7.3.3 Adaptive Blanking Time

In power converters, the sensed the voltage across the SR is often noisy, caused by the parasitic ringing. This parasitic ringing is often associated with the SR and the primary-side switch turning on and off. Blanking time is used to deal with the parasitic ringing to prevent SR false turn on and off. Figure 19 shows more realistic waveforms and the internal control timing which accommodates them.

Figure 19. Parasitic Ringing Associated with DCM Operation