s0lid
Thanks for reply
Please, do not confuse people. Ceramic capacitors - are small brick-type ones, most of them without legs, for mounting on PCB top layer. They hape excellent ESR, ESL and can work with high frequency, like 1-100 MHz range. They are just perfect for filtering and noise removal. But they all have small capacitor, most large (and expensive!) of them have 22-68uF. That's way too small for high-power apps with 500kHz-1MHz switching range. That's why you can find a lot of "usual" cylindrical caps in cans, with electrolyte. They offer good capacity - to thousands of uF, but with much higher ESR, ESL and worse temperature stability. Also can caps usually working good for low frequency, below MHz's, it's like to push huge tank to move. Once you get it moving, it's hard to stop. More frequency > more parasitic heating > less stable... So to lower ESR vendors install a lot of caps in parallel.
Little note: A lot of people saw "digital" VRMs, with only ceramic caps. That's because Volterra (vendor who invented this power units) use high frequency (1-2MHz) for switching, and thus their VRM can work without need of big capacitance for storing charge. Faster frequency - less component size, with same power rating. Remember old bulky 50/60Hz transformers for house mains? They are huge, even with power output only tens of watts. That's because of 50Hz. Increase clock to 5000Hz - and you get 100 times less space and weight for same power. But when you go with extreme overclock - low capacity makes thing bad, and advanced people, like Hipro5 always add solid polymer electrolyte caps to help VRM powering high-power load.
Ceramic caps are perfect for fast transients, big can caps are good for low speed filtering and energy storage. But when you use both - you get pros from each type, and lowering "bad capabilities" of can caps alone a bit.
I'm looking forward for your X48 VRM conversion
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