problem 1:

a) A combinational circuit produces the binary sum of two 2-bit numbers, x1 x0 & y1 y0. The outputs are C, S₁ & S_o provide a truth table of the combinational circuit.
 
b) Design a converter with 3 inputs & 1 output. The output is equal to logic – 1 when the binary value of the input is <3. The output is logic – O otherwise.
 
c) Implement a full – adder with two 4 x 1 multiplexers
 
problem 2:

a) Construct a 16 x 1 multiplexer with two 8 x 1 & one 2 x 1 multiplexer
 
b) Implement the following Boolean function with an 8 x 1 multiplier

F (A,B,C,D) = ∑ (0,3,5,6,8,9,14,15)
 
c) A combinational circuit is defined by the following 3 Boolean functions. Design the circuit with a decoder and external gates - F₁ = x’y’z’ + xz, F2 = xy’z’ + x’y, F3 = x’y’z + xy.
 
problem 3:

a) Design a 4 input priority encoder with input Do having the highest priority and input D₃ the lowest priority.
 
b) Implement a 3 – bit Odd parity generator using XOR gates.
 
problem 4:

a) Realise a 1 x 4 Demux by using 1 x 2 Demux.
 
b) Differentiate multiplexer and demultiplexer with exs
 
c) Design a combinational circuit with 4 inputs & 4 outputs. The output generates the 2’s complement of the input binary number