While reviewing the reference design for TPS562201 in WebBENCH I noticed that three GRM188R60J226MEA0 ceramic 22uF 6.3v caps were used in parallel to achieve ~24uF after derating, and a much lower total BOM cost compared to a single 35v or 50v 22uF cap. Creative!
Does this approach to reduce the total BOM cost have a negative impact on the life of the capacitors? In elevated temperatures of ~50C?
Thank you to Arthur of the MEA Tech Help Desk who pointed me to the link below from MuRata for accelerated life testing. The short answer is that yes, it does reduce the life... though it may be outside the limits of what some designers are concerned about. A small increase of rated voltage compared to applied voltage has a very large impact to increasing life. The same is true for increasing the temperature rating as well.
