LTspicePowerSim

2:1 resonant switched-capacitor ladder — fixed phase

LTspicePowerSim's resonant 2:1 ladder, its two switch pairs held at the phase its loop settles to.

Press Run: the example simulates in your browser. Open and simulate takes it to the full app, where you can change it.

Try this

Widen the phase between the pairs to 72° and watch the output rise to 6.7 V. Then press Run again.