SLUAAQ7A August   2023  – April 2025 UCC256404

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Theory of LLC Topology Design
  6. 3Burst Mode Operating Control Mechanism
  7. 4Potential ZCS Issue When Exiting Burst Mode
  8. 5Design to External Circuit for Solving ZCS Issue at Burst Transition Period
  9. 6Design to Accurate External Circuit for Solving ZCS Issue at Burst Transition Period_(Option)
    1. 6.1 Test Result of External Circuit for Solving ZCS Issue at Burst Transition Period
  10. 7Summary
  11. 8References
  12. 9Revision History

6 Design to Accurate External Circuit for Solving ZCS Issue at Burst Transition Period_(Option)

This is necessary to design the external circuit in more detail for the accurate operation of the auto standby function. We changed the circuit as follows so that the circuit can operate precisely in all AC voltage range conditions (90Vac to 264Vac). The fault signal output circuit was designed as shown in Figure 6-1 to improve the ZCS operation in the burst transition period by changing the small signal FET and shunt regulator configuration to an op amp configuration for more accurate auto standby operation.

Accurate External Auto Standby Circuit With UCC256404Figure 6-1 Accurate External Auto Standby Circuit With UCC256404