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I'm trying to choose the right parameters in the simulation in order for the output to show a square wave of gain C1/C2 = 2V

Anyone know what I'm doing wrong? Thanks.

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The inverting input is not referenced to any DC voltage therefore it floats. It needs to have negative feedback via a resistor to keep it centred between the power rails. My recommendation is to use a feedback resistor (maybe 10 kohm) and also add a 10 kohm in series with C1. Make C1 a lot higher in value too.

The circuit I propose would have a gain of 1 and will remove the DC offset from the input signal. That is what I believe you are looking for. An op-amp's gain cannot be adequately defined purely by the ratio of capacitors.

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  • \$\begingroup\$ Are time, period and those parameters correct too? Becuase that's also giving me problems \$\endgroup\$ – tadm123 Jun 12 '18 at 8:48
  • \$\begingroup\$ @tadm123 you have inadequately defined requirements and an op-amp circuit that cannot work as shown. I'm trying to help you find a solution. The circuit I proposed has a ggain of 1 and removes the DC offset (as would your circuit due to C1). Apart from that I have no idea what your aims are. If you can elaborate please do so. An op-amp with a bandwidth of 100 MHz will not be useful for the signal frequency you are proposing BTW. \$\endgroup\$ – Andy aka Jun 12 '18 at 8:53
  • \$\begingroup\$ Well I'm trying to plug in any parameters to simply make the amplifier work but I need to design it in this manner (two capacitors). It's not really a very sophisticated design or very complete, just a simple example of an amplifier with two capacitors. Any values whatsoever will do really as long as it works.. \$\endgroup\$ – tadm123 Jun 12 '18 at 9:25
  • \$\begingroup\$ For example I tried doing the simulation with a Sinusoid signal and it works. But I just simply need to do the same but with a pulse (or square) signal, but I ran into problems. postimg.cc/image/8oy75gr4b postimg.cc/image/uo4lso08r \$\endgroup\$ – tadm123 Jun 12 '18 at 9:36
  • \$\begingroup\$ I'm completely sure the problem is with putting wrong values on the transient and square signal settings. \$\endgroup\$ – tadm123 Jun 12 '18 at 9:43

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