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 term telecommunication, Question 1 Explain the term telecommun...

Question 1 Explain the term telecommunication and how its implied meaning has changed over time and outline major developments in telecommunication technologies Question 2

Static scherbius drive - motor control , Static  scherbius  Drive B...

Static  scherbius  Drive By using  this scheme, below and above  synchronous speed can be obtained for an induction motor. There are  two possible  configurations to obtain  s

Digital Signal Processing, What is the difference between the unit step fun...

What is the difference between the unit step function u(n+4) and the time-scaled function u(2n+8)

Determine the fault current and the bus voltages, The one line diagram of a...

The one line diagram of a simple three-bus power system is shown in the figure below.  Each generator is represented by an emf behind the transient reactance.  All impedances are e

Define electrical energy, Electrical energy If the power is measured in...

Electrical energy If the power is measured in watts and the time in seconds then the unit of energy is watt- seconds or Joules.

Explain the importance of distributing frames, Q. Explain the Importance of...

Q. Explain the Importance of distributing frames? Basically four levels of cabling are used as displayed in Figure. At the subscriber end, drop wires are taken to a distributio

Superposition theorem, what is the disadvantages of superposition theorem?

what is the disadvantages of superposition theorem?

Prepare the equation for drift velocity and mobility, Question 1: (a) O...

Question 1: (a) Outline the architecture of MIT's iLabs. Design a diagram supporting your explanation. (b) Give advantages/disadvantages of the MIT Microelectronics iLabs wi

Compute the efficiency of the motor, Q. A 10-hp, 230-V dc shunt motor takes...

Q. A 10-hp, 230-V dc shunt motor takes a full- load line current of 40 A. The armature and field resistances are 0.25 and 230 , respectively. The total brush-contact drop is 2 V,

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