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

Interpreter- high level language, Interpreter- High level language T...

Interpreter- High level language The interpreter is a program  which  translates the high  level  program  into  objects  program  statement wise . it reads one statement of

Port address - address bus , Port Address The port  address  is of 8 bi...

Port Address The port  address  is of 8 bit  it is range from 00H  to FFH. It means  there may be total  i 256 input  ports and 256  output  port which can be accessed by 8085

Intrinsic semiconductor, Draw a graph illustrating how resistivity varies w...

Draw a graph illustrating how resistivity varies with temperature for an intrinsic semiconductor. b) Gallium nitride, GaN, has an energy gap of 3.36 eV at 300 K. Calculate the w

Find the maximum radiation intensity, Q. An antenna has beam widths of 3° a...

Q. An antenna has beam widths of 3° and 10° in orthogonal planes and has a radiation ef?ciency factor of 0.6. Find the maximum radiation inten- sity if 1 kW is applied to the anten

Differential amplifier, Ask question #Minimum 100 words What is neeed of d...

Ask question #Minimum 100 words What is neeed of differential amplifier

Explain factors affecting permeability and hysterisis loss, Explain the fac...

Explain the factors affecting permeability and hysterisis loss. Factors affecting permeability and hysterisis loss: When the initial permeability is high, the hysterisis los

Differentiate between dual beam and dual trace oscilloscope, Q. How do you ...

Q. How do you differentiate between dual beam and dual trace oscilloscope? Sol. There are two separate vertical input channels A, B and these use separate attenuator and prea

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