synonyms: operational amplifiers, op-amps

A part of a circuit used to amplify the voltage coming in. Utilizes a small voltage difference between its inputs to create a large voltage in its output.

Operates on gain - a multiplier for input voltage difference.

Usually we use a feedback loop connecting Vout to the inverting feedback loop to set them to being equal. Then any change in the not inverting input will change Vout accordingly.

Such a small difference between the inputs leads to the following:

High input impedence | Low output impedence

Op amp questions:

Rules:

  1. Essentially no current flows in or out of the inputs
  2. Op amp tries to keep the voltage of the inputs the same (only applies when we use a feedback loop)
  3. HUGE gain

Inverting amplifier

Voltage source going into the negative terminal.

Non-inverting amplifier

Voltage source is going into the positive terminal.