Unit 3 : Logic Gates Flashcards
What devices control the movement of electrons, and consequently, electricity?
- Transistors
What is computer built up?
- Integrated Circuits ( ICs )
List out the example for Integrated Circults ( ICs )
- CPU
- Bus Interface
- Memory Management Unit
- It was made up of transistors, resistors, capacitors and other electronic components
What is the primary components of Integrated Circuits ( ICs )
- Transistors
How many pins are there in the Transitors ?
- 3
* 1st Pin ( Inlet )
2nd Pin ( Controler )
3rd Pin ( Outlet )
2nd Pin decides to let the electicity flow through 3rd Pin
What does resistors do?
- To resist the current of the electrity to control the electrity flowing to the devices
What does capacitor do?
- Stores small amount of electrical energy in a circult
Does 0 means no electricity flows through the circut?
- No, 0 has electricity, it was just a signal
List out all the logic gates ( 7 )
- Not Gate
- Or Gate
- And Gate ( Carry )
- Exclusive-OR Gate ( XOR ) ( Sum )
- NAND Gate
- NOR Gate
What will Not operators return?
- Result True if single input value is False
- x = A
- Return the opposite value ( 0 -> 1 , 1 -> 0 )
What is Truth Table do in logic gates
- Specifies results for all possible input combination
What will Or operators return?
- Returns True if any input operands are true ( 0 + 0 = False ( 0 ) , 1 + 0 = True ( 1 ) , 0 + 1 = True , 1 + 1 = 1 ( True ) )
* x = A + B
* x will only be true when A or B is true
What will Inclusive Or operators return?
- Result True is both input operands are true ( 0 * 0 = False ( 0 ) , 1 * 1 = 1 ( True ) , 1 * 0 = False , 0 * 1 = False )
- x = A * B
= A . B
= AB - Returns true if both input is true, one false will return in false
What does Exclusive Or ( XOR ) operators return?
- Result True if either A or B is True but not both ( 0 * 0 = False ( 0 ) , 1 * 1 = 0 ( False ) , 0 * 1 = True ( 1 ) )
- A xor B = ( A + B ) * ( A * B ) ‘
- A xor B = ( A * ( B ) ‘ ) + ( B * ( A ) ‘ )
’ means NOT
* It can be derived from OR, AND and NOT
* Can also named it the hating operator, which means that returns false if both value is the same
What is VLSI stands for?
- Very Large-Scale Integration
What are the 3 fundamental operations?
- AND
- OR
- NOT
What is boolean logic?
- Rules for handling Boolean constants and variables
What operator does NAND gate combine?
- And Gate
- Not Gate
What operator does NOR gate combine?
- Not Gate
- Or Gate
What is basic for computer design?
- Boolean Algebra
What is combinatorial logic?
- Combinatorial logic is a type of digital logic where the output depends solely on the present inputs, with no memory of previous operations
List out of some examples for some of the things that uses combinatorial logic ( 4 )
- Logic gates (AND, OR, NOT, XOR)
- Multiplexers
- Decoders
- Arithmetic circuits like adders and subtractor
What is sequantial logic?
- A type of digital logic where the output depends on both the current inputs and the results of previous operations, typically using memory elements to store past state
List out of some examples for some of the things that uses sequential logic ( 1 )
- Counter
What is gates or logical gates
- Integrated circults constructured from transistor switched and other electronic components
What are the main use for multiplexers?
- Mainly used to increase the amount of data that can be sent over the network within a certain amount of time and bandwidth
What does multiplexers also called as?
- Data selector
What is multiplexers
- A device that selects one of several analog or digital input signals and forwards the selected input into a single line
What is a half-adder circult?
- It is a combinational circuit that adds two single-bit binary numbers and produces a sum and a carry
What does Half-Adder Output?
- Sum ( XOR Gate )
- Carry ( AND Gate )
What is a Full-Adder Circult ?
- It is a combinational circuit that adds three single-bit binary numbers: two regular bits and an additional carry bit from a previous stage
- It will also outputs a sum and carry
Full-Adder has how many value?
- 3
A , B and C ( Carry bit )
Why XOR works as sum?
- Because the calculation was like addition on binary digits
A B C
0 0 0
1 0 1
0 1 1
1 1 0
0 + 0 = 0
1 + 0 = 1
0 + 1 = 1
1 + 1 = 10 ( But C shows only 1 digits so it was 0 )
Why AND works as a carry?
- Carry is the carry over value ( 1 + 1 = 10 , 1 is carried over to the second digit )
A B C
0 0 0
1 0 0
0 1 0
1 1 1
0 + 0 = 0
1 + 0 = 0
0 + 1 = 0
1 + 1 = 10 ( This has a carry value, so it has 1)
What is the table name for output for all combinations of input and previous states?
- Truth Table
What is the basic memory element for logic circuits?
- Flip-Flop
