PTAB

IPR2016-00995

Semiconductor Components Industries LLC doing Business As On Semiconductor v. Power Integrations Inc

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Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Switched Mode Power Supply Controller with Multi-Function Terminal
  • Brief Description: The ’908 patent relates to switched-mode power supply circuits. The disclosed technology centers on a power supply controller that uses a single "multi-function terminal" to control multiple on-chip functions, such as adjusting the current limit of a power switch, thereby reducing the required number of external pins and overall component cost.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 26-27 under 35 U.S.C. §102 by MC33362

  • Prior Art Relied Upon: Motorola MC33362 High Voltage Switching Regulator Data Sheet ("MC33362").
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that the MC33362 data sheet, published in 1997 and not considered during prosecution or reexamination of the ’908 patent, discloses every element of independent claim 26 and dependent claim 27.
      • Claim 26 (Power Supply Controller Circuit): Petitioner contended that MC33362, a monolithic power supply controller, meets all limitations of claim 26.
        • "Multi-function terminal" and "multi-function circuit": Petitioner mapped Pin 6 of the MC33362 chip to the claimed "multi-function terminal." A signal, determined by an external resistor (RT) connected to this pin, is received by MC33362's internal "Current Mirror" circuit. Petitioner asserted this "Current Mirror" is the claimed "multi-function circuit" because it performs two distinct functions based on the single input signal from Pin 6: (1) it generates a current-limit adjustment signal (with a value of "2.25 I"), and (2) it generates an oscillator frequency adjustment signal (with a value of "4 I").
        • "Current limit adjustment signal" and "control circuit": The current-limit adjustment signal generated by the "Current Mirror" is sent to MC33362's "Current Limit Comparator." Petitioner argued that this comparator, along with associated logic, constitutes the claimed "control circuit." This control circuit receives the adjustment signal and, in response, adjusts the current limit threshold for the integrated power switch, thereby satisfying the remaining limitations of claim 26.
      • Claim 27 (Control Circuit Coupling): This dependent claim adds the requirement that the control circuit is coupled to the power supply output via a control terminal and is adapted to control the switching of the power switch in response to the output. Petitioner argued MC33362 discloses this feature in at least two ways. First, the "Compensation" Pin 9 can be coupled to the power supply output (e.g., via an opto-coupler) and serves as a direct input to the PWM Comparator, controlling the power switch. Alternatively, the "Voltage Feedback Input" at Pin 10 normally connects to the converter output and provides input to an Error Amplifier, which in turn controls the PWM Comparator and power switch. Petitioner argued either configuration satisfies the limitations of claim 27.

4. Key Claim Construction Positions

  • Petitioner dedicated a significant portion of its argument to the construction of the term "multi-function circuit," which it contended is central to the anticipation analysis.
    • Proposed Construction: Petitioner argued the term should be construed as "a circuit capable of performing multiple functions."
    • Rationale: Petitioner asserted that this broad construction is supported by the ’908 patent specification, which provides a non-exclusive list of "exemplary" functions. While claim 26 explicitly requires one of the functions to be generating a current limit adjustment signal, it does not limit what the other function or functions must be. Petitioner argued this construction is necessary to encompass the specification's embodiments and allows the "Current Mirror" circuit in MC33362—which adjusts both current limit and oscillator frequency—to meet the claim limitation. This construction is critical for Petitioner’s argument that the single prior art reference anticipates the claim.

5. Relief Requested

  • Petitioner requests that the Board institute an inter partes review (IPR) and cancel claims 26 and 27 of Patent 6,538,908 as unpatentable under §102.