Universal AC Input 5V/2A USB Adaptor with PSR Reference Design
This reference design provides an isolated 5V/2A output from a universal 85-265VAC input. This design uses the UCC28710 PWM controller with primary-side regulation (PSR) eliminating the need for an optocoupler and saving cost. Maximum load efficiency is over 82%. The UCC28710 also provides accurate current limiting which eliminates the need for a load protecting switch on the output.