Ex Parte Dargelas et al

Board of Patent Appeals and Interferences

Sep 11, 2009

10906571 (B.P.A.I. Sep. 11, 2009)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte ALAIN DARGELAS, PARAS MAL JAIN, ASHISH HARI,
BERNARD MURPHY, and ANTHONY JOSEPH
_____________

Appeal 2009-002379
Application 10/906,571
Technology Center 2800
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Decided: September 11, 2009
____________

Before JOHN A. JEFFERY, THOMAS S. HAHN,
and ELENI MANTIS MERCADER, Administrative Patent Judges.

MANTIS MERCADER, Administrative Patent Judge.

DECISION ON APPEAL

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STATEMENT OF THE CASE
Appellants seek our review under 35 U.S.C. § 134(a) of the Examiner’s final
rejection of claims 1-24. We have jurisdiction under 35 U.S.C. § 6(b).
We affirm.

INVENTION
Appellants’ claimed invention is directed to recognizing handshake data
exchange at clock-domain crossings by performing a particular structural analysis
of integrated circuit designs (Spec. 7: ¶ [23]).
Claim 1, reproduced below, is representative of the subject matter on appeal:
1. A method for the automatic recognizing of a handshake
data exchange at a clock-domain crossing, comprising:
performing a structural analysis of an integrated circuit (IC) design
comprising:
determining one or more clock-domain crossings in an integrated circuit (IC)
design;
for each enabled source register and enabled destination register in each of
the determined clock-domain crossings, recognizing a handshake data exchange
by:
detecting a source final state machine (FSM) connected to the source
enabled register;
detecting a destination FSM connected to the destination enabled register;
detecting at least one request signal driven by the source FSM; and
detecting at least one acknowledge signal driven by the destination FSM.

THE REJECTIONS
The Examiner relies upon the following as evidence of unpatentability:
Rohrbaugh US 2004/0044972 A1 Mar. 4, 2004

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Sarwary US 2005/0097484 A1 May 5, 2005
(filed Oct. 30, 2003)

Suaris US 2005/0132316 A1

Jun. 16, 2005
(filed Mar. 18, 2004)

The following rejections are before us for review:
1. The Examiner rejected claims 1-7, 9-19, and 21-24 under 35 U.S.C.
§ 102(e) as being anticipated by Sarwary.
2. The Examiner rejected claims 8 and 20 under 35 U.S.C. § 103(a) as being
unpatentable over Sarwary in view of Rohrbaugh and/or Suaris.
Appellants argue the anticipation rejection of claims 1, 3-7, 9-13, 15-19, and
21-24 as a group and limit their arguments pertaining to this rejection with respect
to independent claims 1 and 13 (App. Br. 11-20).1 Accordingly, we select claim 1
as representative of this group. Therefore, claims 3-7, 9-13, 15-19, and 21-24
stand or fall with claim 1. See 37 C.F.R. § 41.37 (c)(1)(vii) (2004). Appellants
argue claims 2 and 14 separately.
We acknowledge that Appellants, at pages 8-9 of the Reply Brief, have
made separate arguments for the availability of Sarwary as a prior art reference
under 35 U.S.C. § 103(c). This issue, however, was raised for the first time on
appeal in the Reply Brief and is therefore deemed to be waived. See Optivus
Tech., Inc. v. Ion Beam Appl’ns S.A., 469 F.3d 978, 989 (Fed. Cir. 2006) (“[A]n

1 Only arguments made by Appellants have been considered in this decision.
Arguments which Appellants could have made but did not make in the Briefs have
not been considered and are deemed waived. See 37 C.F.R. § 41.37(c)(1)(vii)
(2004).
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issue not raised by an appellant in its opening brief . . . is waived.”) (citations and
quotation marks omitted); see also Ex parte Scholl, No. 2007-3653, slip op. at n.13
(BPAI Mar. 13, 2008) (informative), available at
http://www.uspto.gov/web/offices/dcom/bpai/its/fd073653.pdf (same).

