R_BLEED is used to discharge the clamp capacitor voltage to a residual voltage (V_RESIDUAL) during the 1.5-s fault delay recovery time (t_FDR). After the converter recovers from the fault mode, lower V_RESIDUAL reduces the maximum current stress (I_SHORT(MAX)) flowing through the switching devices within their respective safe operating areas, even if the output voltage is shorted. V_RESIDUAL can be determined by the target I_SHORT(MAX) multiplied with the characteristic impedance between the leakage inductance (L_K) and the clamp capacitor (C_CLAMP). I_SHORT(MAX) is based on the de-rated maximum pulse current of Q_H or the output-rectifier current reflected to the primary side, whichever is lower. This design guide can be applied to both primary and secondary resonance ACF converters. An excessively low value of R_BLEED results in over-discharging of C_CLAMP, and introduces excess continuous power loss which affects standby power.

Equation 40.

Equation 41.