Difference between positive and negative feedback

The main key difference between positive and negative feedback loop is that the positive feedback loop amplifies the initiating stimulus moving the system away from its equilibrium whereas the negative feedback loop counteracts the change of the system, maintaining them in a set point. This post gives information about the difference between positive and negative feedback to better understand this topic.

  • Positive feedback is a less frequent mechanism, negative feedback is the more frequent mechanism.
  • Positive feedback is a wide range, negative feedback is narrower range.
  • Positive feedback is less associated with stability, negative feedback is closely associated with stability.
  • The overall phase shift of positive feedback is 0 or 360 degrees while negative feedback overall phase shifts 180 degrees. 
  • Overall gain is increased while using positive feedback, overall gain decreases while using negative feedback.
  • Positive feedback may be enhanced change, negative feedback resists change.
  • Positive feedback exhibits a positive correlation between stimulus product or process, negative feedback exhibits a negative correlation between stimulus and product or process.
  • Positive feedback may be associated with vicious cycles and even death, while negative feedback most often associated with restoring homeostasis.
  • Positive feedback may require external interruption, whereas negative feedback does not require external interruption.
  • while using Positive feedback input and output signal even noise change when increases due to feedback but in negative feedback input and output chances decreases due to feedback.
  • Positive feedback use as an oscillator, negative feedback use as an amplifier.