A method for operating an electronic switch in a power converter and a control circuit for operating an electronic switch in a power converter are disclosed. The method includes: driving an electronic switch coupled to an inductor in a power converter in successive drive cycles each including an on-time and an off-time, wherein the off-time includes a demagnetization time period in which the inductor is demagnetized and a delay time, and wherein an end of the delay time is dependent on the occurrence of a predefined number of signal pulses of a pulse signal. The pulse signal includes a first portion that represents local minima of a voltage across the switch and, a second portion that includes signal pulses obtained by timely extrapolating the pulse signal of the first portion.