Ex Parte Thomas

Board of Patent Appeals and Interferences

Sep 5, 2003

09300757 (B.P.A.I. Sep. 5, 2003)

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for publication and is not binding precedent of the Board.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. 17
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte THOMAS P. THOMAS
____________
Appeal No. 2002-0156
Application No. 09/300,757
____________
ON BRIEF
____________
Before KRASS, BARRY, and SAADAT, Administrative Patent Judges.
KRASS, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on appeal from the final rejection of claims 1-3. Rejections of
claims 6-10 and 22-25 have been withdrawn by the examiner and are no longer on
appeal before us.
The invention is directed to a phase frequency detector and is best illustrated by
reference to independent claim 1 reproduced as follows:
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Application No. 09/300,757
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1. An integrated circuit comprising: a phase-frequency detector (PFD) including
two clock input ports, an up signal port and a down signal port;
said PFD comprising digital circuitry including transistors coupled in a
configuration to adjust an amount of overlap of an up output signal pulse and a down
output signal pulse based, at least in part, upon the magnitude of an amount of phase
delay between two respective clock signal pulses applied to the two input ports.
The examiner relies on the following reference:
Noguchi 5,592,110 Jan. 7 1997
Claims 1-3 stand rejected under 35 U.S.C. §102 (e) as anticipated by Noguchi.
Reference is made to the briefs and answer for the respective positions of
appellant and the examiner.
OPINION
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Application No. 09/300,757
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The examiner indicates that Noguchi anticipates the instant claimed invention
because Figures 1 and 2 of Noguchi show a phase comparator (100) used in a phase
locked loop comprising two clock input ports for receiving clock signals (1 and 2) and
two output ports for providing up and down signal pulses, the phase comparator
comprising digital circuitry (figure 1 inherently includes transistors) coupled in a
configuration to adjust the amount of overlap of up and down output signal pulses
based, at least in part, upon the magnitude of an amount of phase delay between two
respective clock signal pulses (figures 2A-2B, 2F-2G) where the overlapping portion of
the up and down signals (figures 2F and 2G) varies accordingly to the phase
differences of the two received clock signals (1 and 2) as called for in claim 1 (see
answer-page 3).
It is appellant’s view that the illustration in Figures 2F and 2G of Noguchi shows
that the pulse width of the first output signal does not change regardless of the phase
delay between the two applied signals, the input signal and the reference signal.
Rather, according to appellant, Noguchi teaches the first and second output signal to
rise and fall based on the input signal, inverted signal, or the narrow width pulse,
referring to column 2, line 63 through column 3, line 5. Appellant points out that the
second output signal in Noguchi has a greater pulse width than the first output signal
and that if the phase delay between the input signal and the reference signal were
Appeal No. 2002-0156
Application No. 09/300,757
Page 4
increased, the pulse width of the first output signal would not increase, but the pulse
width of the second output signal would (principal brief-page 15). Appellant concludes
that
...although the magnitude of the phase delay between the
two signals may be increased, the amount of overlap between
the first output signal and the second output signal would
not increase (principal brief-pages 15-16, bold emphasis in the original).
We find that the examiner has established a prima facie case of anticipation
which has not been successfully rebutted by appellant’s argument.
With regard to Noguchi, Figure 2A is a waveform representative of the input
signal at terminal 1 in Figure 1; Figure 2B is a waveform representative of the
reference signal at terminal 2 in Figure 1; Figure 2F is a waveform representative of a
first output signal at (f) DOWN in Figure 1; and Figure 2G is a waveform representative
of a second output signal at (g) UP in Figure 1.
As seen in Figures 2F and 2G, the waveforms of the first and second output
signals, or the UP and DOWN signal pulses, overlap different amounts. For example,
starting from the left and moving toward the right, initially the pulse of the first output
signal overlaps about 2/3 of the second output signal pulse, then both pulses are
substantially equal, and, finally, the first output signal pulse overlaps the second output
Appeal No. 2002-0156
Application No. 09/300,757
Page 5
signal pulse completely, being approximately twice the width of the second output
signal pulse. Moreover, as we view these first and second output signal pulses with
respect to the two clock signal pulses, input signal at Figure 2A and reference signal at
Figure 2B, it appears clear that when the reference signal pulse lags behind the input
signal pulse by a certain magnitude, we get the condition that the first output signal
pulse overlaps the second output signal pulse by about 2/3 of the second output signal
pulse width. When the reference signal pulse is in phase with the input signal pulse,
the first and second output signal pulses also seem to exactly overlap each other.
Finally, when the input signal pulse lags behind the reference signal pulse, then the first
output signal pulse overlaps the second output signal pulse completely, approximately
twice the width of the second output signal pulse.
Clearly, then, the waveforms in Figures 2A, 2B, 2F and 2G of Noguchi show an
adjustment of an amount of overlap of an up output signal pulse and a down signal
pulse based, at least in part, upon the magnitude of an amount of phase delay between
two respective clock signal pulses applied to the two input ports, as claimed.
Appellant’s argument regarding the pulse width of the first output signal not
changing regardless of the phase delay between the two applied signals is not
persuasive because the argument is not based on claimed limitations. In accordance
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Application No. 09/300,757
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with claim 1, it is not necessary that the pulse width of the first output signal (DOWN)
change in response to the phase delay between the two applied signals. The claim
only requires that the “amount of overlap” between the up and down signal pulses be
adjusted based, at least in part, upon the magnitude of the phase delay between the
two applied signals. As discussed supra, Noguchi clearly discloses the claimed
relationship. Likewise, appellant’s argument that the first and second output signals of
Noguchi have different pulse widths is not persuasive because the claim language says
nothing about the actual pulse widths of these signals; it is concerned only with the
“amount of overlap” of these signals and the adjustment of that overlap based, at least
in part, upon the magnitude of the phase delay between the two applied signals.
Since none of appellant’s arguments are persuasive of error in the examiner’s
position, and claims 2 and 3 will stand or fall with claim 1, in accordance with the
grouping of claims at page 6 of the principal brief, we will sustain the examiner’s
rejection of claims 1-3 under 35 U.S.C. §102 (e).
The examiner’s decision is affirmed.
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Application No. 09/300,757
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No period for taking any subsequent action in connection with this appeal may
be extended under 37 CFR § 1.136(a).
AFFIRMED
ERROL A. KRASS )
Administrative Patent Judge )
)
)
) BOARD OF PATENT
LANCE LEONARD BARRY ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
MAHSHID D. SAADAT )
Administrative Patent Judge )
EAK/yrt
Appeal No. 2002-0156
Application No. 09/300,757
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Michael Nesheiwat, Esq.
BLAKELY, SOKOLOFF, TAYLOR & ZAFMAN
12400 Wilshire Boulevard, Seventh Floor
Los Angeles, CA 90025-1026
Tel: 408-720-8598