Supply Current clarification

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I am using this IC (https://ww1.microchip.com/downloads...Sheets/USB251xB-xBi-Data-Sheet-DS00001692.pdf ) and this IC ( https://www.nve.com/Downloads/il5xx.pdf )

For the USB Hub IC, I will be using one upstream port and 2 downstream ports. In that case, what should be my supply current?

I found in the table 6-4, page 41 of the USB datasheet, since both the downstream ports will be High speed, it mentioned 85mA per downstream port, but also mentions the below marked:



I am not able to understand what does 1 port base +25mA mean? And why and when I should include in my calculation?

I thought since I am using 2 downstream ports, my supply current would be 2*85mA = 170mA. Am I correct or missing something? And I am planning to use 480Mbps high speed.

And for the isolator part, the total supply current is mention as input supply currents on page 8 which are less than 10mA values? Can I take those values for both VDD1 and VDD2 supply inputs? Can someone clarify?
 

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