Ex Parte Guo

Patent Trial and Appeal Board

Jan 13, 2016

12420047 (P.T.A.B. Jan. 13, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
12/420,047 0410712009
58377 7590 01/15/2016
MENTOR GRAPHICS CORP,
PA TENT GROUP
8005 SW BOECKMAN ROAD
WILSONVILLE, OR 97070-7777
FIRST NAMED INVENTOR
Ruifeng Guo
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www .uspto.gov
ATTORNEY DOCKET NO. CONFIRMATION NO.
10498-REGl/XY 1741
EXAMINER
NGUYEN, STEVEN
ART UNIT PAPER NUMBER
2117
NOTIFICATION DATE DELIVERY MODE
01115/2016 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address( es):
patent_group@mentor.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte RUIFENG GUO
Appeal2014-004076 1
Application 12/420,047
Technology Center 2100
Before CHARLES J. BOUDREAU, NORMAN H. BEAMER,
and ADAM J. PYONIN, Administrative Patent Judges.
BEAMER, Administrative Patent Judge.
DECISION ON APPEAL
Appellant appeals under 35 U.S.C. § 134(a) from the Examiner's
Final Rejection of claims 4--10 and 12-14.2 Claims 1-3 and 11 are
cancelled. We have jurisdiction over the pending claims under
35 U.S.C. § 6(b).
We affirm.
1 An oral hearing was held January 8, 2016.
2 Appellant identifies Mentor Graphics Corporation as the real party in
interest. (Br. 3.)
Appeal2014-004076
Application 12/420,047
THE INVENTION
Appellant's invention is directed to a debug flow that uses debug-
friendly test patterns and logic fault diagnosis techniques to help physical
fault isolation of timing failures. (Abstract.) Claim 4, reproduced below, is
illustrative of the claimed subject matter:
4. A method of timing failure debug, comprising:
selecting a target signal region in a circuit where a
timing-related defect may exist and a propagation path that
passes through the target signal region to an observation point
where a timing failure caused by the timing-related defect can
be observed;
generating, under one or more constraints, a test pattern
that can, at least through scan cells, activate the timing-related
defect and propagate the timing failure along the propagation
path, the one or more constraints including a first constraint that
some or all side inputs along the propagation path are set to
non-controlling values;
applying the test pattern to the circuit; and
monitoring directly a portion of the propagation path at a
time using a physical isolation technique for transition signal
measurement to locate the timing-related defect, the portion of
the propagation path comprising one or more components of the
circuit.
REJECTIONS 3
The Examiner rejected claims 4, 12, and 14 under 35 U.S.C. § 103(a)
as being unpatentable over Arabi et al. (US 6,233 ,314 B 1, issued Apr. 24,
3 The Examiner has withdrawn rejections of claims 4--10 and 12-14 under
35 U.S.C. § 112, first and second paragraphs. (Ans. 2.)
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Application 12/420,047
2001), Beausang et al. (US 5,696,771, issued Dec. 9, 1997) and Kasapi
(US 6,976,234 B2, issued Dec. 13, 2005). (Final Act. 5-7.)
The Examiner rejected claims 5-7 and 9-10 under 35 U.S.C. § 103(a)
as being unpatentable over Arabi, Beausang, Kasapi, and Crouch et al.
(US 5,592,493, issued Jan. 7, 1997). (Final Act. 7-9.)
The Examiner rejected claim 8 under 35 U.S.C. § 103(a) as being
unpatentable over Arabi, Beausang, Kasapi, and Jian Kang et al., Symbolic
Path Sensitization Analysis and Applications, IEEE Asian Test Symposium,
439-44 (Oct. 2007). (Final Act. 9-10.)
The Examiner rejected claim 13 under 35 U.S.C. § 103(a) as being
unpatentable over Arabi, Beausang, Kasapi, and Hiraide (US 7,266,746 B2,
issued Sept. 4, 2007). (Final Act. 10-11.)
ISSUES ON APPEAL
Appellant's arguments in the Appeal Brief present the following
issues: 4
Issue One: Whether the combination of Arabi, Beausang, and Kasapi
teaches or suggests the independent claim 4 limitation, "generating, under
one or more constraints, a test pattern that can, at least through scan cells,
activate the timing-related defect and propagate the timing failure along the
propagation path." (Br. 9-10.)
4 Rather than reiterate the arguments of Appellant and positions of the
Examiner, we refer to the Appeal Brief (filed Sept. 30, 2013), Final Office
Action (mailed Oct. 29, 2012), and the Examiner's Answer (mailed Oct. 25,
2013) for the respective details.
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Application 12/420,047
Issue T'wo: Whether the combination of Arabi, Beausang, and Kasapi
teaches or suggests the independent claim 4 limitation, "monitoring directly
a portion of the propagation path at a time using a physical isolation
technique for transition signal measurement to locate the timing-related
defect." (Br. 4--9.)
ANALYSIS
We have reviewed the Examiner's rejections in light of Appellant's
arguments that the Examiner has erred. We disagree with Appellant's
arguments, adopt as our own ( 1) the findings and reasons set forth by the
Examiner in the action from which this appeal is taken (Final Act. 5-11) and
(2) the reasons set forth by the Examiner in the Examiner's Answer in
response to Appellant's Appeal Brief (Ans. 2-6), and concur with the
conclusions reached by the Examiner. We emphasize the following.
Issue One
Appellant argues that the Examiner errs in finding Arabi, Beausang,
and Kasapi teach or suggest "generating, under one or more constraints, a
test pattern that can, at least through scan cells, activate the timing-related
defect and propagate the timing failure along the propagation path." (Br. 9-
10.) For this finding, the Examiner relies on the disclosure in Arabi showing
a test pattern applied to the path being monitored to locate a timing-related
defect, together with the disclosure in Beausang of the use of scan cells.
(Final Act. 5---6; Arabi Fig. 3, element 48, Figs. 5, 1 O; Beausang Fig. 3B,
