Ex parte Milazzo et al.

Board of Patent Appeals and Interferences

Nov 30, 2001

08621767 (B.P.A.I. Nov. 30, 2001)

The opinion in support of the decision being entered today was not
written for publication and is not binding precedent of the Board.
Paper No. 40
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte PATRIZIA MILAZZO, GREGORIO BONTEMPO and ANGELO ALZATI
____________
Appeal No. 1998-0824
Application No. 08/621,767
____________
ON BRIEF
____________
Before FLEMING, GROSS, and LEVY, Administrative Patent Judges.
FLEMING, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on appeal under 37 U.S.C. § 134 from
the final rejection of claims 1 through 37, all the claims
pending in the present application.
The present invention relates to output power stages
employing a power switch for connecting to a ground node a
load and wherein static power consumption within the driving
circuit is substantially eliminated.
Appeal No. 1998-0824
Application No. 08/621,767
2
Representative claim 1 reads as follows:
1. A low-side driver circuit, for use with an output power
transistor having a threshold voltage, comprising:
a first current generator which is electrically coupled
to receive and be controlled by a first switching signal, said
first current generator being electrically coupled to said
output power transistor to deliver a current, in response to
said first switching signal, for charging a driving node of
said output power transistor;
a second current generator electrically coupled to
receive and be controlled by a second switching signal which
is substantially complementary to said first switching signal,
and to deliver a current, in response to said second switching
signal but not said first switching signal, for discharging
said driving node of said output power transistor; and
control circuitry electrically coupled to said second
current generator and to said output power transistor, said
control circuitry being connected to prevent passage of
current through said second current generator when the output
power transistor is not conducting, said control circuitry
being controlled by a voltage at said driving node of said
output power transistor.
In rejecting Appellants' claims, the Examiner relies on
the following reference:
Takahashi 4,948,995 Aug.
14, 1990
Claims 1 through 37 stand rejected under 35 U.S.C. § 103
as being unpatentable over the prior art shown in Figure 6
Appeal No. 1998-0824
Application No. 08/621,767
Appellants filed an Appeal Brief on June 18, 1997. 1
Appellants filed a Reply Brief on October 31, 1997. The
Examiner mailed an Office Communication on January 16, 1998,
stating that the Reply Brief had been entered and considered
but no further response by the Examiner is deemed necessary.
The Examiner mailed an Examiner's Answer on September 2,2
1997. In response to Remand from the Board, the Examiner
mailed a Supplemental Examiner's Answer on May 9, 2001.
3
submitted by the Appellants in view of the teachings of
Takahashi.
Rather than reiterate the arguments of Appellants and the
Examiner, reference is made to the brief and answer for the1 2
respective details thereof.
OPINION
We will not sustain the rejection of claims 1 through 37
under 35 U.S.C. § 103.
In rejecting claims under 35 U.S.C. § 103, the Examiner
bears the initial burden of establishing a prima facie case of
obviousness. In re Oetiker, 977 F.2d 1443, 1445, 24 USPQ
1443, 1444 (Fed. Cir. 1992). See also In re Piasecki, 745
F.2d 1468, 1472, 223 USPQ 785, 788 (Fed. Cir. 1984). The
Examiner can satisfy this burden by showing that some
objective teaching in the prior art or knowledge generally
Appeal No. 1998-0824
Application No. 08/621,767
4
available to one of ordinary skill in the art suggests the
claimed subject matter. In re Fine, 837 F.2d 1071, 1074, 5
USPQ2d 1596, 1598 (Fed. Cir. 1988). Only if this initial
burden is met does the burden of coming forward with evidence
or argument shift to the Appellants. Oetiker, 977 F.2d at
1445, 24 USPQ at 1444. See also Piasecki, 745 F.2d at 1472,
233 USPQ at 788 ("After a prima facie case of obviousness has
been established, the burden of going forward shifts to the
applicant.").
An obviousness analysis commences with a review and
consideration of all the pertinent evidence and arguments.
See In re Oetiker, 977 F.2d at 1445, 24 USPQ at 1444. ("In
reviewing the examiner's decision on appeal, the Board must
necessarily weigh all of the evidence and arguments."). With
these principles in mind, we commence review of the pertinent
evidence and arguments of Appellants and Examiner.
The Examiner argues that Appellants' Figure 6 shows all
the claimed elements other than the control circuitry
electrically coupled to said second current generator and to
said output power transistor, said control circuitry being
Appeal No. 1998-0824
Application No. 08/621,767
5
connected to prevent passage of the current through the second
current generator when the output power transistor is not
conducting, said control circuitry being controlled by a
voltage at said driving node of said output power transistor.
The Examiner argues that Takahashi teaches and discloses the
main concept of using an output signal which is an input
signal to an associate stage to prevent unnecessary current
within a certain section of the circuit when the section is no
longer required for operation. The Examiner points us to
Figure 5 of Takahashi which shows output N12 of inverter 16
being fed back to control element of transistor 14. See page
5 of the Examiner's Answer. The Examiner argues that it would
have been obvious to one skilled in the art to use the basic
concepts taught and disclosed by Takahashi to place a
transistor/switch in the current path of the second current
generator 12 shown in Figure 6 of the prior art submitted by
the Appellants. See page 6 of the Examiner's Answer.
