An ideal OP-AMP is an ideal___________?
(A) Current controlled Current source
(B) Current controlled voltage source
(C) Voltage controlled voltage source
(D) voltage controlled current source
An amplifier without feedback has a voltage gain of 50,input resistance os 1 KΩ & Output resistance of 2.5KΩ.The input resistance of the current-shunt negative feedback amplifier using the above amplifier with a feedback factor of 0.2 is___________?
(A) 1/11KΩ
(B) 1/5KΩ
(C) 5KΩ
(D) 11KΩ
In the differential voltage gain & the common mode voltage gain of a differential amplifier are 48db &2db respectively, then its common mode rejection ratio is__________?
(A) 23dB
(B) 25dB
(C) 46dB
(D) 50dB
Generally, the gain of a transistor amplifier falls at high frequencies due to the___________?
(A) Internal Capacitance of the device
(B) Coupling capacitor at the input
(C) Skin effect
(D) Coupling capacitor at the output
The current gain of a bipolar transistor drops at high frequencies because of____________?
(A) Transistor capacitances
(B) High current effects in the base
(C) Parasitic inductive elements
(D) The early effect
Negative feedback in an amplifier____________?
(A) Reduces gain
(B) Increase frequency &phase distortion
(C) Reduces bandwidth
(D) Increases noise
Class AB operation is often used in power large signal amplifiers in order to_________?
(A) get maximum efficiency
(B) remove even harmonics
(C) overcome a crossover distortion
(D) reducing collector dissipation
An n- channel JFET has IDSS=2mA,and Vp=-4v.Its transconductance gm=in mA/V)for an applied gate to source voltage VGS=-2v is___________?
(A) 0.25
(B) 0.5
(C) 0.75
(D) 1
The effective channel length of a MOSFET in a saturation decreases with increase in___________?
(A) Gate voltage
(B) Drain voltage
(C) Source voltage
(D) Body voltage