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OpAmp beginner here. I'm trying to do the simple 1KHz, 1V p-p sine wave amplification circuit using TL071 or similar OpAmp.

Simulation currently in LTSpice.

I've biased the VCC to half to try to achieve a good voltage swing but I'm getting the waveform clipped, seems that the Opamp is amplifying my DC bias also?

I don't expect this Opamp to be rail-to-rail, of course.

First, here's the output waveforms: enter image description here

V(out) is the small output signal, red is AC sinewave, green is biased waveform, centered at VCC/2.

Here's my circuit:

enter image description here

Any help? I'm new to this world of opamps and struggling a bit, thank you!

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The 'ground' on R3 becomes the 'zero reference' for the amplification. This should be connected to Vcc/2. Otherwise you will get strange results (what you are seeing).

There is some good information here about how to generate a virtual ground for this type of single-supply circuit: http://tangentsoft.net/elec/vgrounds.html

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