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

Explain the significance of the coupling capacitor, Q. Explain the signific...

Q. Explain the significance of the Coupling capacitor and the RE - CE circuit. The function of the coupling capacitor is to isolate the amplifier input circuit from the source.

Direct addressing , Direct Addressing In this  addressing  mode one  o...

Direct Addressing In this  addressing  mode one  of the  operands is the  data stored  in the memory. The memory  address of the  operand is directly  given in the instruction

#electrical wiring, how to draw electric circuit for staircase wiring using...

how to draw electric circuit for staircase wiring using 3 two way switches?

Basic structure of an scr and the common circuit symbol, Q. Draw the basic ...

Q. Draw the basic structure of an SCR and the common circuit symbol ? The SILICON CONTROLLED RECTIFIER, usually referred to as an SCR, is one of the families of semiconductors

Power and power distribution, design a single phase circuit from a supply p...

design a single phase circuit from a supply point to a load

How to reduce cost in embedded systems, Question: a) Give three ways h...

Question: a) Give three ways how to reduce cost in embedded systems. b) What is a microcontroller? How is it different to a microprocessor? c) Briefly comment on the "A

Zener breakdown voltage, (a) For the Zener diode series voltage regulator s...

(a) For the Zener diode series voltage regulator shown in the Figure. calculate V L , I Z , V R and P Z for R L = 1.2 KΩ and repeat it for R L = 3 KΩ ? Consider Zener breakdow

What is the procedure of binary division, Q. What is the procedure of Binar...

Q. What is the procedure of Binary Division? The Binary division is the repeated process of subtraction, just as in decimal division. Signed Numbers Representation If w

Illustrate working of differential amplifier, Q. Illustrate working of Diff...

Q. Illustrate working of Differential Amplifier? Figure shows a weighted differencing amplifier, where "weighted" refers to the fact that the output voltage has the form v o =

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