Microcontroller Integration to Flyback converter

[adnan012]

hi,

i have just finished a 20 watt fly-back converter with wide input range 130 to 700 DC input by following https://www.onsemi.com/pub_link/Collateral/AN1327-D.PDF application note.

Is it possible to add a small micro controller at the output side (which is isolated) to adjust the output voltage by using up down buttons or by using commands through RS232?

 

[treez]

yes you can adjust the output voltage...make the tl431 an opamp error amplifier instead, and feed it a reference voltage (as is normal for error amplifiers of smps)...then just change the reference voltage to suit what output voltage you want....change the ref voltage by eg dac, or digital pot, or switchable resistive divider etc etc....micro can initiate change of ref voltage