Particular embodiments generally relate to detecting an operating mode of a flyback converter. In one embodiment, a voltage of a flyback converter is measured. A waveform for the voltage includes a first rate of change when the flyback converter is in a first mode of operation and a second rate of change when the flyback converter is in a second mode of operation. The presence of the first rate of change or the second rate of change is detected based on the waveform. The first mode of operation or the second mode of operation is determined depending on whether the first rate of change or the second rate of change is detected.