Difference between revisions of "TF EIM Chapt9"

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[[File:TF_EIM_GenOpAmp_EquivCirct.png]]
 
[[File:TF_EIM_GenOpAmp_EquivCirct.png]]
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Gain = <math>A_o \equiv \frac{V_{out}}{V_2-V_1}</math>
  
 
==Common Mode==
 
==Common Mode==
  
 
Common mode input is defined as the situation where the two inputs are equal (<math>V_1 = V_2)</math>.  In this case<math> V_1</math> is inverted and will cancel the input <math>V_2</math> so the output becomes Zero in the ideal Op Amp.
 
Common mode input is defined as the situation where the two inputs are equal (<math>V_1 = V_2)</math>.  In this case<math> V_1</math> is inverted and will cancel the input <math>V_2</math> so the output becomes Zero in the ideal Op Amp.

Revision as of 02:21, 12 April 2011

Operational Amplifiers (Op Amps)

The operational amplifier is monolithic (single chip) integrated circuit composed of transistors, resistors, diodes, and other components.

The small package produces a device with small capacitance and inductance which is superior to assembling the equivalent circuit with individual components.


Op-Amp

the "-" sign indicates the inverting input terminal and the "+" indicates the non-inverting input.

A positive going input voltage at the non-inverting ("+") input produces a positive going output.

A positive going input voltage at the inverting ("+") input produces a negative going output.

In other words the output is in phase when the input is non-inverting and 180 degrees out of phase when the input is inverting.

TF EIM GenOpAmp.png

Equivalent circuit

TF EIM GenOpAmp EquivCirct.png


Gain = [math]A_o \equiv \frac{V_{out}}{V_2-V_1}[/math]

Common Mode

Common mode input is defined as the situation where the two inputs are equal ([math]V_1 = V_2)[/math]. In this case[math] V_1[/math] is inverted and will cancel the input [math]V_2[/math] so the output becomes Zero in the ideal Op Amp.