LM2596: feedforward capacitor selection

Kazuki Kitajima

Part Number: LM2596

Hello team!

I got the question for "cff" from the customer. The datasheet shows Equation6 and uses the 15.4k for R2 for example.

However, the calculated value and the recommended value look different...

Which value should we use for the actual design?

Best Regards,

Kazuki Kitajima

0 Andy Chen over 5 years ago

Hi Kazuki,

I will check and update you later.

B R

Andy

0 Frank De Stasi over 5 years ago in reply to Andy Chen

The equation is mostly an approximation to get a starting value for the CFF.

The values in the table have been tested for best overall performance.

I would plan on using the values in the table.

However, the point of the equation is to ensure that the user leaves a footprint

on the PCB for a feed-forward capacitor if needed. The actual value can be adjusted

to optimize performance in the actual application.

0 Kazuki Kitajima over 5 years ago in reply to Frank De Stasi

Andy-san, Frank-san,

Thank you for your advice!

I'll let the customer know table3 value should be good for.

Best Regards,

Kazuki Kitajima

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