5.8 HEURISTICS FOR CRMT MINIMIZATION 217
and
G
K-map YZ
= [W + (Y Z)] (X ⊕ Z )] (5.44)
with gate/input tallies of 5/10 and 4/8, respectively. Note that reading a K-map in maxterm
code requires that the domains (not the entered variables) be complemented, since the
K-maps are minterm-code based [3]. In comparison, the two-level minimum result from
Fig. 5.5a is
G = (W + X + Y )(W +
¯
X +
¯
Y )(
¯
W +
¯
X +
¯
Z )(
¯
W + X + Z), (5.45)
which has a gate/input tally of 5/16 excluding possible inverters.
Notice that all CRMT minimization results, the canonical R-M minimization result, and
one EV K-map result for G all represent three-level functions with minimum gate/input
tallies of 4/8 (excluding possible inverters). In comparison, the best two-level result that can ...