CMOS Analog Integrated Circuits

A

Logic Building Blocks

CONTENTS

A.1    Boolean algebra

A.1.1    Basic operations

A.1.2    Exclusive-OR and equivalence operations

A.2    Combinational logic circuits

A.2.1    Basic gates

A.2.2    CMOS implementation

A.3    Sequential logic circuits

A.3.1    Asynchronous SR latch

A.3.2    Asynchronous $\overline{S}$ $\overline{R}$ latch

A.3.3    D latch

A.3.4    D flip-flops

A.3.5    CMOS implementation

A.4    Bibliography

A.1    Boolean algebra

Boolean algebra is used to describe the relations between inputs and outputs of a digital circuit. The input and output signals are considered to be Boolean variables (X, Y, Z) whose values are either 0 (logic low level) or 1 (logic high level).

A.1.1    Basic operations

NOT	AND	OR
$\overline{0}$=1	0·X = 0	0 + X = X
$\overline{1}$=0	1·