Ex parte Marshall

Board of Patent Appeals and Interferences

Feb 29, 2000

08642811 (B.P.A.I. Feb. 29, 2000)

1
Paper No. 25
THIS OPINION WAS NOT WRITTEN FOR PUBLICATION
The opinion in support of the decision being entered today
(1) was not written for publication in a law journal and
(2) is not binding precedent of the Board.
UNITED STATES PATENT AND TRADEMARK OFFICE
_______________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
_______________
Ex parte ANDREW MARSHALL
______________
Appeal No. 1997-1389
Application 08/642,811
_______________
ON BRIEF
_______________
Before THOMAS, FLEMING and GROSS, Administrative Patent
Judges.
THOMAS, Administrative Patent Judge.

DECISION ON APPEAL
Appellant has appealed to the Board from the examiner's
final rejection of claims 1 through 5, which constitute all
the claims in the application.
Representative claim 1 is reproduced below:
1. A bridge control circuit for substantially
eliminating shoot-through current comprising:
Appeal No. 1997-1389
Application 08/642,811
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an H-bridge circuit; and
active feedback circuity coupled to said H-bridge circuit
to detect a predetermined half H-bridge output voltage level,
and upon said detection enabling turn on of next phase of a
drive sequence.
The following references are relied on by the examiner:
Hattori 5,057,720 Oct. 15, 1991
Fukunaga 5,099,138 Mar. 24, 1992
Wilcox 5,408,150 Apr. 18, 1995
(filed Mar. 22, 1993)
Claims 1 through 5 stand rejected under 35 U.S.C. § 112,
second paragraph, because, in the examiner's view, the
language “next phase” and “drive sequence” at the end of claim
1 are not clearly defined and are thus vague and indefinite.
Claim 1 stands rejected under 35 U.S.C. § 102(b) as being
anticipated by either Hattori or Fukunaga. Claim 1 also
stands rejected under 35 U.S.C. § 102(e) as being anticipated
by Wilcox.
Rather the repeat the positions of the appellant and the
examiner, reference is made to the brief and the answer for
the respective details thereof.
OPINION
Appeal No. 1997-1389
Application 08/642,811
3
Turning first to the rejection of claims 1 through 5
under the second paragraph of 35 U.S.C. § 112, it is to be
noted that to comply with the requirements of the cited
paragraph, a claim must set out and circumscribe a particular
area with a reasonable degree of precision and particularity
when read in light of the disclosure and the teachings of the
prior art as it would be by the artisan. Note In re Johnson,
558 F.2d 1008, 1016, 194 USPQ 187, 194 (CCPA 1977); In re
Moore, 439 F.2d 1232, 1235, 169 USPQ 236, 238 (CCPA 1971).
We have reviewed and considered the examiner’s reasons in
support of the rejection, but are not convinced that the cited
claims fail to comply with the second paragraph of 35 U.S.C. §
112. At the outset, we note that the breadth of the claims is
not equated with indefiniteness of the claims. See In re
Miller, 441 F.2d 689, 693, 169 USPQ 597, 600 (CCPA 1971). It
is perfectly permissible for appellant to claim his invention
in terms as broad as his application disclosure will support.
The examiner's concerns with respect to the next phase of
a drive sequence set forth at the end of claim 1 on appeal
relate to a more restrictive view of the second paragraph of
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Application 08/642,811
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35 U.S.C. § 112 than is required by the above noted precedent.
The examiner appears to desire more than a reasonable degree
of precision and particularity of the claim when read in the
absence of the disclosed invention and in the absence of the
teachings of the prior art. The examiner's remarks at pages 3
and 5 of the answer are without these key contexts.
Appellant's remarks at page 4 of the brief properly set forth
these contexts of the above-noted case law. We agree with
appellant's general view there that the meaning of the
questioned terms may be properly construed by an artisan in
the context of the type of motor being driven by the H-bridge
circuit. Granted, representative claim 1 is somewhat broad in
many respects, however, in our view, it is not so broad as to
be indefinite. Therefore, we reverse the rejection of claims
1 through 5 under the second paragraph of
35 U.S.C. § 112.
As to the section 102 rejection of claim 1 in light
Hattori, we reverse this rejection. The examiner does not
assert in the rejection at pages 3 and 4 of the answer and in
the responsive arguments portion of the answer at page 6 that
the apparent feedback circuitry comprising the two transistors
Appeal No. 1997-1389
Application 08/642,811
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14 and 15 in Hattori operate upon the detection of a
predetermined half H-bridge output voltage level. Inasmuch as
this reference is the same reference discussed by appellant at
page 2 of the specification as filed, appellant notes there
that Hattori's circuit cannot be used with a half H-bridge
circuit. Furthermore, as noted by appellant at the top of
page 6 of the brief, Hattori's detection does not enable the
turn on of a next phase of the drive sequence. A next phase
of a drive sequence in Hattori is inevitable, but it is not
enabled by the detection operation of the active feedback
circuitry claimed. There is no feedback of transistors 14, 15
to the control circuit 11 in Hattori.
On the other hand, we sustain the rejection of claim 1
under 35 U.S.C. § 102 as being anticipated by Fukunaga for the
reasons set forth by the examiner at pages 4, 7 and 8 of the
answer. As noted by the examiner, the context of the specific
disclosure in this reference is with respect to the three
phrase bridge circuit set forth in prior art Figure 1 of
Fukunaga for the motor 1. As noted by the examiner in the
