TABLE OF CONTENTS Objective: The study of combinational circuits is divided into two parts. The first part, called combinational logic circuits, deals with logical functions and was the subject of Chapter 11. The second part, called Combinational arithmetic circuits, deals with arithmetic functions and is the subject of this chapter. This type of design will be further illustrated using VHDL in Chapter 21.
Chapter Contents
| 12.1 | Arithmetic versus Logic Circuits |
| 12.2 | Basic Adders |
| 12.3 | Fast Adders |
| 12.4 | Bit-Serial Adder |
| 12.5 | Signed Adders/Subtracters |
| 12.6 | Incrementer, Decrementer, and Two's Complementer |
| 12.7 | Comparators |
| 12.8 | Arithmetic-Logic Unit |
| 12.9 | Multipliers |
| 12.10 | Dividers |
| 12.11 | Exercises |
| 12.12 | Exercises with VHDL |
| 12.13 | Exercises with SPICE |
The study of combinational circuits is divided into two parts depending on the type of function that the circuit implements.
The first part, called combinational logic circuits, was seen in the previous chapter. As the name indicates, such circuits implement logical functions, like AND, OR, XOR, multiplexers, address encoders/decoders, parity detectors, barrel shifters, etc.
The second part is called Combinational arithmetic circuits and is discussed in this chapter. Again, as the name says, such circuits implement arithmetic functions, like adders, subtracters, multipliers, and dividers. A wide range of circuits will be presented along with discussions on signed systems and application alternatives.
Several adder architectures will be presented and discussed in this chapter. The discussion starts with a review of the fundamental single-bit unit known as full-adder, followed...
