# Digital Electronics Flashcards

Analogue signals take…

**Continuous** values

Digital signals take…

Restricted rages of amplitude

Binary signals are ____ signals that take only _ ____

Binary signlas are digital signlas that take only 2 ranges

What does an anolog and digital signal graph look like?

Why digital?

__Reliability__

- Anologue circuits are more vulnerable to noise
- Digital circuits can tolerate some levels of noise

Base 2 means?

We can only use 0 and 1

How would you write 11010.1 in binary?

How do you convet decimal to binary?

The hexadecimal number system represents…

A larger range of values with one digit

Basic Boolean operations are…

**AND, OR** and **NOT**

If the variable doesn’t have the value 0, it must have…

The value 1 and vice versa

Symbols like ____ to represent Boolean ____

Symbols like **A, B etc** to represent Boolean variables

What do truth tables do?

Describe how a logic circuit (gate) outputs depend on it’s inputs

What sign is commenly used to represent an **Or** gate?

The plus sign (+)

What does an Or gate look like?

What gate produces an output of 1 ** whenever** when all of the inputs are 1?

An **Or** gate

What does an **And** gate look like?

What is the Boolean expression for an **Or** gate?

z = x + y

What is the Boolean expression for an **And** gate?

z = x . y

What sign is used to commonly represent the **And** gate?

The period (dot) sign .

What gate produces an output of 1 ** only** when all of the inputs are 1

An **And** gate

What is the symbol for a **Not** gate?

What is the Boolean expression for a **Not** gate?

z = ¬x

What sign is commonly used to represent a **Not** gate?

The ¬ sign is commonly used to represent not. Sometimes a bar over the variable is used also

A **Not** gate is a…?

Circuite that inversts - or negates - the input signal

What gate produces an output of 1 whenever the input is 0, and an ouput of 0 when the input is 1

A **Not** gate

What is the symbol for a **Nand** gate?

What is the Boolean expression for a **Nand** gate?

z = ¬ ( x . y )

Sometimes you will see this written in the notation that has a bar over the top

What gate produces an output of 1 only when any one of the inputs are 0?

A **Nand** gate

A **Nand** gate is…

the logical not of the output of an **And** gate

What is the symbol of a **Nor** gate?

What is the Boolean expression of a **Nor** gate?

z = ¬ ( x + y )

What gate has an output of 0 whenever any of the inputs are 1?

A **Nor** gate

A **Nor** gate is…

The logical not of the output of an Or gate

What is the symbol for an **Xor** gate?

What is the Boolean expression for an **Xor** gate?