Hi guys,

i am working on a very simple circuit that take in a 3 bit unsigned value ABC and output a 5 bit binary number S0-S4 that is 5 times of the input value.

This my truth table :

SOP expressions i got are :

S4 = A

S3 = B + A.C

S2 = A.C' + A'.C = A XOR C

S1 = B

S0 = C

I have a 74LS20 NAND gate and a 74LS83 4-bit Parallel adder only, how do i actually start connecting this circuit?

i am working on a very simple circuit that take in a 3 bit unsigned value ABC and output a 5 bit binary number S0-S4 that is 5 times of the input value.

This my truth table :

Rich (BB code):

```
A B C S4 S3 S2 S1 S0 V
0 0 0 0 0 0 0 0 1
0 0 1 0 0 1 0 1 1
0 1 0 0 1 0 1 0 1
0 1 1 0 1 1 1 1 1
1 0 0 1 0 1 0 0 1
1 0 1 1 1 0 0 1 1
1 1 0 1 1 1 1 0 1
1 1 1 X X X X X 0 (Invalid)
```

S4 = A

S3 = B + A.C

S2 = A.C' + A'.C = A XOR C

S1 = B

S0 = C

I have a 74LS20 NAND gate and a 74LS83 4-bit Parallel adder only, how do i actually start connecting this circuit?

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