AnsweredAssumed Answered

Vybrid Power Sequencing wrt USBx_VBUS

Question asked by dougplymale on Apr 19, 2013
Latest reply on Apr 23, 2013 by Naoum Gitnik

Please reference Vybrid Data Sheet, Rev 4.1, 12/2012 chapter 8.1 Power sequencing, Table 26 Power sequencing (Pg. 28 & 29).


I have a couple of questions about this table and notes:

1)  How is "All supplies grouped together e.g. 1, 2, others.  These have no power sequencing restriction in between them." interperted:

     a)  The individuals of the groups do not have power up/down restrictions in reference to the other members of the same group.

     b)  The groups do not have power up/down restrictions between members of other groups

     c)  Other?


2)  In the tower reference design, the USBx_VBUS can be powered outside of the restrictions based on table 26, i.e anytime powered up/down as device bus-powered.  (5V is applied to the device which uses U11 to make the 3.3V.  However 5V is available and up before the 3.3V.)   Is the Data Sheet correct with respect to the sequencing of the 5V USB power?