1. Initial design:

Function    Mcells      FB Inps     Pterms      IO          
Block       Used/Tot    Used/Tot    Used/Tot    Used/Tot    
FB1          18/18*      30/54       49/90       8/ 9
FB2          17/18       26/54       38/90       4/ 9
FB3          18/18*      30/54       69/90       8/ 9
FB4          18/18*      32/54       48/90       7/ 7*
             -----       -----       -----      -----    
             71/72      118/216     204/360     27/34