XRSn pin on the F28002x device is an open drain type driver(Bi-directional), so we need to connect both it and the SP809 to a external PU that will allow either to drive/release the signal. When you remove R108 you are seeing the internal POR/BOR logic control reset exclusively, If SP809 is connected directly to the XRSn pin w/o external PU then there there will be excess current sink to our device, which may be impacting the power up. We use a 2.2kOhm PU on our reference designs, this should work here as well. Also, we need to make sure the boot pins GPIO24 and GPIO32 are properly driven during boot up, which includes some time after XRSn is released(the boot ROM will sample the values on these pins to determine the boot mode). Best, Matthew
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