What is barkhausen criterion, Electrical Engineering

Assignment Help:

Q. What is Barkhausen criterion? Why is the value of Ab kept slightly greater than 1?

The condition |Ab| = 1 is called the Barkhausen criterion. It implies that when |Ab| = 1, there exists an output voltage even in the absence of any externally applied signal. If |Ab| = 1, the feedback voltage is sufficient for producing self sustained oscillations. If Ab = 1 precisely, then after sometime it is found that Ab will either become lower or higher than unity. This is due to the change in the characteristics of the active devices with voltage, temperature or age. If Ab < 1, the removal of input signal source will result in dying out of oscillations. If Ab > 1, then the amplitude of the oscillations will continue to increase until clipping occurs because of saturation and cut-off causing the voltage gain to reduce.

Hence, Ab is kept slightly larger than unity so that any variation in circuit parameters may not cause Ab to become less than unity.


Related Discussions:- What is barkhausen criterion

Circuit with inductive load, Circuit with inductive load  Electromagnet...

Circuit with inductive load  Electromagnetic induction When a conductor is moved across a magnetic field so as to cut by the lines of force (or flux, an electromotive force

Impact of diversity, Both GSM and DECT use GMSK, but with different Gaussia...

Both GSM and DECT use GMSK, but with different Gaussian filters (BGT = 0.3 in GSM, BGT = 0.5 in DECT). What are the advantages of having a larger bandwidth time product? Why is the

Compute the area of each plate for parallel-plate capacitor, Q. For a paral...

Q. For a parallel-plate capacitor with plates of area A m 2 and separation d m in air, the capacitance in farads may be computed from the approximate relation Compute the

Electric discharge machining process, Describe the following in Electric di...

Describe the following in Electric discharge Machining Process(EDM). a) Dielectric fluids & their characteristic b) Electrodo feed Control c) Flushing System

Transfer characteristics , Transfer Characteristics The  transfer char...

Transfer Characteristics The  transfer characteristics of power MOSFET   transfer characteristic shown the variation of ID with V GS    denote the drain current  with shorted

Representation of negative number, Representation of Negative Number: ...

Representation of Negative Number: As  mentioned  in chapter 1 in 8085  negative  numbers are represented in 2 complement  form  and subtraction is  performed  using 2  comple

Explain the operation of oscillators, Q. Explain the operation of oscillato...

Q. Explain the operation of oscillators. Oscillator is a circuit that changes dc energy from the power supply into ac energy. An amplifier provided with a positive feedback bec

Clapp oscillator, derivation of frequency of oscillators clapp and derive C...

derivation of frequency of oscillators clapp and derive C effect?

Ac, power factor improvement

power factor improvement

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd