CIE A Level Physics (9702) 2019-2021

Revision Notes

24.1.2 Negative Feedback

Negative Feedback

  • Negative feedback of an op-amp is defined as:

The process of taking some, or all, of its output and adding it to the input and is out of phase with the input

  • This is to produce self-stabilising systems
  • To make the feedback negative, it is fed to the negative (inverting input) terminal of an op-amp
    • The effect produced a closed-loop circuit results in ‘closed-loop’ gain
  • The effects of negative feedback on the gain on an op-amp are:
    • Reduced gain
    • Increased bandwidth or less distortion
    • Increase operating stability
  • If some of the output voltage is fed back to the inverting input (V) then gain A can be altered to a lower value

Author: Katie

Katie has always been passionate about the sciences, and completed a degree in Astrophysics at Sheffield University. She decided that she wanted to inspire other young people, so moved to Bristol to complete a PGCE in Secondary Science. She particularly loves creating fun and absorbing materials to help students achieve their exam potential.

Join Save My Exams

Download all our Revision Notes as PDFs

Try a Free Sample of our revision notes as a printable PDF.

Join Now
Go to Top