PSR is the original side feedback.
The primary side feedback (PSR) AC\/DC control technology is a new type of AC\/DC control technology developed in the last 10 years. Compared with the traditional optocoupler plus 431 structure with secondary side feedback, its biggest advantage is to eliminate the two chips and a group of components working with them, which saves space on the system board. The cost is reduced and the reliability of the system is improved.