00 op amp applications
TRANSCRIPT
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Case Study : How to do integration and differentiation beforedigital electronic computers Choice #1: analytically
BUT: for calculation of e.g. the times of high tide and low tides this was notfeasible
Solution: mechanical Integrators and Differentiators large machines
High cost, not always too accurate (http://www.usscod.org/tdc-restore.html)
From the 1950s 1960s: analogue electronic integrators with the help of OPAMPs
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Op Amp as an integrator: Why does it integrate the input voltage?
W. Bergholz GEE2 Spring 2012
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Op Amp as an integrator:
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Op Amp as an integrator:
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Improvement of plot?
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Improvement of plot?
Log log plot
straight line slope -1
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Op Amp as differentiator:
2 O d ff d h l
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Op Amp as differentiator:
21 O A i t t diff d th li ti
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Op Amp as integrator / differentiator:
Up to now, we have done our calculations in the timedomain
The magnitude and the phase shift of the output signal
can
of course - also be worked out using the frequency representation, i.e. the complex reactance of the
capacitor
including the negative sign of the gain
Xc = -j/CGain = - Xc/RI for the integrator (i.e. Inverting amp
and an additional phase shift of -90 degrees)
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Op amp as a square wave oscillator:
2 feedback
paths
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Op amp as a square wave oscillator:- How does this work out in detail?
- NI = non inverting input, II= inverting input
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Op amp as a square wave oscillator:- How does this work out in detail?
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Op amp as a square wave oscillator:- Result
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