A design guide for the PR6850C isolated AC-DC switch power supply chip, covering features, working principles, and transformer design calculations.
This document serves as a design guide for the PR6850C, an integrated chip used in isolated AC-DC switch power supplies. It highlights key features such as low startup current (approx 8µA), current mode control with built-in synchronous slope compensation, and adjustable PWM frequency. The guide supports applications including AC/DC adapters, battery chargers, and set-top box power supplies.
The document recommends setting the reflected voltage between 60V and 80V to ensure the maximum duty cycle does not exceed 0.5.
The guide suggests setting the auxiliary winding voltage greater than 11.5V to prevent false triggering of UVLO during load transitions.