In this example, a simplified design procedure will be discussed. The compensation network for the feedback network is beyond the scope of this section. Details on compensation network can be found in Compensation Design with TL431 for UCC28600 Application Report.
The goal of this design is to design a low standby current feedback network to meet the Europe CoC Tier 2 and United States DoE Level VI requirements. To meet the design requirements, the system standby power needs to be below 75 mW. To meet this, the feedback network needs to consume less than 40 mW to allow margin for the power losses on the primary side controller and passive components. This can pose a challenge in systems greater than 10 V.