Explain working of common drain amplifie, Electrical Engineering

Assignment Help:

Q. Explain working of Common drain amplifie?

When an ac signal drives the gate of JFET, it produces an ac drain current. It flows through Rs and produces an ac output voltage that is approximately equal to the input voltage and is in phase with it.

1895_COMMON DRAIN AMPLIFIER.png

fig.(a)  COMMON DRAIN AMPLIFIER

In the figure, R3 = Rs.

From the figure:

Vin = Vgs+gmVgsRs

Vin = (1+gmRs) Vgs

Vout = gmVgsRs

Vout/Vin = gmVgsRs/ (1+gmRs) Vgs = Rs/(1/gm)+Rs

Rs> = 1/g

Vout = Vin Rs/(Rs+(1/gm))

Zin depends on the type of biasing circuit used. In case of voltage divider biasing circuit, Zin = R1 and R2 in parallel.

The common drain amplifier with high input impedance and near-unity voltage gain is used as a buffer amplifier. The common drain amplifier is also known as "SOURCE FOLLOWER".


Related Discussions:- Explain working of common drain amplifie

Calculate the power dissipated in the amplifier, For the amplifier circuit ...

For the amplifier circuit shown in Figure with R i ≅ ∞,R o ≅ 0,A = 10,R L = 100 , and v in = 1 V, calculate the power dissipated in the amplifier if the voltage at the power-s

Determine the antennas power gain and beamwidth, Q. A paraboloidal antenna ...

Q. A paraboloidal antenna has an aperture ef?ciency of 0.6 and a diameter D = 100λ at 6 GHz. Illumination by the feed is such that the beamwidths of the principal-plane secondary p

Explain the purpose of the global descriptor table register, Explain the pu...

Explain the purpose of the global descriptor table register. The GDTR stand for global descriptor table register and IDTR stand for interrupt descriptor table register conta

What is ringer circuit in telephone hand set, Q. What is Ringer Circuit in ...

Q. What is Ringer Circuit in telephone hand set? Purpose of the ringer is to alert destination party of incoming calls. Audible tone from the ringer should be load enough to be

Discuss electrical properties of insulating materials, Discuss electrical p...

Discuss electrical properties of insulating materials. Electrical properties of an insulating material are As Follows: Insulation resistance - It is the property, through

Waveguides, Why are waveguides not used at low frequencies?

Why are waveguides not used at low frequencies?

Determine whether the systemnoise, The expression given in Problem for (S 0...

The expression given in Problem for (S 0 /N 0 )PCM is plotted for a sinusoidal message in Figure to show the performance curves for a PCM system using a polar waveform. (a) Comm

Determine the output voltage, Q. An inverting amplifier is designed with th...

Q. An inverting amplifier is designed with three inputs, v 1 , v 2 , and v 3 , as shown in Figure. Determine the output voltage. Then indicate how the circuit may be modified to pe

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