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How do i build a type 2 compensator for a buck converter in ltspice?

I'm designing a 12V to 3.3V, 15A buck converter and need a Type 2 compensator. How do I implement this in LTspice and tune it properly?

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By Rohan Answered 3 months ago

Use a voltage-mode Type 2 error amplifier with an op-amp, two resistors, and two capacitors. The transfer function is: Gc(s) = (1 + s×R2×C1) / [s×R1×(C1+C2)×(1 + s×R2×(C1×C2/(C1+C2)))]. In LTspice, build this network around an op-amp (like TL081) with R1 from the output to inverting input, and the R2-C1-C2 network in feedback. Target a crossover frequency of 10-30 kHz and phase margin of 45-60°. Sweep R2, C1, C2 to hit those numbers while watching the bode plot.

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