circuit and method for controlling circuitry in a power converter device during a soft - start process is provided . synchronous rectifier control circuitry is adapted to gradually apply a gate drive signal derived from the main switch of the power converter device to a freewheeling synchronous rectifier of the switching circuitry during the soft - start process . the control circuitry gradually releases the amplitude or the pulse - width of the gate drive signal to the freewheeling synchronous rectifier to avoid a large duty ratio in the synchronous rectifier during start - up so that a negative current does not build up in the output inductor .