The Common Emitter Amplifier Circuit

The following is a simulation for a Common Emitter Amplifier Circuit.

Embed a running copy of this simulation

Embed a running copy link(show simulation in a popuped window)

Full screen applet or Problem viewing java?Add http://www.phy.ntnu.edu.tw/ to exception site list
Press the Alt key and the left mouse button to drag the applet off the browser and onto the desktop. This work is licensed under a Creative Commons Attribution 2.5 Taiwan License

Please feel free to post your ideas about how to use the simulation for better teaching and learning.
Post questions to be asked to help students to think, to explore.
Upload worksheets as attached files to share with more users.

Let's work together. We can help more users understand physics conceptually and enjoy the fun of learning physics!

The single stage common emitter amplifier circuit shown above uses what is commonly called "Voltage Divider Biasing". This type of biasing arrangement uses two resistors as a potential divider network and is commonly used in the design of bipolar transistor amplifier circuits. This method of biasing the transistor greatly Voltage Divider Network reduces the effects of varying Beta, ( β ) by holding the Base bias at a constant steady voltage level allowing for best stability. The quiescent Base voltage (Vb) is determined by the potential divider network formed by the two resistors, R1, R2 and the power supply voltage Vcc as shown with the current flowing through both resistors. Then the total resistance RT will be equal to R1 + R2 giving the current as i = Vcc/RT. The voltage level generated at the junction of resistors R1 and R2 holds the Base voltage (Vb) constant at a value below the supply voltage. Then the potential divider network used in the common emitter amplifier circuit divides the input signal in proportion to the resistance.
$V_B=\frac{R2}{R1+R2}Vcc$

Then $V_{RE}=V_B-V_{BE}$ (assume $V_{BE}=0.7V$ )
$I_E=\frac{V_{BE}}{R_E}$
and
$I_E=I_C+I_B=(1+\beta) I_B$
So $I_C=\beta I_B=\frac{\beta}{1+\beta}I_E$
Finally, $V_{CE}=V_{cc}-V_{RL}-V_{RE}=$ $V_{cc}-I_C R_L-I_E R_E>V_{sat}$
( $V_{sat}=0.2V$ )

You are welcomed to check out similar applet at Common Emitter Transistor Amplifier

Related Topics
	Subject	Started by	Replies	Views	Last post
	RLC circuit (AC) Electromagnetics	Fu-Kwun Hwang	18	199218	October 03, 2012, 08:51:39 pm by Fu-Kwun Hwang
	Common Emitter Transistor Amplifier Electronic	Fu-Kwun Hwang	4	35127	October 24, 2015, 04:38:08 pm by FamelJone
	Common Emitter Transistor Amplifier electromagnetism	ahmedelshfie	0	6946	May 16, 2010, 04:16:06 am by ahmedelshfie
	operational amplifier simulation Request for physics Simulations	alfalion	6	19487	October 26, 2015, 05:00:24 pm by chamDz
	Differential Amplifier Electronic	Fu-Kwun Hwang	0	6974	February 25, 2011, 10:53:27 pm by Fu-Kwun Hwang

	Author	Topic: The Common Emitter Amplifier Circuit (Read 81081 times)
0 Members and 1 Guest are viewing this topic. Click to toggle author information(expand message area).