Appeal No. 1997-2297 Page 13
Application No. 08/337,636
hysteresis transistors that have the same gate width as the
drive transistors (col. 3, lines 39-45 and col. 4, lines 35-
39), McClure still discloses that it is conventional for the
drive transistors 2n to be three to five times the size of the
drive transistors 2p depending on the threshold voltage. From
these teachings of the prior art, we find that an artisan
would have been taught that the pull-down transistors be five
times the size of the pull-up transistors.
Appellants further assert (brief, page 5) that the ratios
disclosed in the references and used in the rejections are not
the ratios claimed. We note that claim 10 additionally
recites, similar to claim 1 but somewhat broader, that the
first gate size of a pull-down device of the buffer is greater
than the first gate size. As Koker discloses (col. 8, lines
8-17) that the inverter INV1 has a gate width that is the same
6 micron size as the width of transistor P1pa, and McClure is
silent as to the size of the inverter, we find that the prior
art does not teach or suggest that the first input gate size
of a pull-down device of the buffer is greater than the first
gate size, as recited in claim 10. Accordingly, we cannot
sustain the examiner's rejection of claim 10, or claim 11
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