CS 14 -- Problem set 1


Combinational Logic and Their Circuits

Answer the questions below clearly and completely. This assignment is due Monday, February 13th at 10:00 am.


  1. For each of the Boolean functions described by the truth table below:

    1. Use Karnaugh maps to derive a simplified form of the function.
    2. Draw the circuit implied by the simplified function.
    3. Draw the ROM-based circuit that would implement this function.
    a.
    	A   B   C   Output
    	------------------
    	0   0   0        1
    	0   0   1        1
    	0   1   0        0
    	0   1   1        0
    	1   0   0        1
    	1   0   1        1
    	1   1   0        0
    	1   1   1        1
    
    b.
    	A   B   C   D   Output
    	----------------------
    	0   0   0   0        1
    	0   0   0   1        1
    	0   0   1   0        1
    	0   0   1   1        0
    	0   1   0   0        0
    	0   1   0   1        0
    	0   1   1   0        1
    	0   1   1   1        0
    	1   0   0   0        1
    	1   0   0   1        1
    	1   0   1   0        1
    	1   0   1   1        0
    	1   1   0   0        1
    	1   1   0   1        1
    	1   1   1   0        0
    	1   1   1   1        1
    	
  2. Convert the following formula from DNF (sum-of-products) to CNF (product-of-sums) form:
          _ _       _ _
      Y = A B C + A B C
    	
  3. Prove using only algebraic manipulation that the following two expressions are equivalent:
      _     _
      A B + A C
      _     _ _
      A B + A B C
    	

Scott F. Kaplan
Last modified: Thu Feb 9 08:52:46 EST 2006