Description
The MAXREFDES1227 is a miniature 12V output isolated power supply that can deliver up to 2A load current. The design employs the MAX17596 peak-current-mode controller in discontinuous-conduction mode (DCM) flyback topology running at 125kHz. The input voltage range of MAX17596 is 4.5V to 36V; however, an extra bias winding from the transformer is used to power the controller. This allows an input operating voltage of up to 60V for this design.The transformer provides a galvanic isolation of 1500VRMS between the primary and the secondary. In addition, an optocoupler is used to provide secondary side feedback to the controller for voltage regulation while maintaining isolation. This document also discusses a step-by-step procedure that is used to implement this reference design. Design equations for the calculation of all the design parameters are presented. These equations show how the component values were calculated enabling users to modify this design for their applications.