Digital Logic Circuit
description
Transcript of Digital Logic Circuit
![Page 1: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/1.jpg)
5.5 LOGIC CIRCUIT
![Page 2: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/2.jpg)
LOGIC SYSTEMS
• System performs calculation or makes decisions • A logical operation on one or more logic inputs
and produces a single logic output to make decision.
• Using electronic component that can conduct electricity based on a rule either analog or digital.
• Primarily implement using diodes or transistor acting as electronic switch
![Page 3: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/3.jpg)
POSITIVE AND NEGATIVE LOGIC
![Page 4: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/4.jpg)
OR GATE
X
X = A + B
A B X0 0 00 1 11 0 11 1 1
IF GOT 1 = RESULT MUST BE 1
![Page 5: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/5.jpg)
AND GATE
X = A.B
A B X0 0 00 1 01 0 01 1 1
IF GOT 0 = RESULT MUST BE 0
![Page 6: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/6.jpg)
NOT GATE
A X0 11 0
![Page 7: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/7.jpg)
NAND GATE
A B X0 0 10 1 11 0 11 1 0
X
![Page 8: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/8.jpg)
NOR GATE
A B X0 0 10 1 01 0 01 1 0
X
![Page 9: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/9.jpg)
EXCLUSIVE OR GATE
A B X0 0 00 1 11 0 11 1 0X
![Page 10: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/10.jpg)
EXCLUSIVE OR GATE
C B A X0 0 0 00 0 1 10 1 0 10 1 1 01 0 0 11 0 1 01 1 0 01 1 1 1
Any ODD number of Inputs gives X
X
![Page 11: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/11.jpg)
EXCLUSIVE NOR GATE
A
BX
X
A B X0 0 10 1 01 0 01 1 1
![Page 12: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/12.jpg)
GATE TABLE
A B OR NOR AND NAND EX-OR EX-NOR
NOT A
0 0 0 1 0 1 0 1 10 1 1 0 0 1 1 0 11 0 1 0 0 1 1 0 01 1 1 0 1 0 0 1 0
![Page 13: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/13.jpg)
UNIVERSAL GATE
• NAND gate is universal gate• It can make another gate
NOT GATE
OR GATE
B
AND GATE
![Page 14: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/14.jpg)
IC - INTEGRATED CIRCUIT
Quad 2-input AND Gate 7408
![Page 15: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/15.jpg)
ADDERS
• An adder or summer is a digital circuit that performs addition of numbers.
• For new processor, adder are use to calculate addresses, table indices (database).
• The most common adders operate on binary numbers
![Page 16: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/16.jpg)
HALF ADDER CIRCUIT
• Required 2 input and provide 2 output• Combination of an exclusive OR and an AND
gate
A B SUM CARRY0 0 0 00 1 1 01 0 1 01 1 0 1
SUM = A BCARRY = A . B
![Page 17: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/17.jpg)
FULL ADDER CIRCUIT
• Required 3 input provide 2 output• Combination of 2 half adder and OR gate.
A B Cin Cout S0 0 0 0 01 0 0 0 10 1 0 0 11 1 0 1 00 0 1 0 11 0 1 1 00 1 1 1 01 1 1 1 1
INPUTS OUTPUTS
![Page 18: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/18.jpg)
AIRCRAFT LOGIC CIRCUIT
• LANDING GEAR WARNING CIRCUIT
![Page 19: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/19.jpg)
AIRCRAFT LOGIC CIRCUIT
• FLIGHT DIRECTOR GYRO FLAG - drop when gyro system malfunction either loss of vacuum or electrical signal
Error Flag
![Page 20: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/20.jpg)
GYRO FLAG SYSTEM
![Page 21: Digital Logic Circuit](https://reader030.fdocuments.us/reader030/viewer/2022020201/568c4d391a28ab4916a321de/html5/thumbnails/21.jpg)
SERVO ALTIMETER OFF FLAG• Correct operating when sin outputs (‘0’) and the cos
outputs (‘1’).• When total output is 1, it will energising the OFF Flag
coil, removing the flag from view.