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Flashcards in Logic Gates Deck (10)
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1

What are Logic Gates?

They are circuits used to perform logical operations

2

What is a Truth Table?

A Truth Table is a diagram that shows all possible logical inputs and their associated outputs.

3

Name the 6 logic gates.

AND
OR
NOT
XOR
NAND
NOR

4

what does a NOT gate do and what does it look like and how is it represented in an expression?

- The output is the inverse of the input
- Has a triangle and a little circle
- represented by an overbar, Q = ‾A

5

what does a AND gate do and what does it look like and how is it represented in an expression?

- Two or more inputs where the output is true if all inputs are true
- Has a D shape
- represented by a dot, Q = A . B

6

what does an OR gate do and what does it look like and how is it represented in an expression?

- Two or more inputs where the output is true if either or both inputs are true
- Has a crescent shape
- represented by a plus, Q = A + B

7

what does an XOR gate do and what does it look like and how is it represented in an expression?

- Takes two or more inputs where the output is true if one input is exclusively true
- Has a crescent shape with an extra curved line
- represented by a circle with a plus inside, Q = A⊕B

8

what does a NAND gate do and what does it look like and how is it represented in an expression?

- It inverts the output of an AND gate
- Has a D shape and a little circle
- represented by an overbar over A . B

9

what does a NOR gate do and what does it look like and how is it represented in an expression?

- Takes two or more inputs where the output is true when all inputs are false
- Has a crescent shape with a little circle
- represented by an overbar over A + B

10

How do you know how many rows to fill in in a logic table?

Do 2 to the power of the number of inputs
2^2 inputs = 4 rows
2^3 inputs = 8 rows