Question

g Which statement is true about the difference between combinational logic circuits and sequential logic circuits? A) Combinational circuits combine the inputs and the outputs, but sequential circuits combine the outputs only after generating the inputs. B) Combinational circuits are more complicated than sequential circuits. C) Combinational circuits have feedback, but sequential circuits do not. D) If you know the values of the inputs to a combinational circuit, you can tell what the outputs must be, but a sequential circuit can have different outputs for the same set of input values. E) Combinational circuits are edge triggered, but sequential circuits are level sensitive.

Answer 1

Answer:

D.

Explanation:  

In combinational circuits, the current output values are always the same for the same set of input values, regardless the previous values.

We say that combinational circuits have no memory, or that the circuit has no feedback from the outputs.  

For sequential circuits, on the contrary, the current output values are not based in the current input values only, but on the previous output values as well.

So, the fact of having a defined set of input values at a given moment, doesn't guarantee which the output values will be.

We say that sequential circuits have memory, or that they have feedback from the outputs.

Examples of these type of circuits are R-S, J-K, D or T flip-flops.