UCC2803: Flyback isolated AC/DC converter

ABHISHEK KUMAR

Part Number: UCC2803

Hii Everyone,

I have designed a 19 V, 60 W ac-dc converter using UCC2803 on tina ti took help from Webench, but it is giving convergence error. Attaching the simulation file and Webench circuit screenshot. Please suggest.

Thank you!!

UCC2803.TSC

over 3 years ago

0 Jerry Xu over 3 years ago

TI__Expert 3160 points

Select Analysis-Transient-Use initial conditions. Then you can run the simulation successfully.

0 ABHISHEK KUMAR over 3 years ago in reply to Jerry Xu

Prodigy 120 points

yeah, it is running, but not getting the required output voltage. Also, it takes more time to observe signals at the comp and other pins.

0 Jerry Xu over 3 years ago in reply to ABHISHEK KUMAR

TI__Expert 3160 points

Could you upload the updated simulation? I run your original simulation mode. The output voltage VF1 is normal.

0 ABHISHEK KUMAR over 3 years ago in reply to Jerry Xu

Prodigy 120 points

Hii Jerry:

I haven't updated anything but still not getting proper output voltage.

Thanks

3582.UCC2803.TSC

0 Jerry Xu over 3 years ago in reply to ABHISHEK KUMAR

TI__Expert 3160 points

Analysis-Set Analysis parameters. You can change the parameters and try again.

0 ABHISHEK KUMAR over 3 years ago in reply to Jerry Xu

Prodigy 120 points

Hii Jerry!!!

Which parameters exactly?? Can you please suggest?

Thanks

0 ABHISHEK KUMAR over 3 years ago in reply to ABHISHEK KUMAR

Prodigy 120 points

Hii Jerry!!!

Waiting for your reply!!!

Thanks

0 Jerry Xu over 3 years ago in reply to ABHISHEK KUMAR

TI__Expert 3160 points

Your system is very complicated, I don’t know the specific parameters. You can try to change the TR max.iteration number, TR maximum value relative error.

0 Jerry Xu over 3 years ago in reply to ABHISHEK KUMAR

TI__Expert 3160 points

10.1-10.7 is China's National Day. I will be back on 10.8.

+1 Jerry Xu over 3 years ago

TI__Expert 3160 points

Hi, ABHISHEK

I reviewed the simulation model. The driver have some problems. When the out of UCC2803 is high. The main switch cannot conduct. You can test the Vds waveform of main switch. The Vds is always equal to Vin.

0 ABHISHEK KUMAR over 3 years ago in reply to Jerry Xu

Prodigy 120 points

Thanks..the problem is already solved.

0 ABHISHEK KUMAR over 3 years ago in reply to ABHISHEK KUMAR

Prodigy 120 points

Hii

Can you tell me what is use of both the bipolar transistor used in the circuit??

Thanks

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UCC2803: Flyback isolated AC/DC converter