RC-Snubber Calculation

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I used formulas from On-Semiconductor here.
For calculation of the RC-snubber of a Flyback-Regulator.

L_stray[H]

V_clamp[V]

V_ripple[V]

F_switch[Hz]

I_p[A]

N[1]

V_o+V_f[V]

R[Ohm]

C[F]

Explanation:

L_stray: stray inductivity
V_clamp: desired clamp voltage. This adds to the DC rail. Ripple not included!
V_ripple: allowable ripple in V. Note: This adds to V_clamp!
F_switch: clock frequency of the regulator in Hz
I_p: maximum current through the switch in A
N: winding ratio of the transformer (dimensionless)
V_o+V_f: output voltage plus diode drop in V

The capacitor should be bigger than the calculated value (the bigger, the lower the ripple voltage) the resistor smaller (the smaller, the lower V_clamp)