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The fastest speed occurs when the shape factor
r=√(
KP÷
KN×µ).
For a 3-NOR gate, we use KP=22/8;
KN=1, and µ=9/4,
which gives r=√(99/16)≈2.5.
This gives a P/N ratio of γ=0.9 which is lower than
γ=1 which we want to set as the minimum. For the fastest
gates then we will use P/N=1 which gives a shape factor
r=√=22/8=2.75.
This value has been used for the v1 version,
which are fast with unbalanced output skews.
The P/N ratio has been kept as close to 2 as possible for the v0
version in order to give more balanced output skews,
even if this is not the fastest configuration.
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