Schematic symbols, Electrical Engineering

Assignment Help:

Schematic Symbols

The junction gate field-effect transistor or JFET gate is sometimes drawn in the middle of the channel (in place of at the drain or source electrode as in these illustrations). This symmetry suggests that "drain" and "source" are interchangeable, thus the symbol should be used just only for those JFETs where they are indeed interchangeable (that is not true of all JFETs).

Formally, the style of the symbol should depict the component inside a circle (presenting the envelope of a discrete device). This is right in both the US and Europe. The symbol is generally drawn without the circle while drawing schematics of integrated circuits. More recently, the symbol is frequently drawn without its circle even for discrete devices.

In each case the arrow head depicts the polarity of the P-N junction formed in between the channel and gate. The arrow points from P to N, the direction of conventional current while forward-biased as with an ordinary diode. An English mnemonic is that the arrow of an N-channel device "points in".

To pinch off the channel, it requires a certain reverse bias (VGS) of the junction. This "pinch-off voltage" changes considerably, even among devices of similar type. For instance, VGS (off) for the Temic J201 device varies from -0.8V to -4V. Typical values change from -0.3V to -10V. To switch off an n-channel device needs a negative gate-source voltage (VGS). On the other hand, to switch off a p-channel device needs VGS positive. In usual operation, the electric field developed through the gate must block conduction in between the source and the drain.


Related Discussions:- Schematic symbols

Functions of the physical layer in the internet model, (a) Describe the f...

(a) Describe the four functions of the physical layer in the Internet Model. (b) (i) With the help of a diagram describe the main stages involved in the digitization of a

Compute the load power factor, Considering Figure, let balanced positive-se...

Considering Figure, let balanced positive-sequence, three-phase voltages with ¯V AB = 100√3 0° V (rms) be applied to terminals A, B, and C. The three-phase wye-connected balanced

Explain resistivity, Explain Resistivity. Resistivity : Resistance R o...

Explain Resistivity. Resistivity : Resistance R of a wire containing cross-sectional area A and length L maintain the relationship, - R α L and R α 1/A; that is resulting R α

Threshold switching voltage, Analogue Threshold switching a) Include a...

Analogue Threshold switching a) Include a variable potential divider to the schematic diagram to control the transistor base voltage b) Include the potential divider compon

Software, Write a computer program to implement the finite difference metho...

Write a computer program to implement the finite difference method. The program can be in any computer language that is available within the school. Set up the code to find the pot

Role of erc - salient features of nep, Role of ERCs: A National Elect...

Role of ERCs: A National Electricity Policy is one of the key instruments for providing policy guidance to the Electricity Regulatory Commissions in discharge of their functio

Differential amplifier to eliminate the common-mode voltage, Q. Differentia...

Q. Differential amplifier to eliminate the common-mode voltage? The transducer in some cases may have a local ground that cannot be disconnected. In such a case, a separate gro

Find appropriate values of sampling rate - nyquist rate , 1. Find the Nyqu...

1. Find the Nyquist rate for the following signals: (a) x(t) = 5 sin 3000Πt cos 4000Πt (b) A binary channel with bit rate 36000 bps is available for PCM voice transmission.

Dc machines, how unbalanced effect in wave winding is considered to be bala...

how unbalanced effect in wave winding is considered to be balanced?

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