. Other Allegations

• Indirect Infringement: The complaint alleges induced infringement, asserting that Defendant distributes "product literature and website materials" that direct end users to use the accused products in a manner that infringes the ’527 Patent (Compl. ¶14).
• Willful Infringement: The complaint alleges that Defendant has had "actual knowledge of infringement" since the service of the complaint and associated claim charts (Compl. ¶13). The allegations of continued infringement after this notice form the basis for a claim of post-filing willfulness (Compl. ¶15).

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

Given the limited factual detail in the complaint, the initial phases of the case will likely focus on establishing a basic factual record. The central questions that emerge are:

1. An Evidentiary Question of Operation: Once the accused products are identified, the key question will be whether discovery reveals that they technically operate in the manner claimed. Specifically, does their circuitry use a feedback mechanism originating from the LED input to actively maintain a constant voltage differential across a current mirror, or do they employ a different power regulation scheme?
2. A Definitional Question of Scope: The dispute will likely involve a debate over the meaning of key claim terms. A core issue will be one of claim construction: can the term "voltage feedback point," as described in the patent, be construed to read on the specific circuit architecture and functionality of the accused products?