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

Superposition, find current across r3 with two voltage as sources

find current across r3 with two voltage as sources

Show the amenability to computer processing, Q. Show the Amenability to com...

Q. Show the Amenability to computer processing? Due to the digital data collected and stored in the form of a matrix, the same becomes amenable to processing on computers. By f

Nor gate - introduction to microprocessors , NOR Gate NOR means NOT OR ...

NOR Gate NOR means NOT OR . it complements the  output  of an OR  gate.  The symbol  of Nor  gate in fig. (a) shows that a Nor  gate  comprises  of an OR  gate followed  by a N

Dee, how do we construct wind turbines. procedures methods

how do we construct wind turbines. procedures methods

Analysis of aspects of design for excellence, We commissioned a 'bad practi...

We commissioned a 'bad practice exemplar' by asking Plexus to modify a good design (provided by Valor) to demonstrate the most likely kinds of faults in each of the areas Design fo

Loops and subroutines, 1.....If viewing this through the Assignment tool, c...

1.....If viewing this through the Assignment tool, click the title above to go to the Submissions area. Introduction The purpose of this experiment is to examine the opera

Stc set carry instruction, STC Set Carry Instruction This instruction ...

STC Set Carry Instruction This instruction  sets   the carry  flag  to 1. The  instruction format is STC Flags except carry no other  flags are affected

Works, Microprocessor and its Applications

Microprocessor and its Applications

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