Difference between revisions of "TF EIM Chapt9"
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[[File:TF_EIM_GenOpAmp.png]] | [[File:TF_EIM_GenOpAmp.png]] | ||
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Op Amps usually has two bias supplies in order to produce a high gain as determined by the difference in the input voltages. The output can't be larger than the supply bias. | Op Amps usually has two bias supplies in order to produce a high gain as determined by the difference in the input voltages. The output can't be larger than the supply bias. | ||
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| + | ==Op Amp Basics== | ||
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| + | [[File:TF_EIM_BiPolarOpAmp.png]] | ||
Revision as of 03:56, 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.
Equivalent circuit
Gain = Open loop gain = gain when there isn't anything hooked up to the op amp to draw current from it.
Common Mode
Common mode input is defined as the situation where the two inputs are equal (. In this case is inverted and will cancel the input so the output becomes Zero in the ideal Op Amp.
Op Amps usually has two bias supplies in order to produce a high gain as determined by the difference in the input voltages. The output can't be larger than the supply bias.
Op Amp Basics
