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

Explain noise, Explain Noise Noise is unwanted signals which degrade t...

Explain Noise Noise is unwanted signals which degrade the desired signal content and therefore the performance of the system. Noise might be produced either externally or inte

Explain the term superscalar architecture, Question 1: a) Describe how...

Question 1: a) Describe how pipelining can improves the efficiency of the fetch-execute cycle. b) Explain the term superscalar architecture. c) Explain the term prin

Finite state machine, the tutorial assignment is part of my thesis work and...

the tutorial assignment is part of my thesis work and i need help in it please

Neutral line in transformer, thus secondary winding of transformer consists...

thus secondary winding of transformer consists of neutral line or not?

Magnetic circuits, Magnetic circuits To  see  how  this   is  used   i...

Magnetic circuits To  see  how  this   is  used   in  practice, consider a coil of N turns wound onto a closed ring shaped former with a very high (note:    r (steel) = 200

Define hrq, Define HRQ? The hold demand output requests the access of t...

Define HRQ? The hold demand output requests the access of the system bus. In non- cascaded 8257 systems, this is linked with HOLD pin of CPU. In cascade mode, this pin of a sla

First quadrant or class a chopper, First Quadrant or Class A chopper A ...

First Quadrant or Class A chopper A chopper  two mode operation of class  A chopper  can be explained as follow.

Explain about automatic stabilizers, Q. Explain about Automatic Stabilizers...

Q. Explain about Automatic Stabilizers? Automatic Stabilizers: Government fiscal policies which have effect of automatically moderating cyclical ups and downs of capitalism.

DECISIEN FEEDBACK, Do you provide me matlab code for comparison the perfor...

Do you provide me matlab code for comparison the performance of decision feedback equalizer over MLSE

Example register to memory , Example  Register  to Memory Example ...

Example  Register  to Memory Example : Write assembly language  statement  to copy 25H  stored  in register D to memory location 3052H. Solution :   Assuming  3050H is 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