What is transconductance, Electrical Engineering

Assignment Help:

Q. What is transconductance? Explain its significance from the transfer characteristics.

Transconductance is the transistor gain of the JFET; it indicates the amount of control the gate voltage has on the drain current. The transconductance is defined as

    gm = d(ID)/d(VGS)

Using the expression for the ideal drain currents derived, we can write the expressions for the transconductance.

The drain current for n-channel depletion mode device in the non-saturation region region was given by equation for the pinch off current.

The derivation of the equation for the transconductance leads to the relation shown below

    gms = (-2IDSS)(1-VGS/VP)/VP

The transconductance shows the significance of the transfer characteristics of a JFET.

1987_What is transconductance.png

The transfer characteristic of an FET relate the transfer of the input directly with the output. That is the drain current is directly plotted with the gate source voltage. The graph on the left slowly diminishes in its amplitude as it approaches the x axis. In theory the graph touches the x axis and channel pinches off. But in practical sense the graph does not tough the x axis but goes parallel to it with out touching it. For this reason the gm of the JFET is always a constant value. The transconductance of the JFET relates the ease with which the drain current flows at a particular value of the gate source voltage. The measure of transconductance is done in siemens.


Related Discussions:- What is transconductance

Charging of the capacitor, Charging of the capacitor: Considering the ...

Charging of the capacitor: Considering the below diagram, with slight approximation the ripple voltage can be supposed as triangular. To the cut-out point from the cut-in poin

Electrical machine, Design a suitable double –layer lap winding for a 6-pol...

Design a suitable double –layer lap winding for a 6-pole dc armature with 18 slots and two coil sides per slot. Give values of front-pitch, brack–pitch and commutator pitch. Draw t

Explain the properties of low resistivity materials, Explain the properties...

Explain the properties of low resistivity materials. Low resistivity materials: The conducting materials containing resistivity from 10 -8 to 10 -6 ohm-m come under this cl

Magnetic ckt''s, what is the difference between statically and dynamically ...

what is the difference between statically and dynamically induced emf''s

Voltmeter transistor, explain basic working of voltmeter transistor

explain basic working of voltmeter transistor

Explain biased and double clipper circuits, Q. Explain biased and double c...

Q. Explain biased and double clipper circuits.   Clipper can be either forward biased or reverse biased. If a battery is connected in series with the diode in a positi

Essay, Transmission parameters are more effective than the hybrid parameter...

Transmission parameters are more effective than the hybrid parameters for simulation of the transmission line

Demodulators for FM, Demodulators for FM Figure  shows a block diagram ...

Demodulators for FM Figure  shows a block diagram of a general FM demodulator, which is implemented by generating an AM signal whose amplitude is proportional to the instantane

What is the function of ct and p.t, Q. What is the function of CT and P.T a...

Q. What is the function of CT and P.T and where they are used? Ans: The full form of CT is Current transformer and is used for calculating of current. The full form of PT is

Why do we cascade amplifiers, Q. Why do we cascade amplifiers? Why is RC co...

Q. Why do we cascade amplifiers? Why is RC coupling the most widely used coupling between 2 stages of a cascading amplifier? The voltage or power gain or frequency response obt

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