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 suitability of copper, Explain  the  suitability  of  coppe...

Explain  the  suitability  of  copper that  is  used  as  electrical  conducting materials. Copper : Pure annealed is utilized for the winding of electrical machines. High pur

Daa decimal adjust accumulator instruction , DAA Decimal Adjust Accumulator...

DAA Decimal Adjust Accumulator Instruction This  instruction adjusts the contents  of the accumulator  into BDC (Binary Coded Decimal )  form  after a BCD  addition. It should

Aims of the tariff policy - electricity policies, Aims of the Tariff Policy...

Aims of the Tariff Policy - electricity policies: The aims of the National Tariff Policy are to: 1. Ensure availability of electricity to consumers at reasonable and compet

Physical operation of the junction of diode, Q. Physical operation of the j...

Q. Physical operation of the junction of diode? The physical operation of the junction can be described in terms of the charge-flow processes. Usually there is a greater concen

Develop and execute a pspice program, Develop and execute a PSpice program ...

Develop and execute a PSpice program to solve for the current I 2 in Figure.

Gate source cut off voltage, Q. Gate source cut off voltage? It is the ...

Q. Gate source cut off voltage? It is the gate source voltage where the channel is completely cut off and the drain current becomes zero.It is interesting to note that the valu

Determine the analog output voltage, Q. Analyze the 2-bit R-2R ladder-netwo...

Q. Analyze the 2-bit R-2R ladder-network D/A converter, and corresponding to binary 01, 10, and 11, obtain the equivalent circuits and determine the analog output voltage as a frac

Binary codes, what are the types of binary codes

what are the types of binary codes

Define resistance strain gauge, Q. Define Resistance Strain Gauge? Mech...

Q. Define Resistance Strain Gauge? Mechanical and civil engineers routinely employ the dependence of resistance on the physical dimensions of a conductor to measure strain. A s

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