PTAB

IPR2021-01460

Semiconductor Components Industries LLC v. Opticurrent LLC

Key Events

Petition

petition

Title: Three Terminal Noninverting Transistor Switch
Brief Description: The ’623 patent discloses a self-powered, three-terminal noninverting transistor switch. The technology purports to improve upon prior art by using metal-oxide semiconductor (MOS) transistors to reduce current consumption while deriving its own operating power from the voltage across its main output terminals, eliminating the need for an external power supply.

Prior Art Relied Upon: Faini (Patent 4,720,641).
Core Argument for this Ground:
- Prior Art Mapping: Petitioner argued that Faini, which discloses a self-powered switching device, teaches every limitation of claims 1-4. Faini’s “MOS power element 1” corresponds to the claimed transistor, its “CMOS pilot circuit 6” is the claimed CMOS inverter, and its “control logic circuit 9” and “charge circuit 12” collectively form the claimed voltage stabilizer. Critically, Petitioner asserted that Faini meets the preamble limitation of “having only three terminals” under the construction adopted in prior litigation. Faini derives its internal power from its output terminals and uses a capacitor (condenser 11) for energy storage, which Petitioner contended does not constitute a “fourth terminal connected to a power supply,” mirroring the Patent Owner’s successful infringement arguments in district court.
- Key Aspects: This ground heavily relies on applying the Patent Owner’s own successful claim construction arguments from prior litigation to the Faini reference, which was never considered during the patent’s examination or reexamination.

Prior Art Relied Upon: Faini (Patent 4,720,641).
Core Argument for this Ground:
- Prior Art Mapping: Petitioner presented this as an alternative argument in the event the Board adopted a stricter construction of "only three terminals" than the one used in prior litigation. Faini discloses multiple "input terminals 10" that could be used for auxiliary functions beyond the core switching operation.
- Motivation to Combine (for §103 grounds): A POSITA would combine the core features of Faini while omitting the extraneous input terminals to create a simpler, lower-cost device for applications not requiring auxiliary functions. Petitioner argued a POSITA would have recognized that only a single input terminal was necessary to achieve the fundamental self-powered switching function described, making the modification an obvious design choice driven by goals of cost and simplicity inherent in the art.
- Expectation of Success: Simplifying the input structure of Faini's circuit was a predictable modification that would not alter the core functionality of its self-powered, noninverting switch design.

Prior Art Relied Upon: Maeda (Patent 5,952,740) and Ong (Modern MOS Technology textbook, 1984).
Core Argument for this Ground:
- Prior Art Mapping: Maeda disclosed a self-powered switch that contains all the elements of the challenged claims except for the explicit use of a CMOS inverter; Maeda’s drive circuit is simply shown as “inverter Q1.” Ong was a well-known textbook that taught the advantages of implementing inverters using CMOS technology, including high speed, wide output voltage swing, and low static power dissipation.
- Motivation to Combine (for §103 grounds): A POSITA would combine Maeda with Ong’s teachings by implementing Maeda’s generic “inverter Q1” as a CMOS inverter to achieve predictable performance improvements. Specifically, the “wide output voltage swing” of a CMOS inverter (taught by Ong) would ensure Maeda’s main transistor (FET Sw1) is driven fully, minimizing resistive loss. Further, the “low-static power dissipation” of a CMOS inverter would directly further Maeda’s stated goal of enabling its power source to remain fixed for a longer time by reducing current draw.
- Expectation of Success: Implementing an inverter with CMOS technology was a standard, well-understood technique for a POSITA at the time. Applying this known technique to Maeda's circuit to improve its drive capability and power efficiency would have yielded predictable results.

"a noninverting transistor switch having only three terminals": Petitioner argued for adopting the prior District Court construction, which interpreted this phrase to mean a switch that "does not have a fourth terminal connected to a power supply." This construction allows a device to have more than three physical connections, provided it is self-powered and does not rely on an external power pin. This interpretation was central to Petitioner’s argument that Faini anticipates the claims.
"CMOS inverter interrupting the passing of current...": Petitioner proposed a construction requiring the inverter to interrupt only the current path through the inverter itself, not necessarily all possible current paths between the voltage stabilizer and the second terminal. This position was based on holding the Patent Owner to its successful infringement theory from prior litigation, where the accused products contained parallel current paths.

Petitioner argued that discretionary denial under Fintiv was improper. It asserted that the co-pending district court litigations were in early stages with no trial dates set, and that the prior art and invalidity arguments presented in the IPR were substantially different from those in the litigation, minimizing any potential for duplicative efforts.
Petitioner also contended that denial under 35 U.S.C. § 325(d) was unwarranted because the primary prior art references, Faini and Maeda, were never presented to or considered by the USPTO during either the original examination or a subsequent reexamination. Petitioner further noted that the Patent Owner was aware of these references from a parallel European prosecution but failed to disclose them during the U.S. reexamination.

Petitioner requests institution of an inter partes review and cancellation of claims 1-4 of Patent 6,958,623 as unpatentable.