Once again looking at a ceramic capacitor specification sheet and being reminded of how horrific DC bias de-rating can be. This 22uF capacitor turns into a 4.75uF capacitor at 24V DC: https://ds.yuden.co.jp/TYCOMPAS/or/detail?pn=MSASG32MSB5226MPNA01&u=M
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@jpm Yeah, you can basically assume -80% at anything over ~half the voltage rating, and -20% at any useful DC bias at all.
@jaseg this part in particular is Quite Good Actually at my output target 3.3V, only -2% or so.
@jpm yeah but it's kinda ridiculous that you have to know to overspec a part like that in voltage by a factor of 10. A 35V part is also larger and has worse parasitics compared to a 4V spec'ed one.
@jaseg oh this happened to be via BOM optimisation - I selected it as the input capacitor for up to 30V, and happened to be quite good as the output capacitor so kept it for both duties.
