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2-OR Gate Made from 2-NAND with Inverted Inputs - nd2ab

   
gate count               1480
number of cells           666
number of library cells    79
number of used cells       34
max fanin                  17
max input capacitance     187
max internal fanout        34
critical path  0fF       2300
critical path  6fF       2963
   nd2ab nd2ab symbol

This 2-OR gate implementation is faster, but bigger and more power hungry than a regular 2-NOR followed by an inverter. In this netlist it has no effect, as only two 2-OR gates are chosen by BOOG, and because neither of these is on the critical path, they remain as or2v0x05 cells.

Table of synthesis results  
  critical path (ps) gate count cell count porosity library cells used cells
synthesis 1 4279 1561 923 43%  9  8 basic inverters, NAND & NOR gates
synthesis 2 4236 1472 792 45% 15 12 AND & OR gates
synthesis 3 4157 1357 696 46% 19 16 AOI & OAI gates, 2/1 and 2/2
synthesis 4 4157 1357 696 46% 20 16 mxi2 2-way inverting mux
synthesis 5 3983 1343 668 48% 21 16 cgi2 carry generator inverting
synthesis 6 3948 1352 668 48% 28 18 inverters with multiple drive strengths
synthesis 7 3061 1433 666 51% 70 27 x2 drive strengths for all functions
synthesis 8 3056 1456 666 52% 70 30 BOOG with x1 drive strengths
synthesis 9 2960 1476 666 53% 70 32 BOOG with x05 drive strengths
synthesis 10 2963 1480 666 53% 76 34 nd2a and nr2a cells
synthesis 11 2963 1480 666 53% 79 34 nd2ab type of 2-OR