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Any fag wanna help with my lab problems?
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Thread replies: 17
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Alright guys, I need help with my lab report suggestions. The problem is that I made a linear Voltage controlled frequency generator and am getting a 'ramping' effect on my integrator circuit. Do you guys know how i can possibly solve this? The output i should be getting is perfect square and triangle waves. pic related.
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This is what the output wave should be...
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Did you try taking it apart and putting it back together?
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also, this is my circuit lay out
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>>901224
yes nigga, i did
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>>901224
at this point of time, im thinking the problem is with the op amp in the center that has the capacitor attached to it. because the entire circuit is dependent on this integrator. the most annoying thing is that this only happens when the input voltage is down at 0.1V.
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>>901222
well you have the circuit simulated
so you can probe various points starting from the left working your way to the right
in both the sim and the real version
and find out where the results diverge.
then you will see where the error is.
thats how fault finding works.
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>>901228
Thing is that the circuit achieves the requirements for when the input voltage is higher than 0.1V with really nice and crisp waveform, the only exception is when it is at 0.1V. So i was thinking it was a problem with the voltage satueration rate of the capacitor in the integrator. In specific, it charges really fast, then discharges over a longer period of time. The funny thing is that the frequency for the charge cycles are pretty much proportionate to the rest of the circuit.
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>>901222
Dead thread is gonna be a dead thread enjoy a gif
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>>901222
>when the input voltage is down at 0.1V

Excuse my ignorance, but what exactly is this "input voltage" you speak of?
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If the capacitor is electrolytic, try switching the position of the terminals.

I remember having a problem because of this
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>>903069
It was a ceramic :(
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>>901577
>>901225
It's on the far left of the circuit. It's labeled as 5V DC
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>>901222
Have you tried duct tape?
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>>903560
It's already held together, duct tape holds things together.
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>>901222
My gut reaction says that maybe you should try a different op I remember once getting a some 741 that were old and super noisy. However the datasheet says that the input offset should be accurate to 1mV.

741 also have a voltage offset that can be controlled through a pot, make sure you check the datasheet and set that up properly.

Also failing that you can always just write it into the report.
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>>904589
Fair enough. Have you tried a pry bar?
Thread replies: 17
Thread images: 4

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