i designed for twin-t for 50 Hz and BW=2

I have to use single supply opamp but i cant get it single supply opamp thing ...

Can anyone tell me which node i have to do ground , which node i have to do Vcc/2?

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i changed Vee to GND and GND to Vcc/2, this is the result maybe i miss understand something but like i said i really dont get single opamp design.

maybe it is not that clear but it's starts from -15dB.Why is it starts from 0db like previously. You can see circuit at up , my design is perfectly working. Like i said maybe i did something wrong at single supply design

Can someone tell me more spesific which part i have to edit for work perfectly before?

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i think -15 dB thing, because of cap. Resistor and Cap make filter and this affect all system. Finally, I deleted from there and i added Vcc/2 at input , it's work without problem. There is only offset problem. Output voltage has 2.5V dc offset. Maybe it's come from single opamp topology i dont know...

Anyway this is circuit

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Transient Analysis

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AC Analysis

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1 Answer 1


The ground in your existing circuit needs to become Vcc/2, and the node labeled Vee in the existing circuit needs to become the new ground.

Obviously, the input and output signals will now be referenced to Vcc/2 instead of ground. There are various ways of dealing with this, depending on what you're interfacing to.


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