Opinion ID: 208680
Heading Depth: 3
Heading Rank: 4

Heading: first state of circuit operation and second state of circuit operation

Text: We now reach the parties' dispute concerning the claim limitations first state of circuit operation and second state of circuit operation, which are required by claims 2, 3, 34, and 35. The Commission construed these terms to mean that the first state of operation can be linked to high load currents, and the second state can be linked to low load currents, although the states of operation do not necessarily have to be linked to a high or low load current. Final Determination, slip op. at 24. AATI contends that the first state should occur[] at high load currents, while the second state should occur[] only at low load currents. AATI argues that its construction is supported by the '258 patent's specification and by statements Linear made in prosecuting similar claims in the parent '178 patent. Linear and the Commission contend that the current constructions of these terms are correct, arguing that neither the specification of the '258 patent nor the prosecution history of the parent '178 patent clearly disavow any claim scope. We decline to disturb the Commission's constructions of first state of circuit operation and second state of circuit operation. While the '258 patent specification provides examples and embodiments where the first state of circuit operation may occur at high load currents and the second state of circuit operation may occur at low load currents, there is no clear intention to limit the claim scope using `words or expressions of manifest exclusion or restriction,' which is necessary to further narrow the claim language. Liebel-Flarsheim Co. v. Medrad, Inc., 358 F.3d 898, 906 (Fed.Cir.2004) (quoting Teleflex, Inc. v. Ficosa N. Am. Corp., 299 F.3d 1313, 1327 (Fed.Cir.2002)); see also Brookhill-Wilk 1, LLC v. Intuitive Surgical, Inc., 334 F.3d 1294, 1301 (Fed.Cir.2003) (Absent a clear disclaimer of particular subject matter, the fact that the inventor anticipated that the invention may be used in a particular manner does not limit the scope to that narrow context.). We have repeatedly held that, even in situations when only one embodiment is disclosed, the claims generally should not be narrowed to cover only the disclosed embodiments or examples in the specification. See, e.g., Liebel-Flarsheim, 358 F.3d at 906 (Even when the specification describes only a single embodiment, the claims of the patent will not be read restrictively unless the patentee has demonstrated a clear intention to limit the claim scope....); Brookhill-Wilk 1, 334 F.3d at 1301 (The statements from the description of the preferred embodiment are simply thatdescriptions of a preferred embodiment... [which] do not indicate that the invention can only be used in such a manner.). In fact, the '258 patent specification discloses situations contrary to AATI's suggested constructionoperating in the first state of circuit operation at low load currents. For example, at low load current levels when the output capacitor has fully dischargedthus being incapable of maintaining the regulated voltagethe first mode of circuit operation is initiated to vary the duty cycle of the switching transistors in order to turn the top transistor 16 ON long enough to recharge the output capacitor. See, e.g., '258 patent col.9 l.63-col.10 l.10. Nor do the statements made during prosecution of the parent '178 patent evince a `clear and unmistakable' disavowal of claim scope that would compel a result different than the claim language. ResQNet.com, Inc. v. Lansa, Inc., 346 F.3d 1374, 1383 (Fed.Cir.2003). As an initial matter, the statements made in the prosecution of the parent '178 patent do not remotely relate to the first state of circuit operation and, as such, do not narrow this limitation, as urged by AATI. See, e.g., id. (finding no clear and unmistakable disavowal of claim scope where the prosecution history of the parent patent did not address the same claim limitations); Advanced Cardiovascular Sys., Inc. v. Medtronic, Inc., 265 F.3d 1294, 1305-06 (Fed. Cir.2001) (declining to construe a term more narrowly based on the parent patent's prosecution history because common claim terms were not in dispute). Moreover, while the prosecution history of the '178 patent does mention low output current levels, it neither clearly and unmistakably addresses the second state of circuit operation nor limits that state to occurring only at low output load current. See, e.g., ResQNet.com, 346 F.3d at 1383; Advanced Cardiovascular Sys., 265 F.3d at 1305-06. Indeed, the claim amendments do not clearly and unmistakably modify the second state of circuit operation, but instead more directly address claim language not disputed in this case. In addition, the amendments do not clearly and unmistakably limit the second mode to operating at only low load currents. Rather, the amendments address when the second mode is activated specifically, when the current to the load falls lower than a predetermined threshold. In other words, the amendments specify entering the second state when the load current drops below some value in comparison to a threshold valuea value that could be relatively high or low. Thus, the amendments and statements in the parent '178 patent are plainly different than the limitations in AATI's proposed construction. In any event, the remainder of the claim language that modifies the first state and second state of circuit operations clearly describes the terms. See, e.g., Linear Tech., 379 F.3d at 1324 (looking to the other portions of the claim language in finding that further narrowing of a limitation was unnecessary). In particular, the claim language states with specificity that the first state of circuit operation corresponds to when the duty cycle of the switching transistors is varying to maintain the output at the regulated voltage. '258 patent col.16 ll.50-52. Similarly, the claim language clarifies that the second state of circuit operation corresponds to when the output capacitor maintains the output substantially at the regulated voltage. Id. col.16 ll.55-57; see id. col.2 ll.42-46; id. col.6 ll.4-8 (when the voltage at output is capable of being maintained substantially at the regulated voltage by the charge on the output capacitor). We therefore affirm the Commission's claim construction of the first state and second state of circuit operation.