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

Tardy billing and poor revenue collection, Tardy Billing and Poor Revenue C...

Tardy Billing and Poor Revenue Collection Prolonged disputes, connivance, lack of consumer friendly policies, incorrect identification of category, fictitious billing (of non-

Demand meters, Demand Meters Demand meters measure volt-amperes (in kV...

Demand Meters Demand meters measure volt-amperes (in kVA), that merge both reactive (reflected) and actual (consumed) power. In its easiest form, a demand meter has a gauge wh

Write shorte note on carbon, Write shorte note on Carbon. Carbon: The...

Write shorte note on Carbon. Carbon: The rate of commutator wear in electrical machines is greatly decreased by using brushes made of carbon. Carbon (C) is also used in autom

Spectral analysis and signal bandwidth, Q. Show Spectral Analysis and Signa...

Q. Show Spectral Analysis and Signal Bandwidth? Spectral analysis is based on the fact that a sinusoidal waveform is completely characterized by three quantities: amplitude, ph

Static characteristics of the npn silicon bjt, Consider the common-emitter ...

Consider the common-emitter BJT circuit shown in Figure (a). The static characteristics of the npn silicon BJT are given in Figure (b) along with the load line. Calculate iB for v

Holding current - thyristor , Holding current The holding  current i...

Holding current The holding  current is  the value  of on state  current  required  to maintain  conduction once the  device  the device has  fully timed  on and  the  gate

Conductors for lines, Conductors for Lines The sizing of conductor mus...

Conductors for Lines The sizing of conductor must depend upon the load it is expected to serve and other factors, such as capacity required in future. Or else conductors/cable

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