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OP-AMP Problem - help with schematics

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Junior Member level 3
Apr 28, 2009
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op amps problems

Hello All,

Anyone who could explain to me the function of the circuit in the attached file?

Thank you,


op amp problems

the answers to your questions there are:

1) none.
2) none.

it is a circuit designed by drunks and for drunks.

op-amp circuit problem

If you correct the drawing error in inverter circuit and let the input voltage toggle between GND and 5V, it's an operational negative voltage supply. The switch has to be toggled continuously rather than "turned on" once.

Re: OP-AMP Problem

I am not sure about the circuit.But you can get think of that.

The circuit looks like a modulator.Like CW modulator(carrier wave modulator used in morse code generator)
The switch acts as message input.The vin is a carrier frequency.
The opamp acts as a low pass filter.The opamp works for low band carrier and will not allow any high frequency noise.
The two FETs are acting as an invetor and its output is connected through a capacitor so after pressing the switch, a pulse voltage goes out and it is captured in a big capacitor (in negative supply pin of opamp).
Please understand that i think so the circuit is, i am not sure.

Re: OP-AMP Problem

1. But still it will amplify the Vin?
2. Is the circuit in the box cannot disable the op-amp? Does the op-amp still works when swutch is toggle?
3. Can you please sight some application of this circuit?

Thank you so much!

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