Determine the performance of the circuits, Electrical Engineering

Many circuits, particularly amplifiers, use negative feedback (nfb) in order to function reliably. The nfb changes the performance of the circuit to which it is applied, in most cases to the advantage of the user.  It is important to understand these effects and establish their validity.

It is also important to realize that as the phase of the output changes, the feedback which is initially negative, must eventually become positive. When this happens, unless certain design margins are met, the circuit will become unstable.

Use the reference texts to deduce an expression for the voltage gain of an amplifier.  This may be done for a voltage series, current series, voltage shunt or current shunt circuit.

Complete the questions below:

1. A non-inverting amplifier has an open loop gain of 120 000, an input impedance of 10 kΩ, an output impedance of 100 Ω and the desired closed loop gain is 100.

The signal source provides a 20 mV signal through an output impedance of 500Ω.  The load resistance is 100Ω

Determine:

a)    the approximate feedback fraction

b)    The modified closed loop gain.

c)    The output voltage.

d)    The modified input impedance

e)    The modified output impedance

f)     The voltage across the load

2. If the open loop gain of an amplifier is 100 ±12 dB and the desired closed loop gain is 60 dB determine:

a)    the approximate feedback fraction

Then use this value to determine

b)    The maximum and minimum arithmetic gains

c)    The maximum and minimum gains expressed as dB

Note Av dB  = 20 log(arithmetic Av)

3.  A transistor amplifier has an open loop gain of 500 and low and high corner frequencies of 1 kHz and 15 kHz respectively. If the closed loop gain is 25 determine the new corner frequencies and the % increase in bandwidth.

Posted Date: 2/18/2013 7:28:06 AM | Location : United States







Related Discussions:- Determine the performance of the circuits, Assignment Help, Ask Question on Determine the performance of the circuits, Get Answer, Expert's Help, Determine the performance of the circuits Discussions

Write discussion on Determine the performance of the circuits
Your posts are moderated
Related Questions
Ask questertion #Minimum 100 words accepted#

what do we mean when we say that an equation is dimensionally correct?

BLOCK DIAGRAM OF DIGITAL CONTROL OF ELECTRIC DRIVES

DAD Double Add Instruction The contents of register  R P are added  to the  contents  of HL register pair  and results of addition is stored  in HL register pair. R P   may b

The one line diagram of a simple power system is shown below.  The data of the system are given in the table below.  (a) Draw the impedance diagram of the system and mark all im

what is quality factor in term circuit analysis

Differentiate between Motorola processors and INTEL processors. Comparison between Motorola processors and INTEL processors: AMD/Intel processors are actually about similar t

Q. For the circuit of Figure, determine and sketch i L (t) and vC(t) for inductance values of (a)3/4 H, (b) 2/3 H, and (c) 3/17 H. Note that the inductance values are chosen her

Magnetic materials

Problem : a) What is the definition of Electromagnetic Compatibility (EMC) according to the International Electrotechnical Commission (IEC) and why is it gaining increasing imp