Appeal No. 2004-0607
Application No. 09/792,848
that is normally set to zero volts and called GROUND (GND) or
VSS” and that “[t]he power supplies (VDD and VSS) are the source of
the strongest ‘1’s and ‘0’s.” Other sources indicate that Vss
often means negative supply or ground, but that its meaning is
determined by its usage.2 Whether Vss always is the lowest
voltage available on the chip is questionable in view of
Momohara’s disclosures that VSS can be ground potential and that
a P-well can be biased with negative voltage VBB (col. 9,
lines 32-33; col. 10, lines 39-40).
Regardless, even if Vss is the lowest voltage available on
the chip, the record does not indicate that the appellant had
possession of a circuit in which a P-well is biased by a bias
potential above Vss. The appellant argues that “[t]he
specification states that by varying the bias applied to the
P-well, the performance of the device may be improved and that by
using a higher bias potential on the P-well, better high
frequency performance can be achieved. Necessarily, then, the
2 See “CMOS Logic”, in “Application-Specific Integrated
Circuits” (Addison Wesley Longman 1997), http://www-
ee.eng.hawaii.edu/~msmith/ASICs/HTML/Book/CH02/CH02.htm; “Vcc,
Vdd, Vss, etc.”,
wysiwyg://main.20/http://encyclobeamia.solarbotics.net/articles/v
xx.html; “Electronic Symbols”,
http://www.control.com/1026184337/index_html. Copies of these
references are provided to the appellant with this decision.
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