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I am trying to simulate the follwoing circuit in LTSpice IV. What I am looking for is overall performance in frequency domain.

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I downloaded and readed a lot of LTSpice guides, but none of them were speaking about how to do for this kind of circuit. If you know how-to, I would really appriciate yuor help! Maybe it is stupid but I do not know what voltage source (AC, DC, sine or ...) I should use and I do not know which simulation type will be what I need.

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up vote 3 down vote accepted

This tutorial has a good overview of sweeps in LTSpice.

To summarize: Give your voltage source the value AC 1 (where you currently have 1V for a DC source), and the sweep will take care of setting the frequency.

Add a .ac directive, either by using the S shortcut key and typing the Spice directive (The format is .ac [oct|dec|lin] [step size] [start frequency] [stop frequency], where dec/oct/lin refer to a decade, octave, or linear sweep rate) or through the Simulate->Edit Simulation Command menu.

That tutorial also talks about sweeping parameter values to simultaneously plot the response with various capacitor and resistor values with the .param and .step directive. These two tools together are very useful when designing a filter.

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