Merits and demerits of fixed bias, Electrical Engineering

Assignment Help:

Merits:

1.      It is very simple to shift the operating point anywhere in the active region by just changing the base resistor (RB).

2.      A very small number of components are needed.

Demerits:

  • The collector current does not stay constant with difference in temperature or power supply voltage. Hence the operating point is unstable.
  • Variations in Vbewill change IBand so cause REto change. In turn this will alter the gain of the stage.
  • When the transistor is changed with other one, considerable change in the value of β can be supposed. Because of this change the operating point will shift.
  • For small-signal transistors (for example not power transistors) with comparatively high values of β (that is, between 100 and 200), this configuration will be prone to thermal runaway. Particularly, the stability factor which is a measure of the change in collector current with changes in reverse saturation current is almost β+1. To make sure absolute stability of the amplifier, a stability factor of less than 25 is chosen and so small-signal transistors comprises large stability factors.

 


Related Discussions:- Merits and demerits of fixed bias

Express the storedmagnetic energy, A relay is essentially an electromechani...

A relay is essentially an electromechanical switch that opens and closes electrical contacts. A simplified relay is represented in Figure. It is required to keep the fenomagnetic p

Feedback amplifier, explain working pricipal of nagative resistance oscilla...

explain working pricipal of nagative resistance oscillator

Describe watch dog timer and reaction timer, a. Given a timer with a termin...

a. Given a timer with a terminal count and a clock frequency of 10 MHz measure the following: (i) Range & Resolution (ii) Terminal count values needed to measure 3ms interval

FET, WHAT IS FET

WHAT IS FET

Compute efficiency of 4 hours full load at 0.8 power factor, Q. A 10-kVA tr...

Q. A 10-kVA transformer is known to have an iron loss of 150 W and a full-load copper loss of 250 W. If the transformer has the following load cycle, compute its all-day efficiency

Why the gain of the amplifier decreases if the ce is avoided, Q. Why the ga...

Q. Why the gain of the amplifier decreases if the CE is avoided? When the ce is connected in the circuit, ac signals get bypassed through it to the ground. In the absence of Ce

Negative voltage regulator series, Negative Voltage Regulator series with N...

Negative Voltage Regulator series with Nine voltage options - IC 7900 Series The IC 7900 series of fixed output negative voltage regulators are complements to the 7800 seri

What do you mean by continuous signals, Q. What do you mean by Continuous s...

Q. What do you mean by Continuous signals? Continuous signals are described by time functionswhich are defined for all values of t (a continuous variable). Commercial broadcast

Jfet, JFET The JFET (junction gate field-effect transistor) is a ...

JFET The JFET (junction gate field-effect transistor) is a long channel of semiconductor material, doped to consist of abundance of positive charge carriers (p-type), or

Calculate the fraction of particles - top plate, Consider a colloidal suspe...

Consider a colloidal suspension of latex particles confined between two plates. The plates are charged, so there is an electric potential difference V between them (as shown). The

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