Hi all, electronic theory question ahead,
Quick background - I'm repairing a SMPS in an Dick Smith LCD TV. It looks like the MOSFET had failed dramatically so I replaced all the affected components. It still wont switch so I now suspect the PWM controller got a taste of 240v where it shouldn't have.
While diagnosing the IC I pulled up the datasheet and found the attached diagram and had a question. With reference to the application circuit in the datasheet, how is it that the VDD voltage is generated since there is no switching on the transformer?
The IC is a OB5269, datasheet attached.
![SMPS theroy question 976474-0](https://www.eevblog.com/forum/index.php?action=dlattach;topic=239002.0;attach=976476;image)
Regards,
GoBo