Appellants argue that the Examiner initially used
impermissibly the Appellants' inventive teachings that the
current consumption in the driver circuit may be intolerable
for certain applications as the basis for selectively
Appeal No. 1998-0824
Application No. 08/621,767
6
modifying the circuit of Figure 6. See page 5 of the Reply
Brief. Appellants argue that Takahashi must be viewed for
what the patent teaches as a whole and not what portions of
Takahashi that the Examiner can selectively choose from the
patent to somehow construct Appellants' claimed invention.
Appellants point out that Takahashi is a power-on-set circuit
and has nothing to do with Appellants' invention of a low-side
driver circuit. Appellants submit that there is no proper
motivation to combine the circuit of Appellants' Figure 6 with
Takahashi in any manner. See Reply Brief, pages 6 and 7.
The Examiner admits that Takahashi discloses a power-on
reset circuit and nothing to do with power transistors. See
page 3 of the Supplemental Examiner's Answer. The Examiner
further argues that Appellants have admitted that the problem
of unnecessary current consumption of the prior art Figure 6
circuit was known. The Examiner points us to page 5, lines 18
through 24, for this submission.
The Federal Circuit state that "[t]he mere fact that the
prior art may be modified in the manner suggested by the
Examiner does not make the modification obvious unless the
prior art suggested the desirability of the modification." In
Appeal No. 1998-0824
Application No. 08/621,767
7
re Fritch, 972 F.2d 1260, 1266 n.14, 23 USPQ2d 1780, 1783-84
n.14 (Fed. Cir. 1992), citing In re Gordon, 733 F.2d 900, 902,
221 USPQ 1125, 1127 (Fed. Cir. 1984). It is further
established that "[s]uch a suggestion may come . . . from the
nature of the problem to be solved, leading inventors to look
to references relating to possible solutions to that problem."
Pro-Mold & Tool Co. v. Great Lakes Plastics, Inc., 75 F.3d
1568, 1573, 37 USPQ2d 1626, 1630 (Fed. Cir. 1996), citing In
re Rinehart, 531 F.2d 1048, 1054, 189 USPQ 143, 149 (CCPA
1976) (considering the problem to be solved in a determination
of obviousness). The Federal Circuit reasons in Para-Ordnance
Mfg. Inc. v. SGS Importers Int'l Inc., 73 F.3d 1085, 1088-89,
37 USPQ2d 1237, 1239-40 (Fed. Cir. 1995), that for the
determination of obviousness, the court must answer whether
one of ordinary skill in the art who sets out to solve the
problem and who had before him in his workshop the prior art,
would have been reasonably expected to use the solution that
is claimed by the Appellants. However, "[o]bviousness may not
be established using hindsight or in view of the teachings or
suggestions of the invention." Para-Ordnance Mfg. v. SGS
Appeal No. 1998-0824
Application No. 08/621,767
8
Importers Int'l, 73 F.3d at 1087, 37 USPQ2d at 1239, citing W.
L. Gore & Assocs., Inc. v. Garlock, Inc., 721 F.2d at 1551,
1553, 220 USPQ at 311, 312-13. In addition, our reviewing
court requires the PTO to make specific findings on a
suggestion to combine prior art references. In re Dembiczak,
175 F.3d 994, 1000-01, 50 USPQ2d 1614, 1617-19 (Fed. Cir.
1999).
On our review of page 5 of the specification, we find
that Appellants have not admitted that the problem of
unnecessary current consumption of the prior art Figure 6 was
known. We agree that on page 5 of the specification
Appellants state that the Figure 6 circuit has a draw back
represented by the fact that when the power transistor Pw is
off, a certain current consumption occurs. However, we do not
find that the Appellants have stated that this fact was known
to others. Appellants are simply stating that they have
recognized the problem. Furthermore, even if we agreed with
the Examiner that somehow this was an admission by the
Appellants, there still is no admission that it was known what
the source of the problem was or the circuitry to correct the
Appeal No. 1998-0824
Application No. 08/621,767
9
problem; all of which is disclosed in later pages of
Appellants' specification.
Looking to Takahashi which discloses a disabling circuit
for a power-on event, we fail to find that this would lead
those skilled in the art to lift the transistor 14 shown in
Figure 5 and somehow modify Figure 6 to arrive at Appellants'
claimed invention which is shown in Figure 9. Even if we
could agree with the Examiner that the basic concept is taught
by Takahashi, we fail to find a teaching or suggestion on how
to connect the Takahashi transistor 14 into Appellants' Figure
6. We fail to find any suggestion or reason from the admitted
prior art, Figure 6, that there is a problem with power
consumption of the second current generator. Certainly, there
is no suggestion in Takahashi of this problem since Takahashi
is dealing with a completely different circuit. Therefore, we
find that the only suggestion for making a modification of
Appellants' Figure 6 is the Appellants' specification itself.
Therefore, we fail to find that the Examiner properly found
evidence of reasons or desirability of making the modification
in the prior art.
Appeal No. 1998-0824
Application No. 08/621,767
10
We have not sustained the rejection of claims 1 through
37 under 35 U.S.C. § 103. Accordingly, the Examiner's
decision is reversed.
REVERSED

MICHAEL R. FLEMING )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
ANITA PELLMAN GROSS ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
STUART S. LEVY )
Administrative Patent Judge )
MRF/LBG
Appeal No. 1998-0824
Application No. 08/621,767
11
CHRISTOPHER F. REGAN
ALLEN, DYER, DOPPELT, MILBRATH & GILCHRIST
255 S. ORANGE AVE., SUITE 1401
P.O. BOX 3791
ORLANDO, FL. 32802
Lesley
Appeal No. 1998-0824
Application No. 08/621,767
APJ FLEMING
APJ GROSS
APJ LEVY
DECISION: REVERSED

Prepared: July 19, 2002
Draft Final
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