MAX17690
Production
The MAX17690 is a peak current mode, fixed-frequency switching controller specifically designed for the isolated flyback topology operating in Discontinuous...
Datasheet
MAX17690 on Analog.com
The feedback is sampled during the Flyback period (low-side FET off) and is delayed enough to insure that ringing on the primary-side voltage during the initial portion of the Flyback period does not influence the regulated voltage as shown in the diagram below:
