UCC28950: Input power calculation

Shweta Sapate

Part Number: UCC28950

I am designing a DC-DC converter using UCC28950.For Input power calculation ,I am taking average of Input current using average tool. When I am changing the time interval , average value also get changes. How to get accurate value?

over 3 years ago

0 Mike O' over 3 years ago

TI__Guru* 81146 points

Hello,

When you change the duty cycle your average input current will change. Iave = Ipeak*Ton/Tp = Ipeak*D.

Also make sure you include efficiency as well. Pin = Pout/efficiency Iin = Vin/Pout

Regards,

0 Shweta Sapate over 3 years ago in reply to Mike O'

Prodigy 50 points

Hello Mike,

For same duty ratio when I am zooming the waveform ,average is changing, You can see that on above image.

Mike O' said:
Iave = Ipeak*Ton/Tp = Ipeak*D.

D=Dtypical value??

Mike O' said:
Iin = Vin/Pout

It would be Pin??

0 Mike O' over 3 years ago in reply to Shweta Sapate

TI__Guru* 81146 points

Hello,

It should not be for a given load. You loop might be unstable. You might want to check to make sure you have enough phase and gain margin.

Regards,

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UCC28950: Input power calculation