Ex Parte Knoblinger et alDownload PDFPatent Trial and Appeal BoardDec 10, 201412543629 (P.T.A.B. Dec. 10, 2014) Copy Citation UNITED STATES PATENT AND TRADEMARK OFFICE ________________ BEFORE THE PATENT TRIAL AND APPEAL BOARD ________________ Ex parte GERHARD KNOBLINGER,1, 2 Marc Tiebout, and Franz Kuttner ________________ Appeal 2013-001061 Application 12/543,629 Technology Center 2800 ________________ Before JEFFREY T. SMITH, BEVERLY A. FRANKLIN, and MARK NAGUMO, Administrative Patent Judges. NAGUMO, Administrative Patent Judge. DECISION ON APPEAL Gerhard Knoblinger, Marc Tiebout, and Franz Kuttner (“Infineon”) timely appeal under 35 U.S.C. § 134(a) from the Final Rejection3 of claims 1–12, which are all of the pending claims. We have jurisdiction. 35 U.S.C. § 6. We affirm. 1 The real party in interest is listed as Infineon Technologies AG (“Infineon”). (Appeal Brief, filed 11 June 2012 (“Br.”), 3.) 2 Appeal 2013-009183 in co-pending application 12/543,637, which was filed on the same date as this application, and which shares a substantially identical specification, is decided concurrently. 3 Office action mailed 26 September 2011. Appeal 2013-001061 Application 12/543,629 2 OPINION A. Introduction4 The subject matter on appeal relates to voltage controlled oscillators (“VCO”) having drain extended MOS (“DeMOS”) transistors as active devices. Such DCOs are said to have significantly improved phase noise compared to prior art DCOs. (Spec. 4 [0014].) An embodiment of the invention is illustrated in Figure 1, infra. {Fig. 1 shows a circuit diagram of a VCO of the invention} 4 Application 12/543,629, DeMOS VCO, filed 19 August 2009. We refer to the “ʼ629 Specification,” which we cite as “Spec.” Appeal 2013-001061 Application 12/543,629 3 VCO 1005 comprises an LC tank circuit 102, a cross coupled pair circuit 104, and bias circuit 106 (Spec. 2 [0008]), which produces a differential oscillating signal produced between output terminals OUTn and OUTp (id. at 2 [0009]). LC tank circuit 102 is coupled to supply voltage Vdd, and comprises inductors 108 and 110 and variable capacitors (“varactors”) 112 and 114, which may be implemented using diodes or MOS capacitors. (Id.) Cross- coupled circuit 104 comprises drain-extended MOS transistors (“DeMOS”) 116 and 118, the gate of one being coupled to the drain of the other via AC-coupling capacitors 120 and 122. (Id. at 3 [0010].) AC-coupling capacitors 120 and 122 are said to help prevent a high voltage that may be present on the respective drains of DeMOS transistors 116 and 118 from affecting the gates of transistors 118 and 116, respectively. (Id. at 4 [0013].) The presence of the DeMOS transistors is said to “allow for a greater voltage swing on the drain as compared to the voltage swing on the gate,” which in turn is said to improve significantly the phase noise characteristics of the output. (Id. at [0014].) Claim 1 is representative of the dispositive issues and reads: A circuit arrangement, comprising: a voltage controlled oscillator (VCO) circuit having at least two active devices, wherein the at least two active devices are drain extended (DeMOS) MOS transistors; and an LC tank coupled to the DeMOS transistors, the LC tank including 5 Throughout this Opinion, for clarity, labels in Figures are presented in bold font, regardless of their presentation in the original document. Appeal 2013-001061 Application 12/543,629 4 a first varactor coupled to a first DeMOS transistor of the DeMOS transistors and a second varactor coupled to a second DeMOS transistor of the DeMOS transistors. (Claims App., Br. 11; some indentation, paragraphing, and emphasis added.) Claim 9, the other independent claim, is similar, but further requires that a bias circuit be coupled to the DeMOS transistors. (Id. at 12.) The Examiner maintains the following ground of rejection:6,7 Claims 1–12 stand rejected under 35 U.S.C. § 103(a) in view of the combined teachings of Amano,8 Schneider,9 and Gabara.10 B. Discussion Findings of fact throughout this Opinion are supported by a preponderance of the evidence of record. Initially, we find that Infineon presents arguments for the patentability based on the requirement, common to both independent claims 1 and 9, that 6 Examiner’s Answer mailed 16 August 2012 (“Ans.”). 7 An obviousness-type double patenting rejecting in view of copending application 12/543,637 has been withdrawn in view of the terminal disclaimer filed with the Brief (Br. 5). (Ans. 3.) 8 Shinji Amano, Voltage control oscillator . . . , U.S. Patent Application Publication 2007/0075798 A1 (2007). 