UCC3813-0: UCC3813-0 Design Calculations

Dhaval Majithia

Part Number: UCC3813-0

I want to use UCC3813-0 in my next design. and want more detailed calculations for my design.

I used the calculations of datasheet (Application Example), but the calculations can't match with my same excel sheet (i.e Lm,Output Capacitance).

Kindly check and suggest

over 7 years ago

0 Peter Meaney over 7 years ago

TI__Mastermind 31580 points

Hi Dhaval,

Can you try attach the excel file again, it does not appear to be attached to your post.

Regards

Peter

0 Dhaval Majithia over 7 years ago in reply to Peter Meaney

Prodigy 30 points

Dear Peter

Thanks. Please find attached excel sheet.

In this Lm and OP Capacitor calculation is there as per application note given in datasheet.

UCC3813-0.xlsx

0 Peter Meaney over 7 years ago in reply to Dhaval Majithia

TI__Mastermind 31580 points

Hi Dhaval,

If you check section 9.2.2.1 you will see that the Vbulk min is 75V and it is not the same as the Vac min. Vbulk min the losest voltage that the bulk cap will drop to close to the zero crossing on the ac line cycle when the power stage is at full load at 85Vac rms line voltage.

If you put 75V into your equations you should be ok.

Regards

Peter

0 Dhaval Majithia over 7 years ago in reply to Peter Meaney

Prodigy 30 points

Hello Peter

Got it.. Thank You.

Power management

Power management forum

UCC3813-0: UCC3813-0 Design Calculations