Feedback Amplifier - 1

The term (1+Aβ) is called as

• De-sensitivity

• Sensitivity

• Loop Gain

• None

Which of the following is correct with respect to transresistance amplifier?

• Output current is proportional to the signal current

• Output voltage is proportional to the signal current

• Output voltage is proportional to the signal voltage

• Output current is proportional to the signal voltage

When current feedback (negative) is applied to an amplifier, its output impedance....

• is decreased

• is increased

• remains the same

• none of the above

The essential conditions for sustained oscillation are

• |Aβ|=1 & ∠Aβ=0

• |Aβ<1 & ∠Aβ=0

• |Aβ|>1 & ∠Aβ=0

• |Aβ|<1 & ∠Aβ=180^o

The degenerative feedback amplifier overall gain is given by

• A_f = A/(1+Aβ)

• A_f = 1+Aβ

• A_f = A/(1-Aβ)

• A_f = 1-Aβ