ANTICIPATION
ISSUES
Regarding the rejection of claims 1, 3-7, 9-13, 15-19, and 21-24
Appellants argue that Sarwary is not directed to the same purpose as the
present invention (App. Br. 11). Appellants assert that checking if a structural
synchronization cell exists in the design is not equivalent to the performing of
structural analysis (App. Br. 11). According to Appellants, the method disclosed
in the present application and described in the claims is capable of recognizing
handshake data exchange by performing structural analysis of the circuit inspected
(App. Br. 12). Appellants assert that it is well known in the art that structural
analysis is the verification of an IC design by exploring the structure of the design
(App. Br. 12). Appellants further state that this is typically done by identifying
synchronization cells in the design, such as double register level and a recirculation
MUX (App. Br. 12).
Appellants further argue that Sarwary does not include (1) performing a
structural analysis of an integrated circuit (IC) design; (2) detecting at least one
request signal driven by the source FSM; and (3) detecting at least one
acknowledge signal driven by the destination FSM as claimed (App. Br. 13-14).
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Appellants argue that Sarwary teaches a method aimed at validating a clock-
domain crossing that does not include a handshake mechanism (App. Br. 17).
Appellants assert that the present application performs structure analysis to prove
that a data structure at a clock-domain crossing is indeed a handshake mechanism
(App. Br. 17). Appellants explain that this requires a “request signal” and an
“acknowledge signal” (emphasis in original) (App. Br. 17-18).
The first issue, then, is whether Appellants have shown that the Examiner
erred in finding that Sarwary teaches (1) recognizing of a handshake data exchange
at a clock-domain crossing as recited in the preamble of claims 1 and 13; and also
(2) performing a structural analysis of an integrated circuit (IC) design; (3)
detecting at least one request signal driven by the source FSM; and (4) detecting at
least one acknowledge signal driven by the destination FSM as recited in the body
of claims 1 and 13.
Regarding the rejection of claims 2 and 14
Appellants argue that Sarwary does not teach generating a report indicating a
handshake data exchange being identified in the IC design (App. Br. 20).
The second issue is whether Appellants have shown that the Examiner erred
in finding that Sarwary teaches generating a report indicating that the handshake
data exchange is identified in the IC design as recited in claims 2 and 14.

FINDINGS OF FACT
We adopt all of the Examiner’s findings of facts as set forth in the answer
(Ans. 6-8). We address in the analysis infra the following findings of fact (FF)
supported by a preponderance of the evidence:
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1. Sarwary teaches that the finite state machine (FSM) 230 generates a
“‘Ready’” signal indicating that data is ready to be transferred from clock
domain 210 to clock domain 220 (¶ [0016]).
2. Sarwary also teaches that a “‘Done’” signal is sent back to the first clock
domain 210 to enable new data to be loaded (¶ [0016]).
3. Sarwary teaches that at step S310 all clock-domain crossings are identified
in the IC design (¶ [0019]).
4. Sarwary further teaches searching the IC for a synchronization cell (Fig. 3,
step S330; ¶¶ [0012], [0019]).
5. Sarwary teaches that the structural synchronization cell includes a double
level register and a recirculation MUX, and that at step S340 a check is
performed to determine whether the structural synchronization cell was
found (Fig. 3, step S340; ¶ [0019]).
6. Sarwary teaches a single FSM serving as a source and destination FSM (Fig.
2, element 230).
7. Sarwary teaches finding all clock-domain crossings (FIG. 3, element S310),
and saving the clock-domain crossings in a list (¶ [0019]).

PRINCIPLES OF LAW
The Examiner bears the initial burden of presenting a prima facie case of
obviousness. In re Oetiker, 977 F.2d 1443, 1445 (Fed. Cir. 1992). If that burden is
met, then the burden shifts to the Appellants to overcome the prima facie case with
argument and/or evidence. Id.

