Topics

• Decoders
• Multiplexers
• Half-adders
• Full-adders
• Ripple-carry addition
• Carry look-ahead addition

Decoders

Draw the circuit diagram for a 3-selector decoder. How many outputs does it have? How many inputs does it have?

A decoder has 267 outputs. How many input bits does it have?

Multiplexers

What are multiplexers used for?

Draw the circuit diagram for a 2-bit multiplexer. HOw many outputs does it have? How many inputs does it have?

A 9-input MUX has ____ outputs and ____ select lines.

What are the select lines for a mux? Where do they come from?

Half-adders

How many inputs does a half-adder have? How many outputs does it have?

What is the boolean expression for each of the half-adder's outputs?

Full-adders

How many inputs does a full-adder have? How many outputs does it have?

What is the boolean expression for each of the full-adder's outputs?

Ripple-carry addition

What is ripple-carry addition? Why is it used?

Draw the circuit diagram for ripple-carry addition.

Carry look-ahead addition

What is carry look-ahead addition? WHy is it used?