13.3.3 Understanding feedback and stability

• What is feedback in amplifiers?

  Re-injecting output into input
• Negative feedback in amplifiers reduces the overall gain.


  True
• Positive feedback in amplifiers can lead to potential oscillation
• What are the two types of feedback in amplifiers?

  Positive and negative
• Negative feedback in amplifiers improves signal accuracy
• Negative feedback reduces the overall gain of an amplifier.


  True
• Negative feedback in amplifiers increases the signal bandwidth
• What is the effect of positive feedback on amplifier stability?

  Decreases stability
• Positive feedback reinforces the original signal, leading to potential instability
• Why is negative feedback essential for achieving stable op-amp performance?

  Reduces oscillation risk
• Negative feedback reduces overall gain
• Match the feature with its effect in stability with and without feedback:

  Gain ↔️ Lower with negative feedback

  Oscillation Risk ↔️ Higher without feedback

  Accuracy ↔️ Improved with negative feedback

  Bandwidth ↔️ Wider with negative feedback
• What are the two types of feedback in amplifiers?

  Positive and negative
• Negative feedback reduces gain but enhances stability and accuracy.

  True
• Order the effects of negative feedback on amplifier features:

  1️⃣ Lowers overall gain

  2️⃣ Increases bandwidth

  3️⃣ Improves stability

  4️⃣ Reduces distortion

  5️⃣ Increases input impedance
• Positive feedback often makes amplifiers unstable.

  True
• What are compensation techniques used for in op-amps?

  To stabilize them
• Positive feedback in amplifiers increases the signal gain
• Why is negative feedback crucial for stabilizing amplifiers?

  Reduces oscillation risk
• Negative feedback in amplifiers reduces noise and distortion.


  True
• Match the feedback type with its effect on stability:

  Positive feedback ↔️ Decreases stability

  Negative feedback ↔️ Increases stability
• What is a primary characteristic of positive feedback in amplifiers?

  Enhances signal amplification
• What are the beneficial effects of negative feedback in amplifiers?

  Improves stability and reduces distortion
• Negative feedback decreases the output impedance of an amplifier.


  True
• Stability in op-amps refers to their ability to maintain a consistent output without oscillating.


  True
• Negative feedback in op-amps results in a lower but adjustable signal gain
• Stability in op-amps refers to their ability to maintain a consistent output without oscillating.


  True
• Negative feedback minimizes the risk of oscillations
• Positive feedback increases gain but decreases stability
• Match the feedback type with its effect on gain and stability:

  Positive feedback ↔️ Increases gain, decreases stability

  Negative feedback ↔️ Reduces gain, increases stability
• Negative feedback decreases output impedance
• Negative feedback reduces gain and minimizes oscillation risk
• Match the compensation technique with its description:

  Dominant Pole Compensation ↔️ Reduces gain at higher frequencies

  Lag Compensation ↔️ Improves low-frequency gain

  Lead Compensation ↔️ Enhances stability at high frequencies