电子科技大学：《VHDL语言与数字集成电路设计》数字逻辑1-1

Digital Design Pinciples and practices Teacher:张鹰 Email: zhangyin Questc. edu

Digital Design —Pinciples and Practices Teacher：张鹰 Email: zhangyin@uestc.edu

Chapter 1: Introduction From Analog to Digital Digital circuits and devices Design for Ic The target of the text The arrangement of the text

Chapter 1: Introduction From Analog to Digital Digital circuits and devices Design for IC The target of the text The arrangement of the text

From Analog to Digital Sampling--hold-change to digital 1111000 110110l10l1011010000 110 100 011 010 000 2 t3 t4 ts t6 t t t2 t3 t4 t5 Sampling in discrete time Record in limited words in binary system

From Analog to Digital Sampling—hold—change to digital Sampling in discrete time Record in limited words in binary system

Digital circuit Digital signal value: the string of i and o the power source or High voltage 0: the ground or Low voltage; A node in circuit can get 1 or o through switches from the power or the ground

Digital circuit Digital signal value: the string of 1 and 0 1 : the power source or High voltage; 0 : the ground or Low voltage; A node in circuit can get 1 or 0 through switches from the power or the ground;

Digital circuit A node in circuit can get voltage(1 or 0)through switches from the power or the ground; Vcc k=0 Vo The states of the switch Gnd

Digital circuit A node in circuit can get voltage (1 or 0) through switches from the power or the ground; The states of the switch

Basic logic in digital design ANd gate X X2 y diagram Vcc y=xl. x2 equation X2 X1 x2 00 Truth table 01 10 000 Gnd Three forms of a logic

Basic logic in digital design AND gate y = x1 x2 diagram equation Truth table Three forms of a logic

Basic devices in digital circuit OR gate X2 cc y=xl+x2 x1 x2 X1×2|y 000 0 10 Gnd

Basic devices in digital circuit OR gate y = x1+ x2

Basic devices in digital circuit noT gate (inverter, INV) Vcc X X01 Gnd 0

Basic devices in digital circuit NOT gate (inverter , INV) y = x 

Other basic devices NAND NOR XOR a b bof b2-f (ab)f=(a+b)f=a⊕b n bf a00 0 a00 0 000 0 10 110 000 0 10

Other Basic devices NAND f = (ab)' NOR XOR f = (a +b)' f = a b

Two classes of digital circuit Combinational circuit Sequential circuit combinational Hy x sequential Y Y=F(X Y-F(X, Q) the output depend the output depend on only on current inputs and states, with inputs, no memory memory by feedback

Two classes of digital circuit the output depend only on current inputs, no memory the output depend on inputs and states, with memory by feedback Combinational circuit Sequential circuit