Fixed bias with emitter resistor, Electrical Engineering

Assignment Help:

Fixed bias with emitter resistor:

711_Usage.png

Figure: Fixed bias with emitter resistor

The fixed bias circuit is changed through attaching an external resistor to the emitter. This resistor establishes negative feedback which stabilizes the Q-point. From the voltage law of Kirchhoff, the voltage across the base resistor is

VRb = VCC - IeRe - Vbe.

From the law of Ohm, the base current is

Ib = VRb / Rb.

The manner feedback controls the bias point is like this. If Vbe is stay constant and temperature get increases, emitter current also increases. Though, a larger Ie increases the emitter voltage Ve = IeRe, in turn which decreases the voltage VRb across the base resistor. A lower base-resistor voltage drop decreases the base current that results in less collector current since Ic = ß IB. Collector current and emitter current are related through the Ic = α Ie with α ≈ 1, thus an increase in emitter current with temperature is opposed, and operating point is kept stable.


Related Discussions:- Fixed bias with emitter resistor

Show a schematic diagram of the seven- segment decoder, Q. Digital watches ...

Q. Digital watches display time by turning on a certain combination of the seven-segment display device. (a) Show a typical seven-segment display. (b) Develop a truth table f

Incorrect Solution, Hi there i just asked for question and answer for 5 cha...

Hi there i just asked for question and answer for 5 chapter and i just receive some of them in word the rest are in apiece of paper which is unprofessional could you please have l

What are the uses of mosfet, Q. What are the uses of MOSFET? The most c...

Q. What are the uses of MOSFET? The most common use of MOSFET transistors today is the CMOS (complementary metallic oxide semiconductor) integrated circuit which is the basis f

Net force on the wire due to the interaction of the b-field, Q. (a) Show by...

Q. (a) Show by applying Ampere's circuital law that themagnetic field associated with a long straight, current-carrying wire is given by B φ = µ 0 I/(2πr), where the subscript φ d

Fourier transform - filtering, Fourier transform  (filtering) (i) Perf...

Fourier transform  (filtering) (i) Perform low pass filtering in the frequency domain. Write and m-file lowfft.m which does this operation. lowfft.m function lowfft im

Determine the peak fundamental component of the mmf, Q. A two-pole, three-p...

Q. A two-pole, three-phase synchronous generator has a balanced three-phase winding with 15 turns per phase. If the three-phase currents are given by i a = 100 cos 377t, i b =

Explain the discrete time systems, Explain the Discrete Time Systems? A...

Explain the Discrete Time Systems? A system operates on an input signal, x[n] and output the results, y[n]. For example, a digital filter (a system) can be represented by the f

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

What do you mean by transconductance, Q. What do you mean by Transconductan...

Q. What do you mean by Transconductance? The  control that the gate voltage has over the drain current is measured by transconductance and is similar to the transconductance of

Line Protection., The Lennox to Bowmanville 500 kV circuit, spanning a dist...

The Lennox to Bowmanville 500 kV circuit, spanning a distance of about 180 km, has series (inductive) impedance j 0.0224 pu and shunt (capacitive) admittance j 2.34 pu, quoted on b

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