element 320, col. 10, 11. 22-26.) The Examiner finds "it would have been
obvious to a person of ordinary skill in the art at the time the invention was
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Appeal2014-004076
Application 12/420,047
made to replace the input multiplexing chain 64 [in Fig. 1 OJ of Arabi with
the multiplexed scan cells 320 [in Fig. 3B] of Beausang." (Final Act. 6.)
Appellant argues that the replacement relied on by the Examiner
"does not change the fact that it is through primary inputs exclusively that
the timing-related defect is activated and the timing failure propagated along
the propagation path," and further argues neither Beausang nor Arabi
discloses generating a test pattern. (Br. 10.) However, we are not persuaded
that the Examiner errs in finding:
[T]he path 64 in Arabi, when replaced with the scan path 320 of
Beausang would have introduced scan cells in the path as
shown by Beausang in Fig. 3B, 321. Arabi teaches applying
the test pattern through the multiplexer path (col. 5, lines 50-
53). The scan path of Beausang in Fig. 3B, further includes
scan cells 321. As well-known by a skilled artisan, scan cells
are used to introduce test patterns into the circuit to allow for
easier testability and observability. Therefore the combination
teaches "at least through scan cells."
(Ans. 5.)5 Furthermore; as the Examiner finds; and contrary to Appellant's
argument, Arabi discloses a test pattern. (Ans. 6; Arabi Fig. 2.)
Issue Two
Appellant argues that the Examiner errs in finding Arabi, Beausang,
and Kasapi teach or suggest "monitoring directly a portion of the
propagation path at a time using a physical isolation technique for transition
signal measurement to locate the timing-related defect." (Br. 4--9.) For this
finding, the Examiner relies on the disclosure in Arabi showing monitoring a
portion of a propagation path to locate a timing-related defect, together with
5 Separately, we note the disputed limitation recites optional language (i.e.,
"can"), which does not narrow the claim because such language can always
be omitted. See In re Johnson, 435 F.3d 1381, 1384 (Fed. Cir. 2006).
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Appeal2014-004076
Application 12/420,047
the disclosure in Kasapi of the use of time-resolved emission techniques.
(Final Act. 6-7; Arabi Fig. 5; Kasapi col. 5, 1. 65---col. 6, 1. 1.)
Appellant argues, because Arabi measures oscillation frequency, it
monitors the whole target path, rather than a portion thereof. (Br. 5.)
Further, Appellant argues that the physical isolation technique described in
Kasapi does not directly monitor the circuit under test because a signal
analysis circuit must be inserted therein, and the Kasapi technique does not
measure signals along a propagation path. (Br. 6-7.) Finally, Appellant
argues that the Examiner errs in combining Arabi with Kasapi because
neither reference "relates to locating timing-related defects," Kasapi
discloses inserting signal analysis circuit prior to manufacture of the chip,
and the combination requires inserting additional non-functional devices into
the circuit. (Br. 7-9.)
We are not persuaded by these arguments. As the Examiner points
out, "monitoring the whole target path as Appellant admits is done by Arabi
necessarily includes monitoring a portion of the path." (Ans. 2.) In
addition, Arabi does in fact disclose monitoring less than the entire path.
(Ans. 3; Arabi Fig. 10 (multiplexer 64.)) Furthermore, we are not persuaded
that the Examiner errs in finding, "[T]he signal analysis circuit of Kasapi is
merely the mechanism that monitors the path for a defect, and therefore the
path is monitored directly by the signal analysis circuit .... " (Ans. 3.)
Moreover, as the Examiner states, the rejection is based on a combination of
references, and to that end "the time-resolved emission technique of Kasapi
was applied to the propagation path of Arabi," and thus it is not persuasive
to argue that Kasapi does not measure signals along a propagation path.
(Ans. 4.) See In re Keller, 642 F.2d 413, 426 (CCPA 1981) ("But one
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Application 12/420,047
cannot show non-obviousness by attacking references individually where, as
here, the rejections are based on combinations of references.").
Nor are we persuaded that the Examiner errs in combining Arabi with
Kasapi. The Examiner's response cites the fact that Arabi teaches locating
timing-related defects; and Kasapi discloses performing the time-resolve
emission detection technique after the chip is manufactured. (Ans. 4; Arabi
Fig. 3, element 48; Kasapi col. 7, 11. 24--28.) Furthermore, we are not
persuaded that the Examiner errs in finding:
[T]he signal analysis circuit of Kasapi is intended to test a chip,
and therefore it would have been within the technical grasp of a
person of ordinary skill in the art at the time the invention was
made to build the proposed combination to test the circuitry of
Arabi and understand the engineering tradeoffs involved.
(Ans. 5.)
CONCLUSION
For the reasons discussed above, we sustain the obviousness rejection
of claim 4 over Arabi, Beausang, and Kasapi.
We also sustain the obviousness rejections of (i) claims 12 and 14
over Arabi, Beausang, and Kasapi; (ii) claims 5-7, and 9-10 over Arabi,
Beausang, Kasapi, and Crouch; (iii) claim 8 over Arabi, Beausang, Kasapi,
and Kang; and (iv) claim 13 over Arabi, Beausang, Kasapi, and Hiraide,
which rejections are not argued separately with particularity. (Br. 11.)
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Application 12/420,047
DECISION
The Examiner's rejection of claims 4--10 and 12-14 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)(l )(iv).
AFFIRMED
hh
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