What type of Boolean logic circuit is this?

Question

I need help confirming some hunches. I'm trying to figure out what type of circuit this is:

Any ideas?
Also, I think the logic expression for this is: D = (A AND B) OR (NOT(B) AND C)

Answer 1

There are only two intermediate signals, so it's relatively easy to break down. We'll call the left input to the bottom OR gate X and the right input Y.

I'm going to use some shorthand here - NOT = !, AND = &, OR = |.

X = A & B

Y = !B & C

Those two lead into the OR gate that produces D:

D = (A & B) | (!B & C)

Which is the result you came up with, so you are correct.

One application of this logic circuit is to act as a selector:

• When B is asserted, then A is output on D, and C is ignored.
• When B is de-asserted, then C is output on D, and A is ignored.

Answer 2

Its a 2:1 multiplexer, the select input being B. A and C are inputs, D is the output