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ANALYSIS
Regarding the rejection of claims 1, 3-7, 9-13, 15-19, and 21-24
Sarwary teaches that the finite state machine (FSM) 230 generates a
“‘Ready’” signal indicating that data is ready to be transferred from clock domain
210 to clock domain 220 (FF 1). Sarwary also teaches that a “‘Done’” signal is
sent back to the first clock domain 210 to enable new data to be loaded (FF 2).
Thus, Sarwary teaches a “request signal” (i.e., “‘Ready’” signal) and an
“acknowledge signal” (i.e., “‘Done’” signal). Accordingly, we are not persuaded
by Appellants’ argument that Sarwary teaches a method aimed at validating a
clock-domain crossing that does not include a handshake mechanism having a
“request signal” and an “acknowledge signal” (App. Br. 17-18). Furthermore,
Sarwary teaches that at step S310 all clock-domain crossings (i.e., handshake
mechanisms) are identified in the IC design (FF 3). Thus, Sarwary teaches
recognizing a handshake data exchange at a clock-domain crossing (FF 1-3) as
recited in the preamble of claims 1 and 13.
Sarwary further teaches searching the IC for a synchronization cell (FF 4).
Sarwary teaches that the structural synchronization cell includes a double level
register and a recirculation MUX and that at step S340 a check is performed to
determine whether the structural synchronization cell was found (i.e., identifying
the synchronization cell in the design) (FF 5). This characterization of structural
synchronization is consistent with Appellants’ structural analysis which is the
verification of an IC design by exploring the structure of the design (App. Br. 12),
by identifying synchronization cells in the design, such as double register level and
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a recirculation MUX (App. Br. 12). Thus, Sarwary does in fact perform a
structural analysis (FF 4-5) as described by Appellants (App. Br. 12).
Based on the above analysis, we are not persuaded by Appellants’ argument
(App. Br. 13-14) that Sarwary does not teach (1) performing a structural analysis
of an integrated circuit (IC) design (FF 4-5); (2) detecting at least one request
signal driven by the source FSM (FF 1); and (3) detecting at least one acknowledge
signal driven by the destination FSM (FF 2) as claimed. Sarwary teaches a single
FSM serving as a source and destination FSM (FF 6). We note that nothing in the
claim language precludes the same FSM from being both the source and
destination FSM.
For the foregoing reasons, Appellants have not persuaded us that the
Examiner erred in rejecting claim 1 and claims 3-7, 9-13, 15-19, and 21-24
which fall with claim 1.
Rejection of claims 2 and 14
Sarwary teaches finding all clock-domain crossings and saving the clock-
domain crossings in a list (FF 7). Thus, Sarwary teaches generating a report
indicating that the handshake data exchange is identified in the IC design as recited
in claims 2 and 14.

Rejection of claims 8 and 20
Regarding the obviousness rejections of claims 8 and 20 over Sarwary in
view of Rohrbaugh and/or Suaris, we find that Appellants have not persuasively
rebutted the Examiner's prima facie case of obviousness for these claims, but
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merely rely on the same arguments presented for claims 1 and 13 (App. Br. 20).
Once the Examiner has satisfied the burden of presenting a prima facie case
of obviousness, the burden then shifts to Appellants to present evidence and/or
arguments that persuasively rebut the Examiner's prima facie case. See Oetiker,
977 F.2d at 1445. Since Appellants did not particularly point out errors in the
Examiner’s reasoning to persuasively rebut the Examiner's prima facie case of
obviousness, the rejections are therefore sustained.

CONCLUSIONS
Appellants have not shown that the Examiner erred in rejecting claims 1-7,
9-19, and 21-24 under § 102. Nor have Appellants shown that the Examiner erred
in rejecting claims 8 and 20 under § 103.

ORDER
The decision of the Examiner to reject claims 1-24 is affirmed.
No time period for taking any subsequent action in connection with this
appeal may be extended under 37 C.F.R. § 1.136(a)(1)(iv).

AFFIRMED

KIS

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