Question

3. (2 points) The best way to describe the voltage transfer characteristic of a rectifier half-wave diode (not ideal) is to say that approximately (neglecting the avalanche region) #0 Three linear segments b) Two Inear segments c) Two linear segments whose slopes are: 0 and greater than 1, respectively. d) 3 line segments whose slopes are: less than-1, 0 and greater than 1 e) Two linear segments whose slopes are: 0, and less than 1, respectively Two linear segments whose slopes are: less than-1 and greater than 1, respectively. 9) 3 line segments whose slopes are: greater than-1, 0 and less than 1, h) Two linear segments whose slopes are: 0 and 1, respectively. Two linear segments whose slopes are O and-1, respectively Case Respense 4.(1 point) What are the characteristics of an ideall voltage amplifier? b) R늙. 0 Ω. Rat-O ฉ. AT,..VIV Case 5. (1 point) The voltage gain of an emitter follower is best descnibed as a) 1 c)-1 の。 0 0 gain 9) c-1 h) 0 <gain.*

Answer 1

PROBLEM - 4) It can be easily understood that an ideal voltage amplifier can be imagined as a voltage source and a voltage sensor. This is because a voltage amplifier takes input as a voltage and produces output also as a voltage. So at the input side, it acts as a device which senses voltage or we can say as a voltmeter. and we know a voltmeter has an infinite resistance thus this ideal voltage amplifier will also have an infinite input impedance. Now talking about the output, this voltage amplifier gives output as a voltage, so it can be imagined as a voltage source and we know that a voltage source has zero input impedance thus this ideal voltage amplifier will have a zero output impedance. Since amplifier by the definition means it will provide a gain, therefore it cannot have a 0 gain rather will have an infinite gain. Option (F).

A practical half wave rectifier with a diode and its equivalent DC model is represented below: For fig II applying KVL we'll get: v_out = V_in - V d/(rd + R_L) RL = V_in (RL/rd + RL) - r d R L + R_L Hence, it is the equation of line y = mx + c. But the diode, will not be ON until the v_in > vd hence VTC appears as. Thus, option (c) is correct. PROBLEM - 4) It can be easily understood that an ideal voltage amplifier can be imagined as a voltage source and a voltage sensor. This is because a voltage amplifier takes input as a voltage and produces output also as a voltage. So at the input side, it acts as a device which senses voltage or we can say as a voltmeter. and we know a voltmeter has an infinite resistance thus this ideal voltage amplifier will also have an infinite input impedance.

PROBLEM - 5) An emitter follower is also known as a voltage follower or a common collector configuration amplifier. As we know a voltage follower means whatever will be the input it will be just passed to the output and therefore this emitter follower has a gain equal to 1. Option (A).