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I have generated flyback convertor schematic by TI's Webench Power Designer. Parameters: universal AC input (85-265V AC) 5V, 2A output isolated UC3843A controller Basically I understand f...
#2: Post edited
- I have generated flyback convertor schematic by TI's [Webench Power Designer](https://webench.ti.com/power-designer/switching-regulator).
- Parameters:
- - universal AC input (85-265V AC)
- - 5V, 2A output
- - isolated
- - UC3843A controller
- Basically I understand flyback topology, but I do not understand the function of some components around voltage reference (LMV431 used there).
What are R21, C21, D21 for?What are R22, C22, C23 for?- Just cut-out of the schematic:
- 
- Full schematic:
- 
- I have generated flyback convertor schematic by TI's [Webench Power Designer](https://webench.ti.com/power-designer/switching-regulator).
- Parameters:
- - universal AC input (85-265V AC)
- - 5V, 2A output
- - isolated
- - UC3843A controller
- Basically I understand flyback topology, but I do not understand the function of some components around voltage reference (LMV431 used there).
- What are R21, C21, D21 for? How to calculate values?
- What are R22, C22, C23 for? How to calculate values?
- Just cut-out of the schematic:
- 
- Full schematic:
- 
#1: Initial revision
Meaning of some components around voltage reference in SMPS
I have generated flyback convertor schematic by TI's [Webench Power Designer](https://webench.ti.com/power-designer/switching-regulator). Parameters: - universal AC input (85-265V AC) - 5V, 2A output - isolated - UC3843A controller Basically I understand flyback topology, but I do not understand the function of some components around voltage reference (LMV431 used there). What are R21, C21, D21 for? What are R22, C22, C23 for? Just cut-out of the schematic:  Full schematic: 