Electronics - Logic Gates - Discussion

AND gate truth table

0*0=0
0*1=0
1*0=0
1*1=1

AND Gate : in case of AND if both the inputs are high then output is high means "1",otherwise it is low "zero".

AND gate always works as a input multiplier & it is clear that any value multiply with 0 always gives 0 as result.

0*0 = 0
0*1 = 0
1*0 = 0
1*1 = 1

Clearly show that the low output at low input.

OR gate inputs have A and B and its output is Q.

A B Q(A+B)
0 0 0
0 1 1
1 0 1
1 1 1

Here, for OR gate, output is not low when the inputs are zero.

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NOT gate reflects an opposite result.
That is:- when input is 0, output is 1.
When input is 1, output is 0.
Thus, it does not reflects that output is low.
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NAND gate inputs are A and B and its output is Q.

A B Q( oomplement of A*B)
0 0 1
0 1 1
1 0 1
1 1 1

Here we have seen that, when any of the input is 0, output is high, ie. 1.
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AND gate:- Inputs are A and B and Output is Q.

A B Q(A*B)
0 0 0
0 1 0
1 0 0
1 1 1

For AND gate, we have seen that, whenever there is 0 as an input, we are getting the l ow value that is:- zero(0).

Hence answer is AND gate.

We know that the AND gate will working on the principle of multiplication. The truth table of AND gate is shown below,

A B Y
0 0 0
0 1 0
1 0 0
1 1 1

In truth table A & B are input and Y is output. Consider the truth table in multiplication principle. If any one of the input is zero,the AND gate produces the output low(zero). If two inputs is one(1 1)then the AND gate produces the output high(1).

Simply keep in mind, AND is always multiplication.

If any inputs is low then output must be low, both input is high then output must be high. (because the function of AND GATE is multiplication).

Let us consider two inputs of a gate A & B.

If A=0 & B=0 the o/p of AND gate OR gate are [0].

But A=1 & B=0 the o/p of AND gate is [0] and A=0 & B=1 here also And gate o/p is 0.

Ans:- Option C.

Which gates are universal gate?