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

Slack running fit, Illustrate the conventional representations of the follo...

Illustrate the conventional representations of the following guide to the selection of Fits: (i) Slack Running Fit (ii) Loose Running Fit (iii) Easy Running Fit (iv) No

The filter capacitor , It is needed to use a half-wave rectifier for a dc p...

It is needed to use a half-wave rectifier for a dc power supply that gives an average dc output voltage of 15 V and a maximum ±1V ripple is permitted. The rectifier feeds a load of

How single stepping can be done in 8086, How single stepping can be done in...

How single stepping can be done in 8086? By setting the Trace Flag (TF) the 8086 goes to single-step mode. In this mode, after the implementation of every instruction s 8086 ge

Hall effect - semiconductor, Explain hall affect and derive the mathematic...

Explain hall affect and derive the mathematical expression for hall coefficient, also describe its applications. Sol. Hall effect If a metal or semiconductor material carr

Discuss macro assembler directive, Discuss MACRO assembler directive wi...

Discuss MACRO assembler directive with example. MACRO: A sequence of instructions to that has a name is assigned is termed as macro. Macros and subroutines are the

Critical rate of rise of current - thyristor , Critical Rate of  Rise of ...

Critical Rate of  Rise of Current The maximum  rate of  increase of current  during  on state  which  the SCR  can tolerate is called  the critical rate of rise  of current  f

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

derivation of frequency of oscillators clapp and derive C effect?

Power in balanced three-phase circuits, Power in Balanced Three-Phase Circu...

Power in Balanced Three-Phase Circuits The total power delivered by a three-phase source, or consumed by a three-phase load, is found simply by adding the power in each of the

Show equivalent circuit of a synchronous machine, Equivalent Circuit of a S...

Equivalent Circuit of a Synchronous Machine A review of the material about elementary synchronous machines is very helpful at this stage to recall the principles of operation f

Name some application of serial communication, Name some application where ...

Name some application where you see use of serial communication. Within the world of serial communications, there are two different equipments are: DTE stand for Data Termin

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