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

Resultant force, State and prove parallelogram law of forces and explain i...

State and prove parallelogram law of forces and explain it''s applications

Why earthing is required for any electrical equipments, Why earthing is req...

Why earthing is required for any electrical equipments, domestic installation and service building etc? For TL coaches what is the minimum I.R. value needed for new wiring? An

Explain the construction of depletion mosfet, Q. Explain the construction o...

Q. Explain the construction of depletion MOSFET? A slab of p-type material is formed from a silicon base and it is referred to as the substrate. It is the foundation upon which

Illustrate the basic concept of machine cell design, a) Write short notes o...

a) Write short notes on part feeding devices and transfer mechanism. b) Explain with example automation for machining operation with relevant diagrams. c) discuss different p

Electrical circuits, equivalent circuit for transistor using h parameters

equivalent circuit for transistor using h parameters

Fourier Series, State by inspection (i.e. without performing any formal ana...

State by inspection (i.e. without performing any formal analysis) all you can about each of the periodic waveforms shown in FIGURE 1 in terms of their Fourier series when analysed

Calculate the total power supplied to the divider circuit, There is often a...

There is often a need to produce more than one voltage from a single supply using a voltage divider. For example, the memory components of many personal computers require voltages

Explain the asynchronous decade counter, Explain the Asynchronous Decade Co...

Explain the Asynchronous Decade Counter? The binary counters earlier introduced have two to the power n states. But the counters with states less than this number are as well

Standby mode, Standby mode:In this mode, one processor is active and other ...

Standby mode:In this mode, one processor is active and other is on standby, both software and hardware wise. Standby processor brought online when active processor fails. A vital r

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