# Basic Electronics Ninth Edition Basic Electronics Ninth Edition ©2002 The McGraw-Hill Companies Grob Schultz.

## Presentation on theme: "Basic Electronics Ninth Edition Basic Electronics Ninth Edition ©2002 The McGraw-Hill Companies Grob Schultz."— Presentation transcript:

Basic Electronics Ninth Edition Basic Electronics Ninth Edition ©2002 The McGraw-Hill Companies Grob Schultz

Basic Electronics Ninth Edition Basic Electronics Ninth Edition ©2003 The McGraw-Hill Companies 31 CHAPTER Digital Electronics

Topics Covered in Chapter 31 Binary and Decimal Numbers Decimal to Binary Conversion Hexadecimal Numbers Binary Coded Decimal System The ASCII Code Logic Gates, Symbols, and Truth Tables

Boolean Algebra DeMorgan's Theorem Treating Unused Inputs TTL and CMOS Circuits Active HIGH/Active LOW Terminology Topics Covered in Chapter 31 (continued)

Topics Covered in Chapter 31 (continued) Combinational Logic Circuits Binary Adders Flip-Flops, Counters, and Registers New Logic Symbols Troubleshooting Digital Circuits

Number Systems Decimal Base 10; digits are 0 through 9 Most commonly used by humans Binary Base 2; digits are 0 and 1 Most commonly used by computers Hexadecimal Base 16; digits are 0 through F BCD Binary Coded Decimal

DecimalBinaryHex 000 111 2102 3113 41004 51015 61106 71117 810008 910019 101010A 111011B 121100C 131101D 141110E 151111F Decimal (base 10) 134 10 = 4 x1 + 3x10 + 1x100 = 134 10 Different Base Numbers Binary (base 2) 10000110 2 = 0x1 + 1x2 + 1x4 +0x8 + 0x16 + 0x32 +0x64 + 1 x 128 = 134 10 Hex (base 16) 86 16 = 6x1 + 8x16 = 134 10

Logic Gates AND gate OR gate XOR gate NAND gate NOR gate XNOR gate Inverter ( NOT gate)

Logic Inverter A logic inverter switches the state of its input. Changes 0 to 1 Changes 1 to 0 Logic inverters can invert the outputs of other logic gates. Change an AND gate to a NAND gate Change an OR gate to a NOR gate Change an XOR gate to an XNOR gate A10A10 B01B01 A B

AND / NAND Logic Functions AND function NAND function B0011B0011 C0101C0101 A0001A0001 B0011B0011 C0101C0101 A1110A1110 A B C A B C

OR / NOR Logic Functions OR function NOR function B0011B0011 C0101C0101 A0111A0111 B0011B0011 C0101C0101 A1000A1000 A B C A B C

XOR / XNOR Logic Functions XOR function XNOR function B0011B0011 C0101C0101 A0110A0110 B0011B0011 C0101C0101 A1001A1001 A B C A B C A = B+C

DeMorgans Theorems X A B X A B A + B = A B = A B = A + B A B X A B = X

Combinational Logic Circuits ABCX 0000 0010 0100 0110 1000 1011 1101 1111 A B C X X = A(B + C)

X = ABC + ABC + ABC + ABC ABCX 0000 0011 0100 0110 1000 1011 1101 1111 Truth Table Boolean Expression Simplify X = BC(A + A) + AB(C + C) X = BC + AB Factor: 1 { 1 {

Flip-Flop Circuits Flip-flop circuits are digital devices that hold a 0 or 1 output until some event triggers them to the opposite output. They are commonly used for storing digital data on a temporary basis.

Major Types of Flip-Flop Circuits Set/reset (SR) flip-flops. Q Q S R Q Q D CLK Q Q J K J-K flip flops. D-type flip-flops.

Q Q S R SR Flip-Flop with Active HIGH Inputs Q Q S R Time Q Q S R

Q Q R S SR Flip-Flop with Active LOW Inputs Q Q S R Time +V CC Q Q S R

Q R CLK S Time Clocked SR Flip-Flop Q Q S R CLK

Q Q D Negative-Edge Triggered D Flip-Flop Q CLK D Time CLK

Q Q J Negative-Edge Triggered JK Flip-Flop Q CLK J Time CLK K K ModeJKQ Inhibit00Q Set101 Reset010 Toggle11Q

Q Q J CLK K Binary Counter 1 1 Q Q J K 1 1 Q Q J K 1 1 Q Q J K 1 1 Q0Q0 Q1Q1 Q2Q2 Q3Q3 Q2Q2 CLK Q0Q0 Q1Q1 Q3Q3