data/text/DLP3/898296

LM2596: feedforward capacitor selection

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

Hi Kazuki, I will check and update you later. B R Andy

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.

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