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

Analysis in equilibrium, Analysis in equilibrium : Solution of Poisson'...

Analysis in equilibrium : Solution of Poisson's Equation with suitable boundary conditions - Non-equilibrium analysis: The electron and hole densities are no longe

Determine the transformer winding currents, Q. Three single-phase 100-kVA, ...

Q. Three single-phase 100-kVA, 2400:240-V, 60-Hz transformers (each ofwhich has an equivalent series impedance of 0.045+j0.16 referred to its low-voltage side) are connected to fo

How address and data lines are demultiplexed in 8085, How address and data ...

How address and data lines are demultiplexed in 8085? AD0-AD7 lines are multiplexed and the lower half of address A0-A7 is available only during T1  of the machine cycle. This

Arduino Microcontroller, Hi. Do you do projects with Arduino microcontrolle...

Hi. Do you do projects with Arduino microcontroller? How much does it cost?

Determine the transfer function in notch network, Q. The twin-tee or notch ...

Q. The twin-tee or notch network shown in Figure is often used to obtain band-reject characteristics. (a) Determine the transfer function V 2 /I 1 . (b) Find the angular freq

System diagram of complex programmable logic device, The system diagram for...

The system diagram for the proposed unit is shown below. The system operates on the principle of Time to Rate Conversion. Signals from the heart beat sensor are amplified

Calculating the damping ratio of the system, Consider the following mechani...

Consider the following mechanical system: a) Write a differential equation that describes the motion for this system. b) Take the Laplace transform of this equation and

.harmonics, describe the practical application of series resonance in ac ci...

describe the practical application of series resonance in ac circuits

Design a circuit for indicate the connection of a battery, You are asked to...

You are asked to design a circuit that indicates if a 12 V battery has been connected the correct way around to two terminals, A and B. To do this, you have chosen to use a special

Zero flag - sub subtract instruction , Zero Flag Since results  is n...

Zero Flag Since results  is non  zero in this  example zero  flag is reset.

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