1. Operational Amplifiers
Op-Amps
Operational Amplifiers

2. What is an Op-amp ?
An op-amp is a type of amplifier – an operational amplifier.
It takes in one or more voltages ( V1 and V2 ) and processes them, giving out another voltage ( Vout ).
Depending on how it is connected up, the op-amp seems to carry out mathematical operations such as addition, subtraction etc.

3. The Op-Amp Symbol
+Vs
Inverting input -
Output
Non-inverting input +
-Vs
The Op-Amp needs a power supply to make it work. This is represented by Vs.
The power supply connections are often missed out in diagrams.

4. Power Supplies for Op-Amps
The power supplies used with Op-Amps are a bit unusual. They are set up to have a positive terminal and a negative terminal and a zero volts terminal between the two.
The zero volts terminal acts as a reference voltage when making measurements.