rejection, the midpoint between the upper power switch devices
2U, 3U, 4U and the lower power switching device 2L, 3L, and 4L
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Application 08/642,811
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in Figure 1 comprises the claimed output of what amounts to
half of the claimed H-bridge. Figure 5 is the basic block
diagram circuit which is detailed in certain portions in
Figure 6 which the examiner discusses in detail.
The monitoring circuit 13U, 13L is shown in Figure 5 and
shown in more detail in Figure 6. As noted in the abstract of
this reference, it would appear by inspection of Figure 5 that
the monitoring circuits 13U, 13L are connected respectively
only to the power switching devices 2U, 2L. However, in
accordance with the showing in Figure 6 in the discussion with
respect to this figure beginning at the bottom of column 4, it
is noted that the apparent monitoring voltage V , V is “basedGL GU
on” an emitter voltage V , V . Note the paragraph bridgingEL EU
columns 4 and 5. It is clear from the showing of Figure 10
that the switching devices 2U, 2L may utilize a current
detecting transistor which utilizes the output of V “basedMON
on” the voltage output from the current detector resistor 20
which is connected again to the emitter portion V , V . TheEU EL
voltage developed at V through the current detectingMON
resistor 20 is based upon the current flowing through the
entire transistor 19U, 19L in Figure 10. Note the discussion
Appeal No. 1997-1389
Application 08/642,811
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in the paragraph bridging columns 6 and 7 of Fukunaga. As
well pointed out by the examiner in the noted portions in the
answer, Figures 12 and 13 make it clear that a current
transformer and a current detecting resistor may be utilized
in the alternative “to derive a voltage . . . in response to a
main current flowing in the switching device 2U (2L) through
an amplifier 25 as a monitor voltage V .” (column 7, linesMON
15 through 20.)
In view of the foregoing assessment of this reference, it
is clear that there is detection of an output voltage of a
half
H-bridge circuit as set forth at the end of claim 1 on appeal
to enable subsequent drive sequences through the other logic
feedback circuitry of Figures 5 and 6. We find unpersuasive,
as does the examiner, appellant's discussion of this reference
at pages 6 and 7 of the brief. As noted by the examiner,
appellant's discussion with respect to Figure 10 relates
primarily to features not pertinent to the claimed invention
recited in claim 1 on appeal. Therefore, we sustain the
rejection of claim 1 under 35 U.S.C. § 102 as being
anticipated by Fukunaga.
Appeal No. 1997-1389
Application 08/642,811
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Finally, we turn to the rejection of claim 1 under 35
U.S.C. § 102 as being anticipated by Wilcox. We sustain this
rejection for the reasons set forth by the examiner in the
paragraph bridging pages 4 and 5 of the answer as well as the
responsive arguments addressed to this rejection at pages 8
and 9 of the answer. Appellant's brief remarks with respect
to this rejection at page 9 of the brief are, at best,
incomplete. Although the Figure 2 embodiment of Wilcox's
half-bridge circuit does monitor the gate drive voltages of
transistors 21 and 22 by means of top gate feedback node 33
and bottom gate feedback 35, the reference shows in Figure 2 a
so-called top source feedback node 34 which clearly is shown
to monitor the output voltage feeding the output node 26 for
the load 24 where this node 26 is located between the
transistors 21 and 22.
The discussion beginning at column 4, line 38 with
respect to Figure 2 in Wilcox clearly indicates that the logic
circuit 32 in fact controls the turning on and off of the
respective transistors 21 and 22 based upon this feedback
information derived from transistors 21 and 22, thus meeting
the enabling language feature at the end of claim 1 on appeal.
Appeal No. 1997-1389
Application 08/642,811
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The discussion of the first two paragraphs of column 5 of this
reference also indicate that the logic circuit 32 operates to
reduce or prevent the occurrence of shoot-through voltages
associated with respect to transistors 21 and 22. Thus, these
teachings clearly meet the end use limitation of the preamble
of claim 1 on appeal “for substantially eliminating shoot-
through current” to the extent this limitation breathes any
life or meaning into the body of claim 1 on appeal.
Attention is also directed to the Figure 8 embodiment
discussed at the middle of column 8 which shows a comparable
circuit to Figure 2 but utilizes instead a bootstrap bias
detector 71 connected to the midpoint of the transistors 21
and 22 at the output thereof, where the circuit 70 feeds
directly into the logic circuit 65, which circuit generally is
taught to control the switching transistors 21 and 22. The
enablement feature at the end of claim 1 is taught in the same
words at column 9, lines 22 through 26 with respect to Figure
8's more detailed showings in Figure 9.
In summary, we have sustained two of the three rejections
under 35 U.S.C. § 102 of claim 1 on appeal but have reversed
Appeal No. 1997-1389
Application 08/642,811
10
the rejection of claims 1 through 5 under the second paragraph
of
35 U.S.C. § 112. Accordingly, the decision of the examiner is
affirmed-in-part.
AFFIRMED-IN-PART
JAMES D. THOMAS )
Administrative Patent Judge )
)
)
)
MICHAEL R. FLEMING ) BOARD OF PATENT
Administrative Patent Judge ) APPEALS AND
) INTERFERENCES
)
ANITA PELLMAN GROSS )
Administrative Patent Judge )
JDT/cam
Rose Alyssa Keagy
Texas Instruments Incorporated
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Dallas, TX 75265