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Question Regarding Page 4 of F28069 Controller Card Schematic

Other Parts Discussed in Thread: TMS320F28069

Hello,

I have a design with the TMS320F28069 - and am using the Control Card as a reference - (ISO version) - 

I have a question regarding page 4 of the attached schematic - 0363.F2806XISO-CONTROLCARDR0.3-SCH.pdf

If the 5V0 source is generated from the Control Card Docking Station - and the USB MICRO AB is plugged in  - 
and U200 is 'ON' - (D200 will be on if VBUS > +5V + Vf D200) - doesn't this cause a short of the USB VBUS voltage
and +5V?  

I have one of these boards - so I can do some testing on my own - but I wanted to ask how this is supposed to work - I can imagine the algorithm is something like this:  (I haven't reviewed the firmware) -

Voltage on VBUS_DET?
If yes - do not enable USB_ENA, if no - enable U200.

Is there a requirement on the '069's USB Bus to always have a VBUS voltage present once the USB module is enabled?

Thanks!
johnw