9 Jens Schneider and Harald Gossner, Drain-extended field effect transistor, U.S. Patent Application Publication 2009/0140335 A1 (4 June 2009), based on an application filed 4 December 2007: now U.S. Patent No. 7,838,940, assigned to Infineon Technologies AG. 10 Thaddeus Gabara and Vladimir Prodanov, Low-power-dissipation CMOS oscillator circuits with capacitively coupled frequency control, U.S. Patent No. 7,274,264 B2 (2007). App App the c there oscil DeM that elect DeM (The emb cons eal 2013-0 lication 12 ircuit com fore stand Briefly, lator circu OS transi Schneider rostatic di OS transi Examiner odiments w ider Gabar 01061 /543,629 prise drain or fall wit the Exami it within th stors as the describes scharge, an stors in pla relies on ithin the a further.) {Ama {Amano extended h claim 1. ner finds t e scope o cross-cou DeMOS tr d reasons ce of the t Gabara as scope of d no Figure Figure 1 i 5 (DeMOS) hat Amano f the appea pled trans ansistors a that it wo ransistors evidence o ependent c 1 is reprod llustrates MOS tran describes led claim istor pair. s being re uld have b described f the obvi laim 3, so uced belo a VCO cir sistors. A a voltage s, but for t The Exam sistant to een obvio by Amano ousness of we need n w} cuit} ll claims controlled he use of iner finds us to use . ot Appeal 2013-001061 Application 12/543,629 6 VCO 1a comprises resonance circuit 2, which in turn comprises inductors 3 and variable capacitors 4 and 5. (Amano 3 [0033]–[0035].) Transistors 9 amplify an oscillation signal that is generated by resonance circuit 2. (Id. at [0040].) Capacitors 15 isolate bases 11 from DC voltage 12 at the collectors 10, while coupling the AC signal. (Id.) A bias voltage is supplied to the base 11 from bias circuit 16. (Id.) Infineon does not dispute the Examiner’s findings that all the limitations required by claims 1 and 9, but for the DeMOS transistors, are described by Amano. In Infineon’s view, however, Amano fails to suggest the use of transistors other than NMOS and PMOS transistors (Br., para. bridging 6–7.) Moreover, Infineon argues, the Examiner has failed to provide a convincing line of reasoning why it would have been an obvious matter of design choice, or why it would have been obvious to try using DeMOS transistors in Amano’s VCO circuit. (Id. at 8, 1st full para.) These arguments are not persuasive of harmful error. In light of Amano’s teachings, the circuit designer would have expected, reasonably, that any type of transistor having appropriate characteristics would have been suitable for use in the VCO described by Amano. Cf. In re O'Farrell, 853 F.2d 894, 904 (Fed. Cir. 1988) (“For obviousness under §103, all that is required is a reasonable expectation of success.”). The substitution of an equivalent functional component for another is a classic instance of an obvious substitution. Infineon has not directed our attention to any credible evidence of record that DeMOS transistors were recognized as having characteristics that would have dissuaded the routineer from using them in place of the more conventional transistors named by Amano. Appeal 2013-001061 Application 12/543,629 7 Infineon’s arguments that the claims are patentable due to the unexpected ability of the DeMOS transistors to provide a “greater voltage swing on the drain [that] significantly improves phase noise” (Br. 8, ll. 20-21) are not persuasive due to the lack of supporting evidence in the record. The ʼ629 Specification lacks any working examples, and the Brief and Reply11 are also devoid of examples and comparisons with the prior art. In re De Blauwe, 736 F.2d 699, 705 (Fed. Cir. 1984) (“[i]t is well settled that unexpected results must be established by factual evidence. Mere argument or conclusory statements in the specification does not suffice.”) In this regard, we note that Amano discloses that phase noise is kept low by keeping the VCO Kv gain low (Amano 4 [0046]). It is clear that there is considerable complexity within the scope of the seemingly simple VCO circuits covered by the appealed claims. Thus, Infineon’s arguments for patentability based on unexpected results are also not reasonably commensurate with the scope of exclusionary rights sought. In re Harris, 409 F.3d 1339, 1344 (Fed. Cir. 2005) (evidence of secondary considerations must be “commensurate in scope with the degree of protection sought by the claimed subject matter.”) C. Order We affirm the rejection of claims 1–12. No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a). AFFIRMED 11 Reply Brief filed 16 October 2012 (“Reply”). 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