Buck：D = Vout/Vin，L = (Vin−Vout)·D / (ΔIL·f)。Cout ≈ ΔIL / (8·f·ΔVout)
Boost：D = 1−Vin/Vout，L = Vin·D / (ΔIL·f)。Cout ≈ Iout·D / (f·ΔVout)
默认采用 ΔIL = 纹波系数 × (Buck: Iout；Boost: Iin)。ΔVout/ΔVin 默认 1%V。