Ex Parte Teene

Board of Patent Appeals and Interferences

Sep 24, 2002

08650248 (B.P.A.I. Sep. 24, 2002)

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The opinion in support of the decision being entered
today was not written for publication in a law journal
and is not binding precedent of the Board.
Paper No. 24
UNITED STATES PATENT AND TRADEMARK OFFICE

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES

Ex parte ANDRES R. TEENE

Appeal No. 2001-0632
Application No. 08/650,248

ON BRIEF

Before THOMAS, KRASS and SAADAT, Administrative Patent Judges.
KRASS, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on appeal from the final rejection of
claims 1-12, all of the pending claims.
The invention is directed to various embodiments for
eliminating scan hold time failures of a scan chain.
Representative independent claim 1 is reproduced as follows:
1. A method for eliminating scan hold time failures of a
scan chain comprising the steps of:
Appeal No. 2001-0632
Application No. 08/650,248
1A supplemental brief was filed on October 16, 2000, merely
to comply with 37 CFR 1.192 (c)(1)(2) by listing the real party
of interest and any related appeals.
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distributing a clock signal; and
ordering the scan chain according to the distribution of the
clock signal.
The examiner relies on the following references:
Lim et al. [Lim] 5,481,209 Jan. 02, 1996
Meltzer 5,502,731 Mar. 26, 1996
Claims 1-12 stand rejected under 35 U.S.C. 103 as
unpatentable over Lim in view of Meltzer.
Reference is made to the briefs1 and answer for the
respective positions of appellant and the examiner.
OPINION
The initial burden is on the examiner to establish a prima
facie case of obviousness, when rejecting a claim under 35 U.S.C.
103. This is done by establishing the level of skill of the
skilled artisan, determining the differences between the instant
claimed subject matter and the prior art references and providing
a convincing rationale as to why the instant claimed subject
Appeal No. 2001-0632
Application No. 08/650,248
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matter as a whole would have been obvious to the artisan in view
of the applied references.
In the instant case, while the instant claimed subject
matter appears rather broad in scope, the examiner has simply not
established such a prima facie case of obviousness.
Taking claim 1 as exemplary, the examiner has stated that
Lim teaches a clock distribution with reduced clock skew but
recognizes that Lim fails to disclose the ordering of a scan
chain according to the distribution of the clock signal. The
examiner turns to Meltzer for a teaching of shift register
latches interconnected into scan chains, wherein the shift
register latches are ordered in accordance with the amount of
circuit outputs controlled. While this much appears to be true,
the examiner then concludes that it would have been obvious to
“modify the method of Lim that minimize clock skew, and reduces
the length of clock signal tributaries to include SRL latches as
taught by Meltzer in place of local buffers and ordering the
latches according to the distribution of the clock signal”
[answer-page 4]. The examiner has given absolutely no basis for
substituting SRL latches in place of local buffers in Lim and
then ordering the latches according to the distribution of the
clock signal in Lim. Merely because Lim teaches a clock
Appeal No. 2001-0632
Application No. 08/650,248
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distribution for reducing clock skew and Meltzer teaches ordering
of SRLs in a scan chain, that is no reason to take only so much
from each reference as needed for a particular claim and forcibly
combine the two teachings to reach the instant claimed subject
matter. There must be some suggestion in the prior art, or some
reason for the artisan, to make the modification, other than what
is taught by appellant.
The examiner further explains that Lim provides motivation
by teaching advantages that include reduction in delay between
buffers and reduction in tributary length “which are highly
advantageous to the scan based test design taught by Meltzer” and
that Meltzer “expresses desirability to achieve maximum delay
fault coverage while Lim’s invention provides reduced delay
between buffers thus providing motivation...” [answer-pages 4-5].
We disagree. There is no suggestion in Lim that the invention
described therein would have any utility in a scan based test
design or in the ordering of scan chains. There is no suggestion
that Lim’s distribution of a clock signal would have any utility
in a scan chain of SRLs as taught by Meltzer. Accordingly, we
cannot accept the examiner’s reasoning as a convincing rationale
for making the combination in such a manner as to establish
obviousness in accordance with 35 U.S.C. 103.
Appeal No. 2001-0632
Application No. 08/650,248
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There are similar problems with the examiner’s rationale as
applied to the other independent claims. Accordingly, we will
not sustain the rejection of claims 1-12 under 35 U.S.C. 103.
Our decision herein should not be taken as an affirmation of
the patentability of the rather broad instant claimed subject
matter, but, rather, only that the examiner has not made a proper
rejection of the claimed subject matter under 35 U.S.C. 103. To
deny a patent on the broadest instant claimed subject matter, the
examiner would need to show no more than a disclosure or a
suggestion in the prior art of merely ordering a scan chain
according to, or, in some way, related to, the distribution of a
clock signal. This the examiner has not done.
Appeal No. 2001-0632
Application No. 08/650,248
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The examiner’s decision rejecting claims 1-12 under
35 U.S.C. 103 is reversed.
REVERSED
JAMES D. THOMAS )
Administrative Patent Judge )
)
)
)
)
ERROL A. KRASS ) BOARD OF PATENT
Administrative Patent Judge ) APPEALS AND
) INTERFERENCES
)
)
)
MAHSHID D. SAADAT )
Administrative Patent Judge )
Appeal No. 2001-0632
Application No. 08/650,248
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