Hello and good day,
i was working on my project on led driver using flyback converter. I was using LT1243 as my PWM, when i run my simulation, the expected result for my flyback converter is not shown. I was working on A Design of 9W Closed Loop Flyback Converter with 9.9V, 350mA.

 

The resistor R7 should go to Vref and not to Sense pin??

 

Flyback seems like an odd choice to get from 12V to 9V, buck would be a lot simpler!
You could always delete C1, R2 and D2, and connect a capacitor between the two non-dot ends of the transformer, and then you would have a SEPIC.

 

Post you .asc file.

You circuit has some odd connections as compared to this demo circuit from Analog Devices:

 

Flyback seems like an odd choice to get from 12V to 9V, buck would be a lot simpler!
You could always delete C1, R2 and D2, and connect a capacitor between the two non-dot ends of the transformer, and then you would have a SEPIC.

yes i know for the buck converter, but my supervisor said, i need to work on flyback converter for this project

 

Post you .asc file.

You circuit has some odd connections as compared to this demo circuit from Analog Devices:

View attachment 292365

actually, i try to replicate my benchmark paper, this is their circuit;
this paper works on flyback converter. They Design of 3.3W Closed Loop Flyback Converter
with 3.3V, 1A Output for Low Voltage Applications. As for my project, i tried to design a led driver circuit with a closed loop flyback converter with a 3x1W high power led (white) in series

 

The Rt/Ct pin seems to be connected to the wrong RC components. I think it should be connected to R8 and C4 and the sense pin should be connected to R7 and C3