This entry is part 1 of 5 in the series Analog modelling of a diode clipper

I’ve published a few years ago an emulation of the SD1 pedal, but haven’t touched analog modeling since. There are lots of different methods to model a circuit, and they all have different advantages and drawbacks. So I’ve decided to start from scratch again, using two different diode clippers, from the continuous equations to different numerical solutions in a series of blog posts here.

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This entry is part 3a of 5 in the series Analog modelling of a diode clipper

Now that we have a few methods, let’s try to simulate them. For both circuits, I’ll use the forward Euler, then backward Euler and trapezoidal approximations, then I will show the results of changing the start estimate and then finish by the Newton Raphson optimization. I haven’t checked (yet?) algorithms that don’t use the derivative like the bisection or Brent algorithm.

All graphs are done with a x4 oversampling (although I also tried x8, x16 and x32).

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This entry is part 4 of 5 in the series Analog modelling of a diode clipper

Update: It seems I have misunderstood the DK method, so instead I’m using a variation of the Nodal Analysis, so this can be understood as a state-space MNA method.

When analyzing a circuit form scratch, we need to replace all capacitors by an equivalent circuit and solve the equation with this modified circuit. Then, the equivalent currents need to be updated with the proper formula.

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