Contents
ix
Review Questions
67
Problems
68
Further Reading
68
4 Logic Gates and Related Devices
69
4.1 Positive and Negative Logic
69
4.2 Truth Table
70
4.3 Logic Gates
71
4.3.1 OR Gate
71
4.3.2 AND Gate
73
4.3.3 NOT Gate
75
4.3.4 EXCLUSIVE-OR Gate
76
4.3.5 NAND Gate
79
4.3.6 NOR Gate
79
4.3.7 EXCLUSIVE-NOR Gate
80
4.3.8 INHIBIT Gate
82
4.4 Universal Gates
85
4.5 Gates with Open Collector/Drain Outputs
85
4.6 Tristate Logic Gates
87
4.7 AND-OR-INVERT Gates
87
4.8 Schmitt Gates
88
4.9 Special Output Gates
91
4.10 Fan-Out of Logic Gates
95
4.11 Buffers and Transceivers
98
4.12 IEEE/ANSI Standard Symbols
100
4.12.1 IEEE/ANSI Standards – Salient Features
100
4.12.2 ANSI Symbols for Logic Gate ICs
101
4.13 Some Common Applications of Logic Gates
102
4.13.1 OR Gate
103
4.13.2 AND Gate
104
4.13.3 EX-OR/EX-NOR Gate
104
4.13.4 Inverter
105
4.14 Application-Relevant Information
107
Review Questions
109
Problems
110
Further Reading
114
5 Logic Families
115
5.1 Logic Families – Significance and Types
115
5.1.1 Significance
115
5.1.2 Types of Logic Family
116
5.2 Characteristic Parameters
118
5.3 Transistor Transistor Logic (TTL)
124
5.3.1 Standard TTL
125
5.3.2 Other Logic Gates in Standard TTL
127
5.3.3 Low-Power TTL
133
5.3.4 High-Power TTL (74H/54H)
134
5.3.5 Schottky TTL (74S/54S)
135