POP Assumptions:

  1. That the circuit is initialized close to steady state:
    • Inductor currents are close to steady-state values
    • Capacitor voltages are close to steady-state values
    • Logic and Switches are in the correct states
  2. PWL sources are held at their t=0 values for the POP analysis!
  3. Large signal, non-repeating sources are also held at their t=0 values!
  4. That there is no low frequency perturbation to the circuit, e.g. soft-start.

References

How POP Really Works