How to create a circuit that outputs only 1, regardless of inputs

Question

So this is the truth table:

In_1  In_2  In_3  Out
0      0    0      1
0      0    1      1
0      1    0      1
0      1    1      1
1      0    0      1
1      0    1      1
1      1    0      1
1      1    1      1

How do I create a circuit that matches this truth table?

Here is what I have tried, but this did not work:

Please help would be appreciated.

score 1 · Accepted Answer · answered Dec 18 '22 at 15:44

1

You just need to connect the output to a constant logic 1, which is usually just the power supply voltage. This is a trivial logic function and requires no gates to implement.

answered Dec 18 '22 at 15:44

Elliot Alderson

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Thank you very much for your reply. so I just have to connect the inputs directly to the output? – randomUser786 Dec 18 '22 at 16:12
No, you can completely ignore the inputs...you don't need to connect them to anything. The output is always the same, and is always 1, regardless of the input values. So, just connect the "output" signal to logic 1 (the power supply) and you are done. – Elliot Alderson Dec 18 '22 at 18:44

score 0 · Answer 2 · answered Dec 18 '22 at 13:55

The solution is to apply Kmap. We will be ending up with an equation that will be similar to

but this is not the reduced form. If we try to reduce this equation we will end up with 1.

Check this tool for better understanding. https://www.boolean-algebra.com/kmap/

How to create a circuit that outputs only 1, regardless of inputs

2 Answers2