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

Unit to measure the electric charge q, Unit to measure the electric charge ...

Unit to measure the electric charge Q?? The unit used to measure the quantity of electrical charge Q is called the coulomb C

Find voltage in circuit using the ideal op-amp technique, Q. Find v o in t...

Q. Find v o in the circuit shown in Figure by using the ideal op-amp technique.

Solid-state control of synchronous motors, Solid-State Control of Synchrono...

Solid-State Control of Synchronous Motors  The speed of a synchronous motor can be controlled by changing its supply frequency. With variable-frequency control, two modes of op

Diode, using a sketch explain the frequency response of rc coupled transist...

using a sketch explain the frequency response of rc coupled transistor amplifier

Erc and kpi, ERC and KPI The company requires understanding the strate...

ERC and KPI The company requires understanding the strategic and nearing term impact of the Regulator's orders / tariff approval process. Once these dimensions are understood,

Explain about delay system, Q. Explain about Delay System? Delay Syste...

Q. Explain about Delay System? Delay System: A class of telecommunication networks, like data networks, places the message or call arrivals in a queue in the

Consequent effects on the real and reactive power losses, Q. Consider an up...

Q. Consider an upgrade of a three-phase transmission system in which the operating line-to-line voltage is doubled, and the phase or line currents are reduced to one-half the previ

Compute the pull on the plunger, Q. A sectional view of a cylindrical iron-...

Q. A sectional view of a cylindrical iron-clad plunger magnet is shown in figure. The small air gap between the sides of the plunger and the iron shell is uniform and 0.25 mm long.

Low investments in transmission and distribution system, Low Investments in...

Low Investments in Transmission and Distribution System The investment on T&D system in our country has commonly been lower than that on generation. It is hugely believed in

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