16 port Passive hub 12v option

[jnealand]

I'm trying to understand why I would need the capacitors and regulator when using an external 12v supply with this hub.  The 4 port passive hub does not have them, just a 12v connection.  Since I understand that you could feed 12v out from the connection to power a 4 port passive hub, my guess is that those parts would be needed if you were using a PC power supply and trying to feed 12v OUT from the connection as opposed to just getting 12v IN.  I'm not an electronics guru so I am having to guess and thought it best to ask.

[rmp2917]

The chips on the hub require 5v or 3.3v power. If you are connecting the hub to a PC power supply through the 24 pin connector, it supplies 5v and 3.3v directly to the board from the power supply. If you use a 12v external supply, you need the regulator and capacitors to provide 5v and 3.3v to the chips.

The 4 port hub does not have any chips and simply passes 12v and data straight to the SSC. So, 5v and 3.3v are not needed.

[jnealand]

Thanks